Case Letter

To the Editor:

Pseudoxanthoma elasticum (PXE) is a genetic perforating dermatosis characterized by fragmentation and calcification of elastic fibers that most commonly manifests on the skin, eyes, gastrointestinal tract, or cardiovascular system.¹ Classic skin findings include multiple symmetric yellowish papules favoring the flexural surfaces of the body and neck as well as the periumbilical and inguinal regions.^1,2 Many life-threatening complications from this disease can occur due to calcification of elastic fibers in other parts of the body, such as the internal elastic lamina of arteries, which can cause gastrointestinal tract bleeding and accelerated cardiovascular disease including valvular disease.^2,3 If PXE is localized to the skin only without systemic involvement or a family history, a diagnosis of perforating calcific elastosis (PCE) can be made. We report a case of PCE in a patient with a growing umbilical lesion.

A 49-year-old multiparous (gravida 3, para 3) woman presented for evaluation of an evolving periumbilical lesion of 4 months’ duration. She denied pain, bleeding, or drainage from the area, as well as any systemic symptoms. The patient had a surgical history of a laparoscopic hysterectomy 7 years prior to the current presentation due to uterine fibroids, which resulted in a periumbilical scar. At the current presentation, physical examination revealed 2 hyperpigmented to violaceous periumbilical papules coalescing into a plaque with overlying hyperkeratosis and crusting (Figure 1). A punch biopsy was performed and histopathology showed diffuse dermal collections of degenerated eosinophilic distorted elastic fibers with calcification (Figure 2). Further sections showed a transepidermal channel in which the elastic fibers extruded from the dermis through the epidermis (Figure 3). The diagnosis of acquired PCE was made based on the clinical presentation, relevant medical history, and lack of underlying medical conditions or family history of PXE. No further workup was needed, and the patient reported no further progression and rather some improvement (decrease in size) of the lesion at 3-month follow-up.

Perforating calcific elastosis (also known as periumbilical perforating PXE) is a rare acquired condition that is seen predominantly in multiparous middle-aged women.^4-6 This diagnosis consists of degenerated calcified elastic fibers that may perforate the skin of the abdominal or periumbilical region. It clinically manifests as multiple painless hyperkeratotic papules surrounding the periumbilical region.^4-6

The etiology and pathogenesis of PCE have not been defined but have been attributed to recurrent stressing of elastic fibers due to repeat traumas,¹ which is proposed to lead to degeneration of elastic fibers and calcification of damaged tissue.^4-7 As a result, PCE most commonly manifests in multiparous, obese, middle-aged women and patients with multiple abdominal surgeries or ascites.¹ It also has been reported in patients with renal failure due to deposition of abnormal calcium phosphate products onto elastic fibers.⁴ In our patient, the development of PCE was related to both multiparity and trauma from prior surgery.

The histopathologic findings of PCE and PXE are similar, warranting differentiation via thorough clinical examination as well as further investigation of the patient’s medical and family history. Both show degenerated, fragmented, curly elastic fibers with calcium deposition throughout the dermis and a transepidermal channel extruding these elastic fibers.^7,8 The biopsies stain positive for elastic fibers and calcium deposition. Calcium staining can help to differentiate these entities from elastosis perforans serpiginosa, which lacks the presence of calcium staining.⁷

There are no definitive treatments for PCE. A single case report of a patient with PCE and renal failure showed regression with hemodialysis.⁹ In a study evaluating patients with inherited PXE, notable improvement was seen in skin lesions treated with bisphosphonates, possibly suggesting that regulating serum calcium may contribute to improvement of the disease.³ Most cases spontaneously resolve with atrophic plaques. Our patient required no additional treatment with no further progression and reported improvement of the lesion with spontaneous decrease in size.

To the Editor:

Pseudoxanthoma elasticum (PXE) is a genetic perforating dermatosis characterized by fragmentation and calcification of elastic fibers that most commonly manifests on the skin, eyes, gastrointestinal tract, or cardiovascular system.¹ Classic skin findings include multiple symmetric yellowish papules favoring the flexural surfaces of the body and neck as well as the periumbilical and inguinal regions.^1,2 Many life-threatening complications from this disease can occur due to calcification of elastic fibers in other parts of the body, such as the internal elastic lamina of arteries, which can cause gastrointestinal tract bleeding and accelerated cardiovascular disease including valvular disease.^2,3 If PXE is localized to the skin only without systemic involvement or a family history, a diagnosis of perforating calcific elastosis (PCE) can be made. We report a case of PCE in a patient with a growing umbilical lesion.

A 49-year-old multiparous (gravida 3, para 3) woman presented for evaluation of an evolving periumbilical lesion of 4 months’ duration. She denied pain, bleeding, or drainage from the area, as well as any systemic symptoms. The patient had a surgical history of a laparoscopic hysterectomy 7 years prior to the current presentation due to uterine fibroids, which resulted in a periumbilical scar. At the current presentation, physical examination revealed 2 hyperpigmented to violaceous periumbilical papules coalescing into a plaque with overlying hyperkeratosis and crusting (Figure 1). A punch biopsy was performed and histopathology showed diffuse dermal collections of degenerated eosinophilic distorted elastic fibers with calcification (Figure 2). Further sections showed a transepidermal channel in which the elastic fibers extruded from the dermis through the epidermis (Figure 3). The diagnosis of acquired PCE was made based on the clinical presentation, relevant medical history, and lack of underlying medical conditions or family history of PXE. No further workup was needed, and the patient reported no further progression and rather some improvement (decrease in size) of the lesion at 3-month follow-up.

Perforating calcific elastosis (also known as periumbilical perforating PXE) is a rare acquired condition that is seen predominantly in multiparous middle-aged women.^4-6 This diagnosis consists of degenerated calcified elastic fibers that may perforate the skin of the abdominal or periumbilical region. It clinically manifests as multiple painless hyperkeratotic papules surrounding the periumbilical region.^4-6

The etiology and pathogenesis of PCE have not been defined but have been attributed to recurrent stressing of elastic fibers due to repeat traumas,¹ which is proposed to lead to degeneration of elastic fibers and calcification of damaged tissue.^4-7 As a result, PCE most commonly manifests in multiparous, obese, middle-aged women and patients with multiple abdominal surgeries or ascites.¹ It also has been reported in patients with renal failure due to deposition of abnormal calcium phosphate products onto elastic fibers.⁴ In our patient, the development of PCE was related to both multiparity and trauma from prior surgery.

The histopathologic findings of PCE and PXE are similar, warranting differentiation via thorough clinical examination as well as further investigation of the patient’s medical and family history. Both show degenerated, fragmented, curly elastic fibers with calcium deposition throughout the dermis and a transepidermal channel extruding these elastic fibers.^7,8 The biopsies stain positive for elastic fibers and calcium deposition. Calcium staining can help to differentiate these entities from elastosis perforans serpiginosa, which lacks the presence of calcium staining.⁷

There are no definitive treatments for PCE. A single case report of a patient with PCE and renal failure showed regression with hemodialysis.⁹ In a study evaluating patients with inherited PXE, notable improvement was seen in skin lesions treated with bisphosphonates, possibly suggesting that regulating serum calcium may contribute to improvement of the disease.³ Most cases spontaneously resolve with atrophic plaques. Our patient required no additional treatment with no further progression and reported improvement of the lesion with spontaneous decrease in size.

To the Editor:

Pseudoxanthoma elasticum (PXE) is a genetic perforating dermatosis characterized by fragmentation and calcification of elastic fibers that most commonly manifests on the skin, eyes, gastrointestinal tract, or cardiovascular system.¹ Classic skin findings include multiple symmetric yellowish papules favoring the flexural surfaces of the body and neck as well as the periumbilical and inguinal regions.^1,2 Many life-threatening complications from this disease can occur due to calcification of elastic fibers in other parts of the body, such as the internal elastic lamina of arteries, which can cause gastrointestinal tract bleeding and accelerated cardiovascular disease including valvular disease.^2,3 If PXE is localized to the skin only without systemic involvement or a family history, a diagnosis of perforating calcific elastosis (PCE) can be made. We report a case of PCE in a patient with a growing umbilical lesion.

A 49-year-old multiparous (gravida 3, para 3) woman presented for evaluation of an evolving periumbilical lesion of 4 months’ duration. She denied pain, bleeding, or drainage from the area, as well as any systemic symptoms. The patient had a surgical history of a laparoscopic hysterectomy 7 years prior to the current presentation due to uterine fibroids, which resulted in a periumbilical scar. At the current presentation, physical examination revealed 2 hyperpigmented to violaceous periumbilical papules coalescing into a plaque with overlying hyperkeratosis and crusting (Figure 1). A punch biopsy was performed and histopathology showed diffuse dermal collections of degenerated eosinophilic distorted elastic fibers with calcification (Figure 2). Further sections showed a transepidermal channel in which the elastic fibers extruded from the dermis through the epidermis (Figure 3). The diagnosis of acquired PCE was made based on the clinical presentation, relevant medical history, and lack of underlying medical conditions or family history of PXE. No further workup was needed, and the patient reported no further progression and rather some improvement (decrease in size) of the lesion at 3-month follow-up.

Perforating calcific elastosis (also known as periumbilical perforating PXE) is a rare acquired condition that is seen predominantly in multiparous middle-aged women.^4-6 This diagnosis consists of degenerated calcified elastic fibers that may perforate the skin of the abdominal or periumbilical region. It clinically manifests as multiple painless hyperkeratotic papules surrounding the periumbilical region.^4-6

The etiology and pathogenesis of PCE have not been defined but have been attributed to recurrent stressing of elastic fibers due to repeat traumas,¹ which is proposed to lead to degeneration of elastic fibers and calcification of damaged tissue.^4-7 As a result, PCE most commonly manifests in multiparous, obese, middle-aged women and patients with multiple abdominal surgeries or ascites.¹ It also has been reported in patients with renal failure due to deposition of abnormal calcium phosphate products onto elastic fibers.⁴ In our patient, the development of PCE was related to both multiparity and trauma from prior surgery.

The histopathologic findings of PCE and PXE are similar, warranting differentiation via thorough clinical examination as well as further investigation of the patient’s medical and family history. Both show degenerated, fragmented, curly elastic fibers with calcium deposition throughout the dermis and a transepidermal channel extruding these elastic fibers.^7,8 The biopsies stain positive for elastic fibers and calcium deposition. Calcium staining can help to differentiate these entities from elastosis perforans serpiginosa, which lacks the presence of calcium staining.⁷

There are no definitive treatments for PCE. A single case report of a patient with PCE and renal failure showed regression with hemodialysis.⁹ In a study evaluating patients with inherited PXE, notable improvement was seen in skin lesions treated with bisphosphonates, possibly suggesting that regulating serum calcium may contribute to improvement of the disease.³ Most cases spontaneously resolve with atrophic plaques. Our patient required no additional treatment with no further progression and reported improvement of the lesion with spontaneous decrease in size.

To the Editor:

Lyme disease is caused by spirochetes of the Borrelia burgdorferi sensu lato species complex and transmitted to humans by the bite of the Ixodes scapularis tick. It was first classified as a nationally notifiable disease in 1991, and the incidence has risen remarkably since then.¹ More than 63,000 cases are reported annually to the Centers for Disease Control and Prevention; however, this number reflects severe underreporting, as the true incidence of the disease is projected to be closer to 476,000 cases per year.² Additionally, 95% of US cases occur in the Northeast and upper Midwest.³ Given the pervasiveness of Lyme disease, early and reliable diagnostic methodology is critical, especially in cases in which the timeline of inoculation is unclear. We present a case of Lyme disease that was discovered during a routine dermatologic visit.

A 77-year-old White man with no relevant medical history presented to a dermatology clinic in west-central Virginia for a routine skin check. Physical examination revealed a well-appearing patient without overt skin abnormalities. However, on closer evaluation, a ­0.2×0.1-cm engorged black I scapularis tick was visualized on the left lateral upper back. There was a surrounding zone of erythema that measured less than the 5-cm-diameter criterion for erythema migrans.¹

Upon questioning, the patient reported that he was unaware of the tick and could not provide a timeline for inoculation. To ensure proper treatment, the tick was removed in the office and a specimen was sent for histopathology. The arthropod was formalin fixed and paraffin embedded, and it was examined using hematoxylin and eosin and Warthin-Starry stains. Histopathology of the specimen revealed a blood-engorged arthropod. Warthin-Starry stain of the abdomen of the tick highlighted tiny strandlike spirochetes within the gut that were compatible with B burgdorferi (Figure). This finding prompted treatment with a 3-week course of doxycycline. Following treatment, erythema resolved. The patient experienced no sequelae.

Lyme disease can cause a range of serious complications if left untreated, including arthritis, neurologic deficits, and heart block. During the early stages of disease, the sensitivity and specificity of diagnostic methods such as serologic testing are limited.⁴ The gold standard for the diagnosis of Lyme disease comprises culture and subsequent confirmation by polymerase chain reaction.¹ However, cultivation of B burgdorferi is challenging.⁵ The Centers for Disease Control and Prevention recommends 2-tiered serologic antibody analysis, which has 27% sensitivity during the first week of cutaneous symptoms, and involves an enzyme-linked immunoassay followed by reflexive immunoblotting for positive or indeterminate cases.^2,6 The precision of this method is limited by several variables; for example, seroconversion fails to occur in approximately 40% of cases, even after proven exposure to the spirochete.⁷ Furthermore, the sensitivity of the test is particularly low during the first 4 to 6 weeks of infection—before the body mounts a proper immune response; fewer than 50% of patients exhibit a positive response to the test at initial presentation.³

Clinical diagnosis of Lyme disease is possible, though the pathognomonic erythema migrans rash can be delayed for as long as 30 days and remains absent in 20% to 30% of patients.¹ Prophylactic treatment can be offered to individuals who reside in a hyperendemic area and have a rash or have had an engorged Ixodes tick attached for longer than 36 hours.⁸

More definitive techniques for early diagnosis are needed to enable selective and accurate treatment. The standard of care for Lyme disease includes a 10-day course of doxycycline or a 14-day course of cefuroxime axetil or amoxicillin.⁹ Many patients tolerate treatment and achieve resolution of disease, but antibiotics are not benign, as some patients experience drug-related adverse effects such as photosensitivity, urticaria, diarrhea, nausea, vomiting, esophagitis, hepatotoxicity, and the Jarisch-Herxheimer reaction (fever, chills, rigors, nausea and vomiting, headache, tachycardia, hypotension, hyperventilation, flushing, myalgia, and exacerbation of lesions).^10,11 In a group of 123 patients with Lyme disease, 30% treated with cefuroxime axetil and 32% treated with doxycycline had 1 or more drug-related adverse events.¹⁰ Additionally, avoidable antibiotic use is associated with increasing antibiotic resistance.¹² Improved diagnostic accuracy would prevent unnecessary treatment. Galan and colleagues⁷ reported that Warthin-Starry staining of prepared sections of the abdomen of a tick allowed for detection of B burgdorferi with a sensitivity of 71% and specificity of 83%. This technique did not delay the final biopsy report and may be a promising adjunct to the diagnosis of early Lyme disease.⁷

Anecdotally, many patients who present with an attached and engorged tick are unaware of the timeline of their exposure. Histologic analysis of a removed tick could aid in early clinical decision-making—ie, when the diagnosis is unclear and treatment guidelines vary by region and circumstance. Improved sensitivity and specificity of diagnosis can prevent unnecessary antibiotic treatment, which is associated with adverse effects and escalation of antibiotic resistance.

To the Editor:

Lyme disease is caused by spirochetes of the Borrelia burgdorferi sensu lato species complex and transmitted to humans by the bite of the Ixodes scapularis tick. It was first classified as a nationally notifiable disease in 1991, and the incidence has risen remarkably since then.¹ More than 63,000 cases are reported annually to the Centers for Disease Control and Prevention; however, this number reflects severe underreporting, as the true incidence of the disease is projected to be closer to 476,000 cases per year.² Additionally, 95% of US cases occur in the Northeast and upper Midwest.³ Given the pervasiveness of Lyme disease, early and reliable diagnostic methodology is critical, especially in cases in which the timeline of inoculation is unclear. We present a case of Lyme disease that was discovered during a routine dermatologic visit.

A 77-year-old White man with no relevant medical history presented to a dermatology clinic in west-central Virginia for a routine skin check. Physical examination revealed a well-appearing patient without overt skin abnormalities. However, on closer evaluation, a ­0.2×0.1-cm engorged black I scapularis tick was visualized on the left lateral upper back. There was a surrounding zone of erythema that measured less than the 5-cm-diameter criterion for erythema migrans.¹

Upon questioning, the patient reported that he was unaware of the tick and could not provide a timeline for inoculation. To ensure proper treatment, the tick was removed in the office and a specimen was sent for histopathology. The arthropod was formalin fixed and paraffin embedded, and it was examined using hematoxylin and eosin and Warthin-Starry stains. Histopathology of the specimen revealed a blood-engorged arthropod. Warthin-Starry stain of the abdomen of the tick highlighted tiny strandlike spirochetes within the gut that were compatible with B burgdorferi (Figure). This finding prompted treatment with a 3-week course of doxycycline. Following treatment, erythema resolved. The patient experienced no sequelae.

Lyme disease can cause a range of serious complications if left untreated, including arthritis, neurologic deficits, and heart block. During the early stages of disease, the sensitivity and specificity of diagnostic methods such as serologic testing are limited.⁴ The gold standard for the diagnosis of Lyme disease comprises culture and subsequent confirmation by polymerase chain reaction.¹ However, cultivation of B burgdorferi is challenging.⁵ The Centers for Disease Control and Prevention recommends 2-tiered serologic antibody analysis, which has 27% sensitivity during the first week of cutaneous symptoms, and involves an enzyme-linked immunoassay followed by reflexive immunoblotting for positive or indeterminate cases.^2,6 The precision of this method is limited by several variables; for example, seroconversion fails to occur in approximately 40% of cases, even after proven exposure to the spirochete.⁷ Furthermore, the sensitivity of the test is particularly low during the first 4 to 6 weeks of infection—before the body mounts a proper immune response; fewer than 50% of patients exhibit a positive response to the test at initial presentation.³

Clinical diagnosis of Lyme disease is possible, though the pathognomonic erythema migrans rash can be delayed for as long as 30 days and remains absent in 20% to 30% of patients.¹ Prophylactic treatment can be offered to individuals who reside in a hyperendemic area and have a rash or have had an engorged Ixodes tick attached for longer than 36 hours.⁸

More definitive techniques for early diagnosis are needed to enable selective and accurate treatment. The standard of care for Lyme disease includes a 10-day course of doxycycline or a 14-day course of cefuroxime axetil or amoxicillin.⁹ Many patients tolerate treatment and achieve resolution of disease, but antibiotics are not benign, as some patients experience drug-related adverse effects such as photosensitivity, urticaria, diarrhea, nausea, vomiting, esophagitis, hepatotoxicity, and the Jarisch-Herxheimer reaction (fever, chills, rigors, nausea and vomiting, headache, tachycardia, hypotension, hyperventilation, flushing, myalgia, and exacerbation of lesions).^10,11 In a group of 123 patients with Lyme disease, 30% treated with cefuroxime axetil and 32% treated with doxycycline had 1 or more drug-related adverse events.¹⁰ Additionally, avoidable antibiotic use is associated with increasing antibiotic resistance.¹² Improved diagnostic accuracy would prevent unnecessary treatment. Galan and colleagues⁷ reported that Warthin-Starry staining of prepared sections of the abdomen of a tick allowed for detection of B burgdorferi with a sensitivity of 71% and specificity of 83%. This technique did not delay the final biopsy report and may be a promising adjunct to the diagnosis of early Lyme disease.⁷

Anecdotally, many patients who present with an attached and engorged tick are unaware of the timeline of their exposure. Histologic analysis of a removed tick could aid in early clinical decision-making—ie, when the diagnosis is unclear and treatment guidelines vary by region and circumstance. Improved sensitivity and specificity of diagnosis can prevent unnecessary antibiotic treatment, which is associated with adverse effects and escalation of antibiotic resistance.

To the Editor:

Lyme disease is caused by spirochetes of the Borrelia burgdorferi sensu lato species complex and transmitted to humans by the bite of the Ixodes scapularis tick. It was first classified as a nationally notifiable disease in 1991, and the incidence has risen remarkably since then.¹ More than 63,000 cases are reported annually to the Centers for Disease Control and Prevention; however, this number reflects severe underreporting, as the true incidence of the disease is projected to be closer to 476,000 cases per year.² Additionally, 95% of US cases occur in the Northeast and upper Midwest.³ Given the pervasiveness of Lyme disease, early and reliable diagnostic methodology is critical, especially in cases in which the timeline of inoculation is unclear. We present a case of Lyme disease that was discovered during a routine dermatologic visit.

A 77-year-old White man with no relevant medical history presented to a dermatology clinic in west-central Virginia for a routine skin check. Physical examination revealed a well-appearing patient without overt skin abnormalities. However, on closer evaluation, a ­0.2×0.1-cm engorged black I scapularis tick was visualized on the left lateral upper back. There was a surrounding zone of erythema that measured less than the 5-cm-diameter criterion for erythema migrans.¹

Upon questioning, the patient reported that he was unaware of the tick and could not provide a timeline for inoculation. To ensure proper treatment, the tick was removed in the office and a specimen was sent for histopathology. The arthropod was formalin fixed and paraffin embedded, and it was examined using hematoxylin and eosin and Warthin-Starry stains. Histopathology of the specimen revealed a blood-engorged arthropod. Warthin-Starry stain of the abdomen of the tick highlighted tiny strandlike spirochetes within the gut that were compatible with B burgdorferi (Figure). This finding prompted treatment with a 3-week course of doxycycline. Following treatment, erythema resolved. The patient experienced no sequelae.

Lyme disease can cause a range of serious complications if left untreated, including arthritis, neurologic deficits, and heart block. During the early stages of disease, the sensitivity and specificity of diagnostic methods such as serologic testing are limited.⁴ The gold standard for the diagnosis of Lyme disease comprises culture and subsequent confirmation by polymerase chain reaction.¹ However, cultivation of B burgdorferi is challenging.⁵ The Centers for Disease Control and Prevention recommends 2-tiered serologic antibody analysis, which has 27% sensitivity during the first week of cutaneous symptoms, and involves an enzyme-linked immunoassay followed by reflexive immunoblotting for positive or indeterminate cases.^2,6 The precision of this method is limited by several variables; for example, seroconversion fails to occur in approximately 40% of cases, even after proven exposure to the spirochete.⁷ Furthermore, the sensitivity of the test is particularly low during the first 4 to 6 weeks of infection—before the body mounts a proper immune response; fewer than 50% of patients exhibit a positive response to the test at initial presentation.³

Clinical diagnosis of Lyme disease is possible, though the pathognomonic erythema migrans rash can be delayed for as long as 30 days and remains absent in 20% to 30% of patients.¹ Prophylactic treatment can be offered to individuals who reside in a hyperendemic area and have a rash or have had an engorged Ixodes tick attached for longer than 36 hours.⁸

More definitive techniques for early diagnosis are needed to enable selective and accurate treatment. The standard of care for Lyme disease includes a 10-day course of doxycycline or a 14-day course of cefuroxime axetil or amoxicillin.⁹ Many patients tolerate treatment and achieve resolution of disease, but antibiotics are not benign, as some patients experience drug-related adverse effects such as photosensitivity, urticaria, diarrhea, nausea, vomiting, esophagitis, hepatotoxicity, and the Jarisch-Herxheimer reaction (fever, chills, rigors, nausea and vomiting, headache, tachycardia, hypotension, hyperventilation, flushing, myalgia, and exacerbation of lesions).^10,11 In a group of 123 patients with Lyme disease, 30% treated with cefuroxime axetil and 32% treated with doxycycline had 1 or more drug-related adverse events.¹⁰ Additionally, avoidable antibiotic use is associated with increasing antibiotic resistance.¹² Improved diagnostic accuracy would prevent unnecessary treatment. Galan and colleagues⁷ reported that Warthin-Starry staining of prepared sections of the abdomen of a tick allowed for detection of B burgdorferi with a sensitivity of 71% and specificity of 83%. This technique did not delay the final biopsy report and may be a promising adjunct to the diagnosis of early Lyme disease.⁷

Anecdotally, many patients who present with an attached and engorged tick are unaware of the timeline of their exposure. Histologic analysis of a removed tick could aid in early clinical decision-making—ie, when the diagnosis is unclear and treatment guidelines vary by region and circumstance. Improved sensitivity and specificity of diagnosis can prevent unnecessary antibiotic treatment, which is associated with adverse effects and escalation of antibiotic resistance.

To the Editor:

A 56-year-old man was referred to our Grand Rounds by another dermatologist in our health system for evaluation of a red scaly rash on the trunk that had been present for more than a year. More recently, over the course of approximately 9 months he experienced recurrent painful penile ulcers that lasted for approximately 4 weeks and then self-resolved. He had a medical history of central retinal vein occlusion, primary hyperparathyroidism, and nonspecific colitis. A family history was notable for lung cancer in the patient’s father and myelodysplastic syndrome and breast cancer in his mother; however, there was no family history of a similar rash. A bacterial culture of the penile ulcer was negative. Testing for antibodies against HIV and herpes simplex virus (HSV) types 1 and 2 was negative. Results of a serum VDRL test were nonreactive, which ruled out syphilis. The patient was treated by the referring dermatologist with azithromycin for possible chancroid without relief.

The patient was being followed by the referring dermatologist who initially was concerned for Degos disease based on clinical examination findings, prompting biopsy of a lesion on the back, which revealed vacuolar interface dermatitis, a sparse superficial perivascular lymphocytic infiltrate, and increased mucin—all highly suspicious for connective tissue disease (Figure 1). An antinuclear antibody test was positive, with a titer of 1:640. The patient was started on prednisone and referred to rheumatology; however, further evaluation by rheumatology for an autoimmune process—including anticardiolipin antibodies—was unremarkable. A few months prior to the current presentation, he also had mildly elevated liver function test results. A colonoscopy was performed, and a biopsy revealed nonspecific colitis. A biopsy of the penile ulcer also was nonspecific, showing only ulceration and acute and chronic inflammation. No epidermal interface change was seen. Results from a Grocott-Gomori methenamine-silver stain, Treponema pallidum immunostain, and HSV polymerase chain reaction were negative for fungal organisms, spirochetes, and HSV, respectively. The differential diagnosis included trauma, aphthous ulceration, and Behçet disease. Behçet disease was suspected by the referring dermatologist, and the patient was treated with colchicine, prednisone, pimecrolimus cream, and topical lidocaine; however, the lesions persisted, and he was subsequently referred to our Grand Rounds for further evaluation.

At the current presentation, physical examination revealed several small papules with white atrophic centers and erythematous rims on the trunk and extremities (Figure 2A). An ulceration was noted on the penile shaft (Figure 2B). Further evaluation for Behçet disease, including testing for pathergy and HLA-B51, was negative. Degos disease was strongly suspected clinically, and a repeat biopsy was performed of a lesion on the abdomen, which revealed central epidermal necrosis, atrophy, and parakeratosis with an underlying wedge-shaped dermal infarct surrounded by multiple small occluded dermal vessels, perivascular inflammation, and dermal edema (Figure 3). Direct immunofluorescence was performed using antibodies against IgG, IgA, IgM, fibrinogen, albumin, and C3, which was negative. These findings from direct immunofluorescence and histopathology as well as the clinical presentation were considered compatible with Degos disease. The patient was started on aspirin and pentoxifylline. Pentoxifylline 400 mg twice daily appeared to lessen some of the pain. Pain management specialists started the patient on gabapentin.

Approximately 4 months after the Grand Rounds evaluation, during which time he continued treatment with pentoxifylline, he was admitted to the hospital for intractable nausea and vomiting. His condition acutely declined due to bowel perforation, and he was started on eculizumab 1200 mg every 14 days. Because of an increased risk for meningococcal meningitis while on this medication, he also was given erythromycin 500 mg twice daily prophylactically. He was being followed by hematology for the vasculopathy, and they were planning to monitor for any disease changes with computed tomography of the chest, abdomen, and pelvis every 3 months, as well as echocardiogram every 6 months for any development of pericardial or pleural fibrosis. Approximately 1 month later, the patient was admitted to the hospital again but died after 1 week from gastrointestinal complications (approximately 22 months after the onset of the rash).

Degos disease (atrophic papulosis) is a rare small vessel vasculopathy of unknown etiology, but complement-mediated endothelial injury plays a role.^1,2 It typically occurs in the fourth decade of life, with a slight female predominance.^3,4 The skin lesions are characteristic and described as 5- to 10-mm papules with atrophic white centers and erythematous telangiectatic rims, most commonly on the upper body and typically sparing the head, palms, and soles.¹ Penile ulceration is an uncommon cutaneous feature, with only a few cases reported in the literature.^5,6 Approximately one-third of patients will have only skin lesions, but two-thirds will develop systemic involvement 1 to 2 years after onset, with the gastrointestinal tract and central nervous system most commonly involved. For those with systemic involvement, the 5-year survival rate is approximately 55%, and the most common causes of death are bowel perforation, peritonitis, and stroke.^3,4 Because some patients appear to never develop systemic complications, Theodoridis et al⁴ proposed that the disease be classified as either malignant atrophic papulosis or benign atrophic papulosis to indicate the malignant systemic form and the benign cutaneous form, respectively.

The histopathology of Degos disease changes as the lesions evolve.⁷ Early lesions show a superficial and deep perivascular and periadnexal lymphocytic infiltrate, possible interface dermatitis, and dermal mucin resembling lupus. The more fully developed lesions show a greater degree of inflammation and interface change as well as lymphocytic vasculitis. This stage also may have epidermal atrophy and early papillary dermal sclerosis resembling lichen sclerosus. The late-stage lesions, clinically observed as papules with atrophic white centers and surrounding erythema, show the classic pathology of wedge-shaped dermal sclerosis and central epidermal atrophy with surrounding hyperkeratosis. Interface dermatitis and dermal mucin can be seen in all stages, though mucin is diminished in the later stage.

Effective treatment options are limited; however, antithrombotics or compounds that facilitate blood perfusion, such as aspirin or pentoxifylline, initially can be used.¹ Eculizumab, a humanized monoclonal antibody that prevents the cleavage of C5, has been used for salvage therapy,⁸ as in our case. Treprostinil, a prostacyclin analog that causes arterial vasodilation and inhibition of platelet aggregation, has been reported to improve bowel and cutaneous lesions, functional status, and neurologic symptoms.⁹

Our case highlights important features of Degos disease. First, it is important for both the clinician and the pathologist to recognize that the histopathology of Degos disease changes as the lesions evolve. In our case, although the lesions were characteristic of Degos disease clinically, the initial biopsy was suspicious for connective tissue disease, which led to an autoimmune evaluation that ultimately was unremarkable. Recognizing that early lesions of Degos disease can resemble connective tissue disease histologically could have prevented this delay in diagnosis. However, Degos disease has been reported in association with autoimmune diseases.¹⁰ Second, although penile ulceration is uncommon, it can be a prominent cutaneous manifestation of the disease. Finally, eculizumab and treprostinil are therapeutic options that have shown some efficacy in improving symptoms and cutaneous lesions.^8,9

To the Editor:

A 56-year-old man was referred to our Grand Rounds by another dermatologist in our health system for evaluation of a red scaly rash on the trunk that had been present for more than a year. More recently, over the course of approximately 9 months he experienced recurrent painful penile ulcers that lasted for approximately 4 weeks and then self-resolved. He had a medical history of central retinal vein occlusion, primary hyperparathyroidism, and nonspecific colitis. A family history was notable for lung cancer in the patient’s father and myelodysplastic syndrome and breast cancer in his mother; however, there was no family history of a similar rash. A bacterial culture of the penile ulcer was negative. Testing for antibodies against HIV and herpes simplex virus (HSV) types 1 and 2 was negative. Results of a serum VDRL test were nonreactive, which ruled out syphilis. The patient was treated by the referring dermatologist with azithromycin for possible chancroid without relief.

The patient was being followed by the referring dermatologist who initially was concerned for Degos disease based on clinical examination findings, prompting biopsy of a lesion on the back, which revealed vacuolar interface dermatitis, a sparse superficial perivascular lymphocytic infiltrate, and increased mucin—all highly suspicious for connective tissue disease (Figure 1). An antinuclear antibody test was positive, with a titer of 1:640. The patient was started on prednisone and referred to rheumatology; however, further evaluation by rheumatology for an autoimmune process—including anticardiolipin antibodies—was unremarkable. A few months prior to the current presentation, he also had mildly elevated liver function test results. A colonoscopy was performed, and a biopsy revealed nonspecific colitis. A biopsy of the penile ulcer also was nonspecific, showing only ulceration and acute and chronic inflammation. No epidermal interface change was seen. Results from a Grocott-Gomori methenamine-silver stain, Treponema pallidum immunostain, and HSV polymerase chain reaction were negative for fungal organisms, spirochetes, and HSV, respectively. The differential diagnosis included trauma, aphthous ulceration, and Behçet disease. Behçet disease was suspected by the referring dermatologist, and the patient was treated with colchicine, prednisone, pimecrolimus cream, and topical lidocaine; however, the lesions persisted, and he was subsequently referred to our Grand Rounds for further evaluation.

At the current presentation, physical examination revealed several small papules with white atrophic centers and erythematous rims on the trunk and extremities (Figure 2A). An ulceration was noted on the penile shaft (Figure 2B). Further evaluation for Behçet disease, including testing for pathergy and HLA-B51, was negative. Degos disease was strongly suspected clinically, and a repeat biopsy was performed of a lesion on the abdomen, which revealed central epidermal necrosis, atrophy, and parakeratosis with an underlying wedge-shaped dermal infarct surrounded by multiple small occluded dermal vessels, perivascular inflammation, and dermal edema (Figure 3). Direct immunofluorescence was performed using antibodies against IgG, IgA, IgM, fibrinogen, albumin, and C3, which was negative. These findings from direct immunofluorescence and histopathology as well as the clinical presentation were considered compatible with Degos disease. The patient was started on aspirin and pentoxifylline. Pentoxifylline 400 mg twice daily appeared to lessen some of the pain. Pain management specialists started the patient on gabapentin.

Approximately 4 months after the Grand Rounds evaluation, during which time he continued treatment with pentoxifylline, he was admitted to the hospital for intractable nausea and vomiting. His condition acutely declined due to bowel perforation, and he was started on eculizumab 1200 mg every 14 days. Because of an increased risk for meningococcal meningitis while on this medication, he also was given erythromycin 500 mg twice daily prophylactically. He was being followed by hematology for the vasculopathy, and they were planning to monitor for any disease changes with computed tomography of the chest, abdomen, and pelvis every 3 months, as well as echocardiogram every 6 months for any development of pericardial or pleural fibrosis. Approximately 1 month later, the patient was admitted to the hospital again but died after 1 week from gastrointestinal complications (approximately 22 months after the onset of the rash).

Degos disease (atrophic papulosis) is a rare small vessel vasculopathy of unknown etiology, but complement-mediated endothelial injury plays a role.^1,2 It typically occurs in the fourth decade of life, with a slight female predominance.^3,4 The skin lesions are characteristic and described as 5- to 10-mm papules with atrophic white centers and erythematous telangiectatic rims, most commonly on the upper body and typically sparing the head, palms, and soles.¹ Penile ulceration is an uncommon cutaneous feature, with only a few cases reported in the literature.^5,6 Approximately one-third of patients will have only skin lesions, but two-thirds will develop systemic involvement 1 to 2 years after onset, with the gastrointestinal tract and central nervous system most commonly involved. For those with systemic involvement, the 5-year survival rate is approximately 55%, and the most common causes of death are bowel perforation, peritonitis, and stroke.^3,4 Because some patients appear to never develop systemic complications, Theodoridis et al⁴ proposed that the disease be classified as either malignant atrophic papulosis or benign atrophic papulosis to indicate the malignant systemic form and the benign cutaneous form, respectively.

The histopathology of Degos disease changes as the lesions evolve.⁷ Early lesions show a superficial and deep perivascular and periadnexal lymphocytic infiltrate, possible interface dermatitis, and dermal mucin resembling lupus. The more fully developed lesions show a greater degree of inflammation and interface change as well as lymphocytic vasculitis. This stage also may have epidermal atrophy and early papillary dermal sclerosis resembling lichen sclerosus. The late-stage lesions, clinically observed as papules with atrophic white centers and surrounding erythema, show the classic pathology of wedge-shaped dermal sclerosis and central epidermal atrophy with surrounding hyperkeratosis. Interface dermatitis and dermal mucin can be seen in all stages, though mucin is diminished in the later stage.

Effective treatment options are limited; however, antithrombotics or compounds that facilitate blood perfusion, such as aspirin or pentoxifylline, initially can be used.¹ Eculizumab, a humanized monoclonal antibody that prevents the cleavage of C5, has been used for salvage therapy,⁸ as in our case. Treprostinil, a prostacyclin analog that causes arterial vasodilation and inhibition of platelet aggregation, has been reported to improve bowel and cutaneous lesions, functional status, and neurologic symptoms.⁹

Our case highlights important features of Degos disease. First, it is important for both the clinician and the pathologist to recognize that the histopathology of Degos disease changes as the lesions evolve. In our case, although the lesions were characteristic of Degos disease clinically, the initial biopsy was suspicious for connective tissue disease, which led to an autoimmune evaluation that ultimately was unremarkable. Recognizing that early lesions of Degos disease can resemble connective tissue disease histologically could have prevented this delay in diagnosis. However, Degos disease has been reported in association with autoimmune diseases.¹⁰ Second, although penile ulceration is uncommon, it can be a prominent cutaneous manifestation of the disease. Finally, eculizumab and treprostinil are therapeutic options that have shown some efficacy in improving symptoms and cutaneous lesions.^8,9

To the Editor:

A 56-year-old man was referred to our Grand Rounds by another dermatologist in our health system for evaluation of a red scaly rash on the trunk that had been present for more than a year. More recently, over the course of approximately 9 months he experienced recurrent painful penile ulcers that lasted for approximately 4 weeks and then self-resolved. He had a medical history of central retinal vein occlusion, primary hyperparathyroidism, and nonspecific colitis. A family history was notable for lung cancer in the patient’s father and myelodysplastic syndrome and breast cancer in his mother; however, there was no family history of a similar rash. A bacterial culture of the penile ulcer was negative. Testing for antibodies against HIV and herpes simplex virus (HSV) types 1 and 2 was negative. Results of a serum VDRL test were nonreactive, which ruled out syphilis. The patient was treated by the referring dermatologist with azithromycin for possible chancroid without relief.

The patient was being followed by the referring dermatologist who initially was concerned for Degos disease based on clinical examination findings, prompting biopsy of a lesion on the back, which revealed vacuolar interface dermatitis, a sparse superficial perivascular lymphocytic infiltrate, and increased mucin—all highly suspicious for connective tissue disease (Figure 1). An antinuclear antibody test was positive, with a titer of 1:640. The patient was started on prednisone and referred to rheumatology; however, further evaluation by rheumatology for an autoimmune process—including anticardiolipin antibodies—was unremarkable. A few months prior to the current presentation, he also had mildly elevated liver function test results. A colonoscopy was performed, and a biopsy revealed nonspecific colitis. A biopsy of the penile ulcer also was nonspecific, showing only ulceration and acute and chronic inflammation. No epidermal interface change was seen. Results from a Grocott-Gomori methenamine-silver stain, Treponema pallidum immunostain, and HSV polymerase chain reaction were negative for fungal organisms, spirochetes, and HSV, respectively. The differential diagnosis included trauma, aphthous ulceration, and Behçet disease. Behçet disease was suspected by the referring dermatologist, and the patient was treated with colchicine, prednisone, pimecrolimus cream, and topical lidocaine; however, the lesions persisted, and he was subsequently referred to our Grand Rounds for further evaluation.

At the current presentation, physical examination revealed several small papules with white atrophic centers and erythematous rims on the trunk and extremities (Figure 2A). An ulceration was noted on the penile shaft (Figure 2B). Further evaluation for Behçet disease, including testing for pathergy and HLA-B51, was negative. Degos disease was strongly suspected clinically, and a repeat biopsy was performed of a lesion on the abdomen, which revealed central epidermal necrosis, atrophy, and parakeratosis with an underlying wedge-shaped dermal infarct surrounded by multiple small occluded dermal vessels, perivascular inflammation, and dermal edema (Figure 3). Direct immunofluorescence was performed using antibodies against IgG, IgA, IgM, fibrinogen, albumin, and C3, which was negative. These findings from direct immunofluorescence and histopathology as well as the clinical presentation were considered compatible with Degos disease. The patient was started on aspirin and pentoxifylline. Pentoxifylline 400 mg twice daily appeared to lessen some of the pain. Pain management specialists started the patient on gabapentin.

Approximately 4 months after the Grand Rounds evaluation, during which time he continued treatment with pentoxifylline, he was admitted to the hospital for intractable nausea and vomiting. His condition acutely declined due to bowel perforation, and he was started on eculizumab 1200 mg every 14 days. Because of an increased risk for meningococcal meningitis while on this medication, he also was given erythromycin 500 mg twice daily prophylactically. He was being followed by hematology for the vasculopathy, and they were planning to monitor for any disease changes with computed tomography of the chest, abdomen, and pelvis every 3 months, as well as echocardiogram every 6 months for any development of pericardial or pleural fibrosis. Approximately 1 month later, the patient was admitted to the hospital again but died after 1 week from gastrointestinal complications (approximately 22 months after the onset of the rash).

Degos disease (atrophic papulosis) is a rare small vessel vasculopathy of unknown etiology, but complement-mediated endothelial injury plays a role.^1,2 It typically occurs in the fourth decade of life, with a slight female predominance.^3,4 The skin lesions are characteristic and described as 5- to 10-mm papules with atrophic white centers and erythematous telangiectatic rims, most commonly on the upper body and typically sparing the head, palms, and soles.¹ Penile ulceration is an uncommon cutaneous feature, with only a few cases reported in the literature.^5,6 Approximately one-third of patients will have only skin lesions, but two-thirds will develop systemic involvement 1 to 2 years after onset, with the gastrointestinal tract and central nervous system most commonly involved. For those with systemic involvement, the 5-year survival rate is approximately 55%, and the most common causes of death are bowel perforation, peritonitis, and stroke.^3,4 Because some patients appear to never develop systemic complications, Theodoridis et al⁴ proposed that the disease be classified as either malignant atrophic papulosis or benign atrophic papulosis to indicate the malignant systemic form and the benign cutaneous form, respectively.

The histopathology of Degos disease changes as the lesions evolve.⁷ Early lesions show a superficial and deep perivascular and periadnexal lymphocytic infiltrate, possible interface dermatitis, and dermal mucin resembling lupus. The more fully developed lesions show a greater degree of inflammation and interface change as well as lymphocytic vasculitis. This stage also may have epidermal atrophy and early papillary dermal sclerosis resembling lichen sclerosus. The late-stage lesions, clinically observed as papules with atrophic white centers and surrounding erythema, show the classic pathology of wedge-shaped dermal sclerosis and central epidermal atrophy with surrounding hyperkeratosis. Interface dermatitis and dermal mucin can be seen in all stages, though mucin is diminished in the later stage.

Effective treatment options are limited; however, antithrombotics or compounds that facilitate blood perfusion, such as aspirin or pentoxifylline, initially can be used.¹ Eculizumab, a humanized monoclonal antibody that prevents the cleavage of C5, has been used for salvage therapy,⁸ as in our case. Treprostinil, a prostacyclin analog that causes arterial vasodilation and inhibition of platelet aggregation, has been reported to improve bowel and cutaneous lesions, functional status, and neurologic symptoms.⁹

Our case highlights important features of Degos disease. First, it is important for both the clinician and the pathologist to recognize that the histopathology of Degos disease changes as the lesions evolve. In our case, although the lesions were characteristic of Degos disease clinically, the initial biopsy was suspicious for connective tissue disease, which led to an autoimmune evaluation that ultimately was unremarkable. Recognizing that early lesions of Degos disease can resemble connective tissue disease histologically could have prevented this delay in diagnosis. However, Degos disease has been reported in association with autoimmune diseases.¹⁰ Second, although penile ulceration is uncommon, it can be a prominent cutaneous manifestation of the disease. Finally, eculizumab and treprostinil are therapeutic options that have shown some efficacy in improving symptoms and cutaneous lesions.^8,9

To the Editor:

A 32-year-old man presented to our clinic with acute-onset erythroderma associated with severe itching of 1 month’s duration. The patient developed the eruption after receiving the second dose of the Sinopharm BBIBP COVID-19 vaccine (BBIBP-CorV) 2 weeks prior to presentation. His medical history was unremarkable. There was no personal or family history of skin disease and no history of drug intake. Physical examination revealed orange-red erythroderma (Figure 1A) with islands of sparing,keratotic follicular orange-red papules on both legs and feet (Figure 1B), well-defined waxy palmoplantar keratoderma (Figures 1C and 1D), and fine scales on the face and scalp. The clinical and laboratory workup were normal, including a negative test for HIV infection.

Histopathology of two 4-mm punch biopsies of the skin on the trunk and lower limb showed irregular epidermal hyperplasia with thick suprapapillary plates and hypergranulosis (Figure 2A) along with alternating orthokeratosis and parakeratosis in vertical and horizontal directions (checkerboard parakeratosis)(Figure 2B). Follicular plugging with shoulder parakeratosis also was seen. The dermis showed a mild, superficial, perivascular lymphohistiocytic infiltrate. These features were diagnostic of pityriasis rubra pilaris (PRP). The patient received acitretin 25 mg/d and methotrexate 17.5 mg/wk (0.4 mg/kg/wk) and showed marked improvement after 2 months of therapy.

Pityriasis rubra pilaris is a rare papulosquamous skin disease of unknown etiology with several theories including genetic factors, aberrant metabolism of vitamin A, infection, drug reaction, autoimmune disease, and malignancy.¹ Clinically, there are 6 types of PRP: type I (classical adult), type II (atypical adult), type III (classical juvenile), type IV (circumscribed juvenile), type V (atypical juvenile), and type VI (HIV associated). Classic features include orange-red keratotic follicular papules that coalesce into plaques with characteristic islands of sparing.¹

Pityriasis rubra pilaris is a rare sequela following administration of certain vaccines, including diphtheria, pertussis, and tetanus; measles-mumps-rubella; and polio vaccines.^2,3 Among the various skin reactions that have been reported following COVID-19 vaccination, PRP has been reported in 19 patients: 7 (36.8%) after AstraZeneca vaccination, 3 (15.8%) after CoronaVac, 3 (15.8%) after Moderna, 5 (26.3%) after Pfizer-BioNTech,⁴ and 1 (5.3%) after Sinopharm.⁵ Our patient represents an additional case of a reaction after the Sinopharm vaccine. The condition developed after the first dose of vaccine in 11 patients, after the second dose in 6 patients, and after the third dose in 2 patients.

Other papulosquamous skin reactions have been reported after the Sinopharm BBIBP-CorV vaccine including psoriasis, lichen planus, and pityriasis rosea. Skin manifestations occurred sporadically, as some happened after the first or second dose or even after booster doses. The exact pathogenic mechanism(s) underlying the development of these conditions following vaccination still are not understood, though they may be attributed to COVID-19 vaccine–induced immune dysregulation.⁶

Pityriasis rubra pilaris can be self-limited in some cases and may not require treatment. Topical therapies such as keratolytics, emollients, and vitamin D may be utilized, especially for localized disease. Systemic therapy may be needed for refractory cases, including retinoids or immunosuppressive medications such as methotrexate, which is considered a second-line treatment for refractory PRP (after retinoids) and was used in our case. Azathioprine and cyclosporine also may be used. Phototherapy may play a role in PRP treatment, but the response is variable.⁷

Pityriasis rubra pilaris should be added to the list of cutaneous adverse reactions that can occur following vaccination with the Sinopharm BBIBP-CorV vaccine. Dermatologists must be aware of the possibility of vaccine-induced PRP, especially in de novo cases.

To the Editor:

A 32-year-old man presented to our clinic with acute-onset erythroderma associated with severe itching of 1 month’s duration. The patient developed the eruption after receiving the second dose of the Sinopharm BBIBP COVID-19 vaccine (BBIBP-CorV) 2 weeks prior to presentation. His medical history was unremarkable. There was no personal or family history of skin disease and no history of drug intake. Physical examination revealed orange-red erythroderma (Figure 1A) with islands of sparing,keratotic follicular orange-red papules on both legs and feet (Figure 1B), well-defined waxy palmoplantar keratoderma (Figures 1C and 1D), and fine scales on the face and scalp. The clinical and laboratory workup were normal, including a negative test for HIV infection.

Histopathology of two 4-mm punch biopsies of the skin on the trunk and lower limb showed irregular epidermal hyperplasia with thick suprapapillary plates and hypergranulosis (Figure 2A) along with alternating orthokeratosis and parakeratosis in vertical and horizontal directions (checkerboard parakeratosis)(Figure 2B). Follicular plugging with shoulder parakeratosis also was seen. The dermis showed a mild, superficial, perivascular lymphohistiocytic infiltrate. These features were diagnostic of pityriasis rubra pilaris (PRP). The patient received acitretin 25 mg/d and methotrexate 17.5 mg/wk (0.4 mg/kg/wk) and showed marked improvement after 2 months of therapy.

Pityriasis rubra pilaris is a rare papulosquamous skin disease of unknown etiology with several theories including genetic factors, aberrant metabolism of vitamin A, infection, drug reaction, autoimmune disease, and malignancy.¹ Clinically, there are 6 types of PRP: type I (classical adult), type II (atypical adult), type III (classical juvenile), type IV (circumscribed juvenile), type V (atypical juvenile), and type VI (HIV associated). Classic features include orange-red keratotic follicular papules that coalesce into plaques with characteristic islands of sparing.¹

Pityriasis rubra pilaris is a rare sequela following administration of certain vaccines, including diphtheria, pertussis, and tetanus; measles-mumps-rubella; and polio vaccines.^2,3 Among the various skin reactions that have been reported following COVID-19 vaccination, PRP has been reported in 19 patients: 7 (36.8%) after AstraZeneca vaccination, 3 (15.8%) after CoronaVac, 3 (15.8%) after Moderna, 5 (26.3%) after Pfizer-BioNTech,⁴ and 1 (5.3%) after Sinopharm.⁵ Our patient represents an additional case of a reaction after the Sinopharm vaccine. The condition developed after the first dose of vaccine in 11 patients, after the second dose in 6 patients, and after the third dose in 2 patients.

Other papulosquamous skin reactions have been reported after the Sinopharm BBIBP-CorV vaccine including psoriasis, lichen planus, and pityriasis rosea. Skin manifestations occurred sporadically, as some happened after the first or second dose or even after booster doses. The exact pathogenic mechanism(s) underlying the development of these conditions following vaccination still are not understood, though they may be attributed to COVID-19 vaccine–induced immune dysregulation.⁶

Pityriasis rubra pilaris can be self-limited in some cases and may not require treatment. Topical therapies such as keratolytics, emollients, and vitamin D may be utilized, especially for localized disease. Systemic therapy may be needed for refractory cases, including retinoids or immunosuppressive medications such as methotrexate, which is considered a second-line treatment for refractory PRP (after retinoids) and was used in our case. Azathioprine and cyclosporine also may be used. Phototherapy may play a role in PRP treatment, but the response is variable.⁷

Pityriasis rubra pilaris should be added to the list of cutaneous adverse reactions that can occur following vaccination with the Sinopharm BBIBP-CorV vaccine. Dermatologists must be aware of the possibility of vaccine-induced PRP, especially in de novo cases.

To the Editor:

A 32-year-old man presented to our clinic with acute-onset erythroderma associated with severe itching of 1 month’s duration. The patient developed the eruption after receiving the second dose of the Sinopharm BBIBP COVID-19 vaccine (BBIBP-CorV) 2 weeks prior to presentation. His medical history was unremarkable. There was no personal or family history of skin disease and no history of drug intake. Physical examination revealed orange-red erythroderma (Figure 1A) with islands of sparing,keratotic follicular orange-red papules on both legs and feet (Figure 1B), well-defined waxy palmoplantar keratoderma (Figures 1C and 1D), and fine scales on the face and scalp. The clinical and laboratory workup were normal, including a negative test for HIV infection.

Histopathology of two 4-mm punch biopsies of the skin on the trunk and lower limb showed irregular epidermal hyperplasia with thick suprapapillary plates and hypergranulosis (Figure 2A) along with alternating orthokeratosis and parakeratosis in vertical and horizontal directions (checkerboard parakeratosis)(Figure 2B). Follicular plugging with shoulder parakeratosis also was seen. The dermis showed a mild, superficial, perivascular lymphohistiocytic infiltrate. These features were diagnostic of pityriasis rubra pilaris (PRP). The patient received acitretin 25 mg/d and methotrexate 17.5 mg/wk (0.4 mg/kg/wk) and showed marked improvement after 2 months of therapy.

Pityriasis rubra pilaris is a rare papulosquamous skin disease of unknown etiology with several theories including genetic factors, aberrant metabolism of vitamin A, infection, drug reaction, autoimmune disease, and malignancy.¹ Clinically, there are 6 types of PRP: type I (classical adult), type II (atypical adult), type III (classical juvenile), type IV (circumscribed juvenile), type V (atypical juvenile), and type VI (HIV associated). Classic features include orange-red keratotic follicular papules that coalesce into plaques with characteristic islands of sparing.¹

Pityriasis rubra pilaris is a rare sequela following administration of certain vaccines, including diphtheria, pertussis, and tetanus; measles-mumps-rubella; and polio vaccines.^2,3 Among the various skin reactions that have been reported following COVID-19 vaccination, PRP has been reported in 19 patients: 7 (36.8%) after AstraZeneca vaccination, 3 (15.8%) after CoronaVac, 3 (15.8%) after Moderna, 5 (26.3%) after Pfizer-BioNTech,⁴ and 1 (5.3%) after Sinopharm.⁵ Our patient represents an additional case of a reaction after the Sinopharm vaccine. The condition developed after the first dose of vaccine in 11 patients, after the second dose in 6 patients, and after the third dose in 2 patients.

Other papulosquamous skin reactions have been reported after the Sinopharm BBIBP-CorV vaccine including psoriasis, lichen planus, and pityriasis rosea. Skin manifestations occurred sporadically, as some happened after the first or second dose or even after booster doses. The exact pathogenic mechanism(s) underlying the development of these conditions following vaccination still are not understood, though they may be attributed to COVID-19 vaccine–induced immune dysregulation.⁶

Pityriasis rubra pilaris can be self-limited in some cases and may not require treatment. Topical therapies such as keratolytics, emollients, and vitamin D may be utilized, especially for localized disease. Systemic therapy may be needed for refractory cases, including retinoids or immunosuppressive medications such as methotrexate, which is considered a second-line treatment for refractory PRP (after retinoids) and was used in our case. Azathioprine and cyclosporine also may be used. Phototherapy may play a role in PRP treatment, but the response is variable.⁷

Pityriasis rubra pilaris should be added to the list of cutaneous adverse reactions that can occur following vaccination with the Sinopharm BBIBP-CorV vaccine. Dermatologists must be aware of the possibility of vaccine-induced PRP, especially in de novo cases.

To the Editor:

Sporotrichosis refers to a subacute to chronic fungal infection that usually involves the cutaneous and subcutaneous tissues and is caused by the introduction of Sporothrix, a dimorphic fungus, through the skin. We present a case of chronic atypical lymphocutaneous sporotrichosis.

A 46-year-old man presented to the outpatient dermatology clinic for follow-up for a rash on the right leg that spread to the thigh and became painful and pruritic. It initially developed 8 years prior to the current presentation after he sustained trauma to the leg from an electroshock weapon. One year prior to the current presentation, he had presented to the emergency department and was prescribed doxycycline 100 mg twice daily for 7 days as well as bacitracin ointment. He also was instructed to follow up with dermatology, but a lack of health insurance and other socioeconomic barriers prevented him from seeking dermatologic care. Nine months later, he again presented to the emergency department due to a motor vehicle accident. Computed tomography (CT) of the right leg revealed exophytic dermal masses, inflammatory stranding of the subcutaneous tissue, and right inguinal lymph nodes measuring up to 1.4 cm; there was no osteoarticular involvement. At that time, the patient was applying gentian violet to the skin lesions and taking hydroxyzine 50 mg 3 times daily as needed for pruritus with minimal relief. Financial support was provided for follow-up with dermatology, which occurred almost 5 months later.

At the current presentation, physical examination revealed a large annular plaque with verrucous, scaly, erythematous borders and a hypopigmented atrophic center extending from the medial aspect of the right leg to the posterior thigh. Numerous pink, scaly, crusted nodules were scattered primarily along the periphery, with some evidence of draining sinus tracts. In addition, a fibrotic pink linear plaque extended from the medial right leg to the popliteal fossa, consistent with a keloid. Violet staining along the periphery of the lesion also was appreciated secondary to the application of topical gentian violet (Figure 1).

Based on the chronic history and morphology, a diagnosis of a chronic fungal or atypical mycobacterial infection was favored. In particular, chromoblastomycosis, cutaneous tuberculosis (eg, scrofuloderma, lupus vulgaris, tuberculosis verrucosa cutis), and atypical mycobacterial infection were highest on the differential, as these conditions often exhibit annular, nodular, verrucous, and/or atrophic lesions. The nodularity, crusting, and draining sinus tracts also raised the possibility of mycetoma. Given the extension of the lesion from the lower to upper leg, a sporotrichoid infection also was considered but was thought to be less likely based on the annular configuration.

Two 4-mm punch biopsies were taken from a peripheral nodule—one for routine histology and another for bacterial, fungal, and mycobacterial cultures. An ­interferon-gamma release assay also was ordered to evaluate for immune responses indicative of prior Mycobacterium tuberculosis infection, but the patient did not obtain this for unknown reasons. Histology demonstrated pseudoepitheliomatous hyperplasia and necrotizing granulomas, which suggested an infectious etiology, but no organisms were identified on tissue staining and all cultures were negative for growth at 6 weeks. The patient was asked to return at that point, and 4 additional scouting biopsies were performed and sent for routine histology, M tuberculosis nucleic acid amplification testing, and microbiologic cultures (ie, bacterial, mycobacterial, fungal, nocardia, actinomycetes). Within 1 week, a filamentous organism with pigmentation visible on the front and back of a Sabouraud dextrose agar plate was identified on fungal culture (Figure 2). Microscopic evaluation of this mold with lactophenol blue stain revealed thin septate hyphae with conidiophores arising at right angles that bore clusters of microconidia (Figure 3). Sequencing analysis ultimately identified this organism as Sporothrix schenckii. Routine histology demonstrated pseudoepitheliomatous hyperplasia with scattered intraepidermal collections of neutrophils (Figure 4). The dermis showed a dense, superficial, and deep infiltrate composed of lymphocytes, histiocytes, and plasma cells with occasional neutrophils and eosinophils. A Grocott-Gomori methenamine-silver stain revealed a cluster of ovoid yeast forms within the stratum corneum (Figure 5). The patient was referred to infectious disease for follow-up and treatment.

The patient later visited a community clinic providing dermatologic care for patients without insurance. He was started on itraconazole 200 mg daily for a total of 6 months until dermatologic clearance of the cutaneous lesions was observed. He was followed by the clinic with laboratory tests including a liver function test. At follow-up 8 months later, a repeat biopsy was performed to ensure histologic clearance of the sporotrichosis, which revealed a dermal scar and no evidence of residual infection.

Sporothrix schenckii was first isolated in 1898 by Benjamin Schenck, a student at Johns Hopkins Medicine (Baltimore, Maryland), and identified by a mycologist as sporotricha.¹ Species within the genus Sporothrix are unique in that the fungi are both dimorphic (growing as a mold at 25 °C but as a yeast at 37 °C) and dematiaceous (dark pigmentation from melanin is visible on inspection of the anterior and reverse sides of culture plates). Infection usually occurs when cutaneous or subcutaneous tissues are exposed to the fungus via microabrasions; activities thought to contribute to exposure include gardening, agricultural work, animal husbandry, and feline scratches.² Although skin trauma frequently is considered the primary route of infection, patient recall is variable, with one study noting that only 37.7% of patients recalled trauma and another study similarly demonstrating a patient recall rate of 25%.^3,4

Lymphocutaneous sporotrichosis is the most common presentation of the fungal infection,⁵ and clinical cases may be classified into 1 of 4 categories: (1) lymphangitic lesions—papules at the site of inoculation with spread along the lymphatic channels; (2) localized (fixed) cutaneous lesions—1 or 2 lesions at the inoculation site; (3) disseminated (multifocal) cutaneous lesions; and (4) extracutaneous lesions.⁶ Extracutaneous manifestations of this infection most notably have been reported as pulmonary disease through inhalation of conidia or through dissemination in immunocompromised hosts.⁷ Our patient’s infection was categorized as lymphangitic lesions due to spread from the lower to upper leg, albeit in a highly atypical, annular fashion. A review of systems was otherwise negative, and CT ruled out osteoarticular involvement.

In addition to socioeconomic barriers, several factors contributed to a delayed diagnosis in this patient including the annular presentation with central hypopigmentation and atrophy, negative initial microbiological cultures and lack of visualization of organisms on histopathology, and the consequent need for repeat biopsies. For lymphocutaneous sporotrichosis, the typical presentation consists of a papule or ulcerated nodule at the site of inoculation with subsequent linear spread along lymphatic channels. This classic sporotrichoid pattern is a key diagnostic clue for identifying sporotrichosis but was absent at the time our patient presented for medical care. Rather, the sporotrichoid spread seemed to have occurred in a centrifugal fashion up the leg. Few case reports have documented an annular presentation of lymphocutaneous sporotrichosis,^8-13 and one report described central atrophy and hypopigmentation.¹⁰ Pain and pruritus, which were present in our patient, rarely are documented.⁹ Finally, the diagnosis of cutaneous fungal infections may require multiple biopsies due to the variable abundance of viable organisms in tissue specimens as well as the fastidious growth characteristics of these organisms. Furthermore, sensitivity often is low for both fungal and mycobacterial cultures, and cultures may take days to weeks to yield growth.^14,15 For these reasons, empiric therapy and repeat biopsies often are pursued if clinical suspicion is high enough.¹⁶ Our patient returned for multiple scouting biopsies after the initial tissue culture was negative and was even considered for empiric treatment against Mycobacterium prior to positive fungal cultures.

Another unique aspect of our case was the presence of a keloid. It is difficult to know if this keloid was secondary to the trauma the patient sustained in the inciting incident or formed from the fungal infection. Interestingly, it has been hypothesized that fungal infections may contribute to keloid and hypertrophic scar formation.¹⁷ In a case series of 3 patients with either keloids or hypertrophic scars and concomitant tinea infection, there was notable improvement in the appearance of the scars 2 weeks after beginning itraconazole therapy.¹⁷ However, it is not yet known if a fungal infection can contribute to the pathogenesis of keloid formation.

As with other aspects of this case, the length of time the patient went without diagnosis and treatment was unusual and may help explain the atypical presentation. Although the incubation period for S schenckii can vary, most reports identify patients as seeking medical attention within 1 year of rash onset.^18-20 In our case, the patient was not diagnosed until 8 years after his symptoms began, requiring multiple referrals, multiple health system touchpoints, and an institution-specific financial aid program. As such, this case also highlights the potential need for a multidisciplinary team approach when caring for patients with poor access to health care.

In conclusion, this case illustrates a unique presentation of lymphocutaneous sporotrichosis that may mimic other chronic infections and result in delayed diagnosis. Although lymphangitic sporotrichosis generally is recognized as having a linear distribution, mounting evidence from this report and others suggests an annular presentation also is possible. Pruritus or pain is rare but should not preclude a diagnosis of sporotrichosis if present. For patients with limited access to health care resources, it is especially important to involve multiple members of the health care team, including social workers and specialists, to prevent a protracted and severe course of disease.

To the Editor:

Sporotrichosis refers to a subacute to chronic fungal infection that usually involves the cutaneous and subcutaneous tissues and is caused by the introduction of Sporothrix, a dimorphic fungus, through the skin. We present a case of chronic atypical lymphocutaneous sporotrichosis.

A 46-year-old man presented to the outpatient dermatology clinic for follow-up for a rash on the right leg that spread to the thigh and became painful and pruritic. It initially developed 8 years prior to the current presentation after he sustained trauma to the leg from an electroshock weapon. One year prior to the current presentation, he had presented to the emergency department and was prescribed doxycycline 100 mg twice daily for 7 days as well as bacitracin ointment. He also was instructed to follow up with dermatology, but a lack of health insurance and other socioeconomic barriers prevented him from seeking dermatologic care. Nine months later, he again presented to the emergency department due to a motor vehicle accident. Computed tomography (CT) of the right leg revealed exophytic dermal masses, inflammatory stranding of the subcutaneous tissue, and right inguinal lymph nodes measuring up to 1.4 cm; there was no osteoarticular involvement. At that time, the patient was applying gentian violet to the skin lesions and taking hydroxyzine 50 mg 3 times daily as needed for pruritus with minimal relief. Financial support was provided for follow-up with dermatology, which occurred almost 5 months later.

At the current presentation, physical examination revealed a large annular plaque with verrucous, scaly, erythematous borders and a hypopigmented atrophic center extending from the medial aspect of the right leg to the posterior thigh. Numerous pink, scaly, crusted nodules were scattered primarily along the periphery, with some evidence of draining sinus tracts. In addition, a fibrotic pink linear plaque extended from the medial right leg to the popliteal fossa, consistent with a keloid. Violet staining along the periphery of the lesion also was appreciated secondary to the application of topical gentian violet (Figure 1).

Based on the chronic history and morphology, a diagnosis of a chronic fungal or atypical mycobacterial infection was favored. In particular, chromoblastomycosis, cutaneous tuberculosis (eg, scrofuloderma, lupus vulgaris, tuberculosis verrucosa cutis), and atypical mycobacterial infection were highest on the differential, as these conditions often exhibit annular, nodular, verrucous, and/or atrophic lesions. The nodularity, crusting, and draining sinus tracts also raised the possibility of mycetoma. Given the extension of the lesion from the lower to upper leg, a sporotrichoid infection also was considered but was thought to be less likely based on the annular configuration.

Two 4-mm punch biopsies were taken from a peripheral nodule—one for routine histology and another for bacterial, fungal, and mycobacterial cultures. An ­interferon-gamma release assay also was ordered to evaluate for immune responses indicative of prior Mycobacterium tuberculosis infection, but the patient did not obtain this for unknown reasons. Histology demonstrated pseudoepitheliomatous hyperplasia and necrotizing granulomas, which suggested an infectious etiology, but no organisms were identified on tissue staining and all cultures were negative for growth at 6 weeks. The patient was asked to return at that point, and 4 additional scouting biopsies were performed and sent for routine histology, M tuberculosis nucleic acid amplification testing, and microbiologic cultures (ie, bacterial, mycobacterial, fungal, nocardia, actinomycetes). Within 1 week, a filamentous organism with pigmentation visible on the front and back of a Sabouraud dextrose agar plate was identified on fungal culture (Figure 2). Microscopic evaluation of this mold with lactophenol blue stain revealed thin septate hyphae with conidiophores arising at right angles that bore clusters of microconidia (Figure 3). Sequencing analysis ultimately identified this organism as Sporothrix schenckii. Routine histology demonstrated pseudoepitheliomatous hyperplasia with scattered intraepidermal collections of neutrophils (Figure 4). The dermis showed a dense, superficial, and deep infiltrate composed of lymphocytes, histiocytes, and plasma cells with occasional neutrophils and eosinophils. A Grocott-Gomori methenamine-silver stain revealed a cluster of ovoid yeast forms within the stratum corneum (Figure 5). The patient was referred to infectious disease for follow-up and treatment.

The patient later visited a community clinic providing dermatologic care for patients without insurance. He was started on itraconazole 200 mg daily for a total of 6 months until dermatologic clearance of the cutaneous lesions was observed. He was followed by the clinic with laboratory tests including a liver function test. At follow-up 8 months later, a repeat biopsy was performed to ensure histologic clearance of the sporotrichosis, which revealed a dermal scar and no evidence of residual infection.

Sporothrix schenckii was first isolated in 1898 by Benjamin Schenck, a student at Johns Hopkins Medicine (Baltimore, Maryland), and identified by a mycologist as sporotricha.¹ Species within the genus Sporothrix are unique in that the fungi are both dimorphic (growing as a mold at 25 °C but as a yeast at 37 °C) and dematiaceous (dark pigmentation from melanin is visible on inspection of the anterior and reverse sides of culture plates). Infection usually occurs when cutaneous or subcutaneous tissues are exposed to the fungus via microabrasions; activities thought to contribute to exposure include gardening, agricultural work, animal husbandry, and feline scratches.² Although skin trauma frequently is considered the primary route of infection, patient recall is variable, with one study noting that only 37.7% of patients recalled trauma and another study similarly demonstrating a patient recall rate of 25%.^3,4

Lymphocutaneous sporotrichosis is the most common presentation of the fungal infection,⁵ and clinical cases may be classified into 1 of 4 categories: (1) lymphangitic lesions—papules at the site of inoculation with spread along the lymphatic channels; (2) localized (fixed) cutaneous lesions—1 or 2 lesions at the inoculation site; (3) disseminated (multifocal) cutaneous lesions; and (4) extracutaneous lesions.⁶ Extracutaneous manifestations of this infection most notably have been reported as pulmonary disease through inhalation of conidia or through dissemination in immunocompromised hosts.⁷ Our patient’s infection was categorized as lymphangitic lesions due to spread from the lower to upper leg, albeit in a highly atypical, annular fashion. A review of systems was otherwise negative, and CT ruled out osteoarticular involvement.

In addition to socioeconomic barriers, several factors contributed to a delayed diagnosis in this patient including the annular presentation with central hypopigmentation and atrophy, negative initial microbiological cultures and lack of visualization of organisms on histopathology, and the consequent need for repeat biopsies. For lymphocutaneous sporotrichosis, the typical presentation consists of a papule or ulcerated nodule at the site of inoculation with subsequent linear spread along lymphatic channels. This classic sporotrichoid pattern is a key diagnostic clue for identifying sporotrichosis but was absent at the time our patient presented for medical care. Rather, the sporotrichoid spread seemed to have occurred in a centrifugal fashion up the leg. Few case reports have documented an annular presentation of lymphocutaneous sporotrichosis,^8-13 and one report described central atrophy and hypopigmentation.¹⁰ Pain and pruritus, which were present in our patient, rarely are documented.⁹ Finally, the diagnosis of cutaneous fungal infections may require multiple biopsies due to the variable abundance of viable organisms in tissue specimens as well as the fastidious growth characteristics of these organisms. Furthermore, sensitivity often is low for both fungal and mycobacterial cultures, and cultures may take days to weeks to yield growth.^14,15 For these reasons, empiric therapy and repeat biopsies often are pursued if clinical suspicion is high enough.¹⁶ Our patient returned for multiple scouting biopsies after the initial tissue culture was negative and was even considered for empiric treatment against Mycobacterium prior to positive fungal cultures.

Another unique aspect of our case was the presence of a keloid. It is difficult to know if this keloid was secondary to the trauma the patient sustained in the inciting incident or formed from the fungal infection. Interestingly, it has been hypothesized that fungal infections may contribute to keloid and hypertrophic scar formation.¹⁷ In a case series of 3 patients with either keloids or hypertrophic scars and concomitant tinea infection, there was notable improvement in the appearance of the scars 2 weeks after beginning itraconazole therapy.¹⁷ However, it is not yet known if a fungal infection can contribute to the pathogenesis of keloid formation.

As with other aspects of this case, the length of time the patient went without diagnosis and treatment was unusual and may help explain the atypical presentation. Although the incubation period for S schenckii can vary, most reports identify patients as seeking medical attention within 1 year of rash onset.^18-20 In our case, the patient was not diagnosed until 8 years after his symptoms began, requiring multiple referrals, multiple health system touchpoints, and an institution-specific financial aid program. As such, this case also highlights the potential need for a multidisciplinary team approach when caring for patients with poor access to health care.

In conclusion, this case illustrates a unique presentation of lymphocutaneous sporotrichosis that may mimic other chronic infections and result in delayed diagnosis. Although lymphangitic sporotrichosis generally is recognized as having a linear distribution, mounting evidence from this report and others suggests an annular presentation also is possible. Pruritus or pain is rare but should not preclude a diagnosis of sporotrichosis if present. For patients with limited access to health care resources, it is especially important to involve multiple members of the health care team, including social workers and specialists, to prevent a protracted and severe course of disease.

To the Editor:

Sporotrichosis refers to a subacute to chronic fungal infection that usually involves the cutaneous and subcutaneous tissues and is caused by the introduction of Sporothrix, a dimorphic fungus, through the skin. We present a case of chronic atypical lymphocutaneous sporotrichosis.

A 46-year-old man presented to the outpatient dermatology clinic for follow-up for a rash on the right leg that spread to the thigh and became painful and pruritic. It initially developed 8 years prior to the current presentation after he sustained trauma to the leg from an electroshock weapon. One year prior to the current presentation, he had presented to the emergency department and was prescribed doxycycline 100 mg twice daily for 7 days as well as bacitracin ointment. He also was instructed to follow up with dermatology, but a lack of health insurance and other socioeconomic barriers prevented him from seeking dermatologic care. Nine months later, he again presented to the emergency department due to a motor vehicle accident. Computed tomography (CT) of the right leg revealed exophytic dermal masses, inflammatory stranding of the subcutaneous tissue, and right inguinal lymph nodes measuring up to 1.4 cm; there was no osteoarticular involvement. At that time, the patient was applying gentian violet to the skin lesions and taking hydroxyzine 50 mg 3 times daily as needed for pruritus with minimal relief. Financial support was provided for follow-up with dermatology, which occurred almost 5 months later.

At the current presentation, physical examination revealed a large annular plaque with verrucous, scaly, erythematous borders and a hypopigmented atrophic center extending from the medial aspect of the right leg to the posterior thigh. Numerous pink, scaly, crusted nodules were scattered primarily along the periphery, with some evidence of draining sinus tracts. In addition, a fibrotic pink linear plaque extended from the medial right leg to the popliteal fossa, consistent with a keloid. Violet staining along the periphery of the lesion also was appreciated secondary to the application of topical gentian violet (Figure 1).

Based on the chronic history and morphology, a diagnosis of a chronic fungal or atypical mycobacterial infection was favored. In particular, chromoblastomycosis, cutaneous tuberculosis (eg, scrofuloderma, lupus vulgaris, tuberculosis verrucosa cutis), and atypical mycobacterial infection were highest on the differential, as these conditions often exhibit annular, nodular, verrucous, and/or atrophic lesions. The nodularity, crusting, and draining sinus tracts also raised the possibility of mycetoma. Given the extension of the lesion from the lower to upper leg, a sporotrichoid infection also was considered but was thought to be less likely based on the annular configuration.

Two 4-mm punch biopsies were taken from a peripheral nodule—one for routine histology and another for bacterial, fungal, and mycobacterial cultures. An ­interferon-gamma release assay also was ordered to evaluate for immune responses indicative of prior Mycobacterium tuberculosis infection, but the patient did not obtain this for unknown reasons. Histology demonstrated pseudoepitheliomatous hyperplasia and necrotizing granulomas, which suggested an infectious etiology, but no organisms were identified on tissue staining and all cultures were negative for growth at 6 weeks. The patient was asked to return at that point, and 4 additional scouting biopsies were performed and sent for routine histology, M tuberculosis nucleic acid amplification testing, and microbiologic cultures (ie, bacterial, mycobacterial, fungal, nocardia, actinomycetes). Within 1 week, a filamentous organism with pigmentation visible on the front and back of a Sabouraud dextrose agar plate was identified on fungal culture (Figure 2). Microscopic evaluation of this mold with lactophenol blue stain revealed thin septate hyphae with conidiophores arising at right angles that bore clusters of microconidia (Figure 3). Sequencing analysis ultimately identified this organism as Sporothrix schenckii. Routine histology demonstrated pseudoepitheliomatous hyperplasia with scattered intraepidermal collections of neutrophils (Figure 4). The dermis showed a dense, superficial, and deep infiltrate composed of lymphocytes, histiocytes, and plasma cells with occasional neutrophils and eosinophils. A Grocott-Gomori methenamine-silver stain revealed a cluster of ovoid yeast forms within the stratum corneum (Figure 5). The patient was referred to infectious disease for follow-up and treatment.

The patient later visited a community clinic providing dermatologic care for patients without insurance. He was started on itraconazole 200 mg daily for a total of 6 months until dermatologic clearance of the cutaneous lesions was observed. He was followed by the clinic with laboratory tests including a liver function test. At follow-up 8 months later, a repeat biopsy was performed to ensure histologic clearance of the sporotrichosis, which revealed a dermal scar and no evidence of residual infection.

Sporothrix schenckii was first isolated in 1898 by Benjamin Schenck, a student at Johns Hopkins Medicine (Baltimore, Maryland), and identified by a mycologist as sporotricha.¹ Species within the genus Sporothrix are unique in that the fungi are both dimorphic (growing as a mold at 25 °C but as a yeast at 37 °C) and dematiaceous (dark pigmentation from melanin is visible on inspection of the anterior and reverse sides of culture plates). Infection usually occurs when cutaneous or subcutaneous tissues are exposed to the fungus via microabrasions; activities thought to contribute to exposure include gardening, agricultural work, animal husbandry, and feline scratches.² Although skin trauma frequently is considered the primary route of infection, patient recall is variable, with one study noting that only 37.7% of patients recalled trauma and another study similarly demonstrating a patient recall rate of 25%.^3,4

Lymphocutaneous sporotrichosis is the most common presentation of the fungal infection,⁵ and clinical cases may be classified into 1 of 4 categories: (1) lymphangitic lesions—papules at the site of inoculation with spread along the lymphatic channels; (2) localized (fixed) cutaneous lesions—1 or 2 lesions at the inoculation site; (3) disseminated (multifocal) cutaneous lesions; and (4) extracutaneous lesions.⁶ Extracutaneous manifestations of this infection most notably have been reported as pulmonary disease through inhalation of conidia or through dissemination in immunocompromised hosts.⁷ Our patient’s infection was categorized as lymphangitic lesions due to spread from the lower to upper leg, albeit in a highly atypical, annular fashion. A review of systems was otherwise negative, and CT ruled out osteoarticular involvement.

In addition to socioeconomic barriers, several factors contributed to a delayed diagnosis in this patient including the annular presentation with central hypopigmentation and atrophy, negative initial microbiological cultures and lack of visualization of organisms on histopathology, and the consequent need for repeat biopsies. For lymphocutaneous sporotrichosis, the typical presentation consists of a papule or ulcerated nodule at the site of inoculation with subsequent linear spread along lymphatic channels. This classic sporotrichoid pattern is a key diagnostic clue for identifying sporotrichosis but was absent at the time our patient presented for medical care. Rather, the sporotrichoid spread seemed to have occurred in a centrifugal fashion up the leg. Few case reports have documented an annular presentation of lymphocutaneous sporotrichosis,^8-13 and one report described central atrophy and hypopigmentation.¹⁰ Pain and pruritus, which were present in our patient, rarely are documented.⁹ Finally, the diagnosis of cutaneous fungal infections may require multiple biopsies due to the variable abundance of viable organisms in tissue specimens as well as the fastidious growth characteristics of these organisms. Furthermore, sensitivity often is low for both fungal and mycobacterial cultures, and cultures may take days to weeks to yield growth.^14,15 For these reasons, empiric therapy and repeat biopsies often are pursued if clinical suspicion is high enough.¹⁶ Our patient returned for multiple scouting biopsies after the initial tissue culture was negative and was even considered for empiric treatment against Mycobacterium prior to positive fungal cultures.

Another unique aspect of our case was the presence of a keloid. It is difficult to know if this keloid was secondary to the trauma the patient sustained in the inciting incident or formed from the fungal infection. Interestingly, it has been hypothesized that fungal infections may contribute to keloid and hypertrophic scar formation.¹⁷ In a case series of 3 patients with either keloids or hypertrophic scars and concomitant tinea infection, there was notable improvement in the appearance of the scars 2 weeks after beginning itraconazole therapy.¹⁷ However, it is not yet known if a fungal infection can contribute to the pathogenesis of keloid formation.

As with other aspects of this case, the length of time the patient went without diagnosis and treatment was unusual and may help explain the atypical presentation. Although the incubation period for S schenckii can vary, most reports identify patients as seeking medical attention within 1 year of rash onset.^18-20 In our case, the patient was not diagnosed until 8 years after his symptoms began, requiring multiple referrals, multiple health system touchpoints, and an institution-specific financial aid program. As such, this case also highlights the potential need for a multidisciplinary team approach when caring for patients with poor access to health care.

In conclusion, this case illustrates a unique presentation of lymphocutaneous sporotrichosis that may mimic other chronic infections and result in delayed diagnosis. Although lymphangitic sporotrichosis generally is recognized as having a linear distribution, mounting evidence from this report and others suggests an annular presentation also is possible. Pruritus or pain is rare but should not preclude a diagnosis of sporotrichosis if present. For patients with limited access to health care resources, it is especially important to involve multiple members of the health care team, including social workers and specialists, to prevent a protracted and severe course of disease.

To the Editor:

Eosinophilic pustular folliculitis (EPF) is a noninfectious dermatosis that typically manifests as recurrent follicular papulopustules that generally affect the face and occasionally the trunk and arms. There are several subtypes of EPF: classic EPF (Ofuji disease), infancy-associated EPF, and immunosuppression-associated EPF.^1,2 We report a rare case of EPF in the setting of untreated chronic lymphocytic leukemia (CLL), a subtype of immunosuppression­-associated EPF that has been associated with hematologic malignancy EPF (HM-EPF).^3-5

A 69-year-old woman presented with diffusely scattered, pruritic, erythematous, erosive lesions on the back, arms, legs, and forehead (Figure 1) of 4 months’ duration, as well as an ulcerative lesion on the left third toe due to a suspected insect bite. She had a history of untreated CLL that was diagnosed 2 years prior. The patient was empirically started on clindamycin for presumed infection of the toe. A punch biopsy of the left wrist revealed superficial and deep dermal perivascular and interstitial inflammatory infiltrates composed of lymphocytes, histiocytes, and numerous eosinophils in association with edema and necrosis. Histopathology was overall most consistent with an exuberant arthropod reaction; however, at 2-week follow-up, the patient reported that the pustular lesions improved upon starting antibiotics, which raised concerns for a bacterial process. The patient initially was continued on clindamycin given subjective improvement but was later switched to daptomycin, as she developed clindamycin-resistant methicillin-resistant Staphylococcus aureus osteomyelitis from the necrotic toe.

A month later, the patient returned with new papules and pustules on the arms and trunk. A repeat biopsy showed notable dermal collections comprised predominantly of neutrophils and eosinophils as well as involvement of follicular structures by dense inflammation (Figure 2). Immunohistochemistry demonstrated a predominant population of small CD3⁺ T cells, which raised concern for cutaneous T-cell lymphoma. However, retention of CD5 expression made this less likely. Few scattered CD20⁺ B cells with limited CD23 reactivity and without CD5 co-expression were detected, which ruled out cutaneous involvement of the patient’s CLL. Bacterial culture and Grocott methenamine-silver, Gram, acid-fast bacilli, and periodic acid-Schiff stains were negative. Polymerase chain reaction testing for varicella-zoster virus and herpes simplex virus also were negative. Thus, a diagnosis of EPF secondary to CLL was favored, as an infectious process also was unlikely. The patient was started on triamcinolone cream 0.1% with gradual improvement.

Cases of HM-EPF predominantly have been reported in patients who have undergone chemotherapy, bone marrow transplantation, or hematopoietic stem cell transplantation. Furthermore, a vast majority of these cases have been reported in older males.^3-16 In a retrospective study of more than 750 patients with established CLL, Agnew et al⁷ identified 125 different skin complications in 40 patients. Of this subset, only a small number (2/40) were associated with eosinophilic folliculitis, with 1 case noted in a middle-aged woman with a history of CLL treatment.⁷ Moreover, Motaparthi et al⁴ reported 3 additional cases of HM-EPF, with all patients identified as middle-aged men who were treated with chemotherapy for underlying CLL. Our patient represents a case of EPF in the context of untreated CLL in a woman.

Although topical corticosteroids remain the first-line treatment for EPF, a survey study conducted across 67 hospitals in Japan indicated that antibiotics were moderately or highly effective in 79% of EPF patients (n=143).¹⁷ This association may explain the subjective improvement reported by our patient upon starting clindamycin. Furthermore, in HIV-associated EPF, high-dose cetirizine, itraconazole, and metronidazole have been successful when topical therapies have failed.¹⁸ Although the precise pathogenesis of EPF is unknown, histopathologic features, clinical appearance, and identification of the accurate EPF subtype can still prove valuable in informing empiric treatment strategies. Consequently, the initial histopathologic diagnosis of an arthropod bite reaction in our patient highlights the importance of clinical correlation and additional ancillary studies in the determination of EPF vs other inflammatory dermatoses that manifest microscopically with lymphocytic infiltrates, prominent eosinophils, and follicular involvement.⁴ The histopathologic features of EPF demonstrate considerable overlap with eosinophilic dermatosis of hematologic malignancy (also known as eosinophilic dermatosis of myeloproliferative disease). It is suspected that eosinophilic dermatosis of hematologic malignancy and EPF may exist on a spectrum, and additional cases may improve categorization of these entities.¹⁹

In conclusion, this report adds to the medical practitioner’s awareness of EPF manifestations in patients with underlying CLL, an infrequently reported subtype of HM-EPF.

To the Editor:

Eosinophilic pustular folliculitis (EPF) is a noninfectious dermatosis that typically manifests as recurrent follicular papulopustules that generally affect the face and occasionally the trunk and arms. There are several subtypes of EPF: classic EPF (Ofuji disease), infancy-associated EPF, and immunosuppression-associated EPF.^1,2 We report a rare case of EPF in the setting of untreated chronic lymphocytic leukemia (CLL), a subtype of immunosuppression­-associated EPF that has been associated with hematologic malignancy EPF (HM-EPF).^3-5

A 69-year-old woman presented with diffusely scattered, pruritic, erythematous, erosive lesions on the back, arms, legs, and forehead (Figure 1) of 4 months’ duration, as well as an ulcerative lesion on the left third toe due to a suspected insect bite. She had a history of untreated CLL that was diagnosed 2 years prior. The patient was empirically started on clindamycin for presumed infection of the toe. A punch biopsy of the left wrist revealed superficial and deep dermal perivascular and interstitial inflammatory infiltrates composed of lymphocytes, histiocytes, and numerous eosinophils in association with edema and necrosis. Histopathology was overall most consistent with an exuberant arthropod reaction; however, at 2-week follow-up, the patient reported that the pustular lesions improved upon starting antibiotics, which raised concerns for a bacterial process. The patient initially was continued on clindamycin given subjective improvement but was later switched to daptomycin, as she developed clindamycin-resistant methicillin-resistant Staphylococcus aureus osteomyelitis from the necrotic toe.

A month later, the patient returned with new papules and pustules on the arms and trunk. A repeat biopsy showed notable dermal collections comprised predominantly of neutrophils and eosinophils as well as involvement of follicular structures by dense inflammation (Figure 2). Immunohistochemistry demonstrated a predominant population of small CD3⁺ T cells, which raised concern for cutaneous T-cell lymphoma. However, retention of CD5 expression made this less likely. Few scattered CD20⁺ B cells with limited CD23 reactivity and without CD5 co-expression were detected, which ruled out cutaneous involvement of the patient’s CLL. Bacterial culture and Grocott methenamine-silver, Gram, acid-fast bacilli, and periodic acid-Schiff stains were negative. Polymerase chain reaction testing for varicella-zoster virus and herpes simplex virus also were negative. Thus, a diagnosis of EPF secondary to CLL was favored, as an infectious process also was unlikely. The patient was started on triamcinolone cream 0.1% with gradual improvement.

Cases of HM-EPF predominantly have been reported in patients who have undergone chemotherapy, bone marrow transplantation, or hematopoietic stem cell transplantation. Furthermore, a vast majority of these cases have been reported in older males.^3-16 In a retrospective study of more than 750 patients with established CLL, Agnew et al⁷ identified 125 different skin complications in 40 patients. Of this subset, only a small number (2/40) were associated with eosinophilic folliculitis, with 1 case noted in a middle-aged woman with a history of CLL treatment.⁷ Moreover, Motaparthi et al⁴ reported 3 additional cases of HM-EPF, with all patients identified as middle-aged men who were treated with chemotherapy for underlying CLL. Our patient represents a case of EPF in the context of untreated CLL in a woman.

Although topical corticosteroids remain the first-line treatment for EPF, a survey study conducted across 67 hospitals in Japan indicated that antibiotics were moderately or highly effective in 79% of EPF patients (n=143).¹⁷ This association may explain the subjective improvement reported by our patient upon starting clindamycin. Furthermore, in HIV-associated EPF, high-dose cetirizine, itraconazole, and metronidazole have been successful when topical therapies have failed.¹⁸ Although the precise pathogenesis of EPF is unknown, histopathologic features, clinical appearance, and identification of the accurate EPF subtype can still prove valuable in informing empiric treatment strategies. Consequently, the initial histopathologic diagnosis of an arthropod bite reaction in our patient highlights the importance of clinical correlation and additional ancillary studies in the determination of EPF vs other inflammatory dermatoses that manifest microscopically with lymphocytic infiltrates, prominent eosinophils, and follicular involvement.⁴ The histopathologic features of EPF demonstrate considerable overlap with eosinophilic dermatosis of hematologic malignancy (also known as eosinophilic dermatosis of myeloproliferative disease). It is suspected that eosinophilic dermatosis of hematologic malignancy and EPF may exist on a spectrum, and additional cases may improve categorization of these entities.¹⁹

In conclusion, this report adds to the medical practitioner’s awareness of EPF manifestations in patients with underlying CLL, an infrequently reported subtype of HM-EPF.

To the Editor:

Eosinophilic pustular folliculitis (EPF) is a noninfectious dermatosis that typically manifests as recurrent follicular papulopustules that generally affect the face and occasionally the trunk and arms. There are several subtypes of EPF: classic EPF (Ofuji disease), infancy-associated EPF, and immunosuppression-associated EPF.^1,2 We report a rare case of EPF in the setting of untreated chronic lymphocytic leukemia (CLL), a subtype of immunosuppression­-associated EPF that has been associated with hematologic malignancy EPF (HM-EPF).^3-5

A 69-year-old woman presented with diffusely scattered, pruritic, erythematous, erosive lesions on the back, arms, legs, and forehead (Figure 1) of 4 months’ duration, as well as an ulcerative lesion on the left third toe due to a suspected insect bite. She had a history of untreated CLL that was diagnosed 2 years prior. The patient was empirically started on clindamycin for presumed infection of the toe. A punch biopsy of the left wrist revealed superficial and deep dermal perivascular and interstitial inflammatory infiltrates composed of lymphocytes, histiocytes, and numerous eosinophils in association with edema and necrosis. Histopathology was overall most consistent with an exuberant arthropod reaction; however, at 2-week follow-up, the patient reported that the pustular lesions improved upon starting antibiotics, which raised concerns for a bacterial process. The patient initially was continued on clindamycin given subjective improvement but was later switched to daptomycin, as she developed clindamycin-resistant methicillin-resistant Staphylococcus aureus osteomyelitis from the necrotic toe.

A month later, the patient returned with new papules and pustules on the arms and trunk. A repeat biopsy showed notable dermal collections comprised predominantly of neutrophils and eosinophils as well as involvement of follicular structures by dense inflammation (Figure 2). Immunohistochemistry demonstrated a predominant population of small CD3⁺ T cells, which raised concern for cutaneous T-cell lymphoma. However, retention of CD5 expression made this less likely. Few scattered CD20⁺ B cells with limited CD23 reactivity and without CD5 co-expression were detected, which ruled out cutaneous involvement of the patient’s CLL. Bacterial culture and Grocott methenamine-silver, Gram, acid-fast bacilli, and periodic acid-Schiff stains were negative. Polymerase chain reaction testing for varicella-zoster virus and herpes simplex virus also were negative. Thus, a diagnosis of EPF secondary to CLL was favored, as an infectious process also was unlikely. The patient was started on triamcinolone cream 0.1% with gradual improvement.

Cases of HM-EPF predominantly have been reported in patients who have undergone chemotherapy, bone marrow transplantation, or hematopoietic stem cell transplantation. Furthermore, a vast majority of these cases have been reported in older males.^3-16 In a retrospective study of more than 750 patients with established CLL, Agnew et al⁷ identified 125 different skin complications in 40 patients. Of this subset, only a small number (2/40) were associated with eosinophilic folliculitis, with 1 case noted in a middle-aged woman with a history of CLL treatment.⁷ Moreover, Motaparthi et al⁴ reported 3 additional cases of HM-EPF, with all patients identified as middle-aged men who were treated with chemotherapy for underlying CLL. Our patient represents a case of EPF in the context of untreated CLL in a woman.

Although topical corticosteroids remain the first-line treatment for EPF, a survey study conducted across 67 hospitals in Japan indicated that antibiotics were moderately or highly effective in 79% of EPF patients (n=143).¹⁷ This association may explain the subjective improvement reported by our patient upon starting clindamycin. Furthermore, in HIV-associated EPF, high-dose cetirizine, itraconazole, and metronidazole have been successful when topical therapies have failed.¹⁸ Although the precise pathogenesis of EPF is unknown, histopathologic features, clinical appearance, and identification of the accurate EPF subtype can still prove valuable in informing empiric treatment strategies. Consequently, the initial histopathologic diagnosis of an arthropod bite reaction in our patient highlights the importance of clinical correlation and additional ancillary studies in the determination of EPF vs other inflammatory dermatoses that manifest microscopically with lymphocytic infiltrates, prominent eosinophils, and follicular involvement.⁴ The histopathologic features of EPF demonstrate considerable overlap with eosinophilic dermatosis of hematologic malignancy (also known as eosinophilic dermatosis of myeloproliferative disease). It is suspected that eosinophilic dermatosis of hematologic malignancy and EPF may exist on a spectrum, and additional cases may improve categorization of these entities.¹⁹

In conclusion, this report adds to the medical practitioner’s awareness of EPF manifestations in patients with underlying CLL, an infrequently reported subtype of HM-EPF.

To the Editor:

Tinea capitis is a common childhood infection seen worldwide and is more prevalent in children of African descent.¹ Treatment can be effective; however, the diagnosis may be delayed due to variability in presentation, camouflage of scalp scale with ointment, and the diagnostic experience of the provider. A common complication of tinea capitis is the dermatophytid (id) reaction, which commonly manifests as multiple 1- to 2-mm monomorphic papules. We report a case of a papulosquamous variant of an id reaction secondary to tinea capitis.

An 8-year-old African American child presented with annular hyperpigmented patches on the face and trunk of several months’ duration. There was no preceding fever, illness, scalp pruritus, or alopecia according to the patient’s mother. The hyperpigmented patches persisted despite use of hydrocortisone and antifungal creams prescribed by a primary care provider. A fungal culture of a scalp specimen was negative. Physical examination during the initial dermatology visit revealed multiple annular hyperpigmented patches on the trunk and extremities. No plaques were evident; however, the mother reported that when the lesions first developed, they were raised and mildly pruritic. The patient was prescribed triamcinolone ointment 0.1% twice daily as needed for itching, and sun protection was emphasized.

At the follow-up visit weeks later, the patient’s mother reported that the ointment had helped the lesions resolve faster, but new lesions continued to appear. Physical examination at this visit was notable for scattered hyperpigmented patches, annular hyperpigmented plaques, and erythematous plaques on the trunk, arms, and legs, in addition to papulosquamous plaques and hyperpigmented patches on the forehead (Figure 1). Suspicion for tinea capitis was discussed, a repeat scalp fungal culture was performed, and oral terbinafine 250 mg once daily was started empirically. The culture was positive for Trichophyton tonsurans supporting the diagnosis of concomitant tinea capitis. The rash resolved with terbinafine, and annular patches of postinflammatory hyperpigmentation remained.

Dermatophytid reactions are immunologically mediated, disseminated, eczematous eruptions occurring after cutaneous infections or inflammatory skin conditions. Reactions occur days to weeks after exposure to antigens of dermatophytes causing tinea pedis or capitis.²

Common culprits include Microsporum canis and T tonsurans.³ Dermatophytid reactions with tinea capitis exhibit morphologic variability including a symmetric distribution of grouped or diffuse,⁴ pruritic, erythematous or flesh-colored, follicular papules on the trunk, with or without progression to the face, torso, upper extremities, and/or lower extremities.³ Other reported manifestations include erythema multiforme, erythema nodosum,³ or lupuslike lesions, and crops of dyshidrotic vesicles on the hands in the setting of Trichophyton mentagrophytes–induced tinea pedis.⁵

The papulosquamous variant id reaction should be considered in a wider differential that includes psoriasis, nummular eczema, and pityriasis rosea. Unlike psoriasis, the id reaction is not chronic and responds to systemic antifungal therapy. Nummular eczema can be ruled out, though not entirely, by a lack of personal or family history of atopy. The characteristic cleavage lines of pityriasis rosea on the trunk are absent in patients with an id reaction, and there would be no preceding illness or herald patches seen in the id reaction.

Tinea capitis may cause a variety of id manifestations, including the papulosquamous phenotype. This case addresses practice gaps that may lead to delayed diagnosis. It also highlights the importance of recognizing uncommon morphologies, performing repeat cultures of the scalp after a negative fungal culture, and lowering the threshold of suspicion for tinea capitis in the appropriate age group and demographic, specifically pediatric patients of African descent.

To the Editor:

Tinea capitis is a common childhood infection seen worldwide and is more prevalent in children of African descent.¹ Treatment can be effective; however, the diagnosis may be delayed due to variability in presentation, camouflage of scalp scale with ointment, and the diagnostic experience of the provider. A common complication of tinea capitis is the dermatophytid (id) reaction, which commonly manifests as multiple 1- to 2-mm monomorphic papules. We report a case of a papulosquamous variant of an id reaction secondary to tinea capitis.

An 8-year-old African American child presented with annular hyperpigmented patches on the face and trunk of several months’ duration. There was no preceding fever, illness, scalp pruritus, or alopecia according to the patient’s mother. The hyperpigmented patches persisted despite use of hydrocortisone and antifungal creams prescribed by a primary care provider. A fungal culture of a scalp specimen was negative. Physical examination during the initial dermatology visit revealed multiple annular hyperpigmented patches on the trunk and extremities. No plaques were evident; however, the mother reported that when the lesions first developed, they were raised and mildly pruritic. The patient was prescribed triamcinolone ointment 0.1% twice daily as needed for itching, and sun protection was emphasized.

At the follow-up visit weeks later, the patient’s mother reported that the ointment had helped the lesions resolve faster, but new lesions continued to appear. Physical examination at this visit was notable for scattered hyperpigmented patches, annular hyperpigmented plaques, and erythematous plaques on the trunk, arms, and legs, in addition to papulosquamous plaques and hyperpigmented patches on the forehead (Figure 1). Suspicion for tinea capitis was discussed, a repeat scalp fungal culture was performed, and oral terbinafine 250 mg once daily was started empirically. The culture was positive for Trichophyton tonsurans supporting the diagnosis of concomitant tinea capitis. The rash resolved with terbinafine, and annular patches of postinflammatory hyperpigmentation remained.

Dermatophytid reactions are immunologically mediated, disseminated, eczematous eruptions occurring after cutaneous infections or inflammatory skin conditions. Reactions occur days to weeks after exposure to antigens of dermatophytes causing tinea pedis or capitis.²

Common culprits include Microsporum canis and T tonsurans.³ Dermatophytid reactions with tinea capitis exhibit morphologic variability including a symmetric distribution of grouped or diffuse,⁴ pruritic, erythematous or flesh-colored, follicular papules on the trunk, with or without progression to the face, torso, upper extremities, and/or lower extremities.³ Other reported manifestations include erythema multiforme, erythema nodosum,³ or lupuslike lesions, and crops of dyshidrotic vesicles on the hands in the setting of Trichophyton mentagrophytes–induced tinea pedis.⁵

The papulosquamous variant id reaction should be considered in a wider differential that includes psoriasis, nummular eczema, and pityriasis rosea. Unlike psoriasis, the id reaction is not chronic and responds to systemic antifungal therapy. Nummular eczema can be ruled out, though not entirely, by a lack of personal or family history of atopy. The characteristic cleavage lines of pityriasis rosea on the trunk are absent in patients with an id reaction, and there would be no preceding illness or herald patches seen in the id reaction.

Tinea capitis may cause a variety of id manifestations, including the papulosquamous phenotype. This case addresses practice gaps that may lead to delayed diagnosis. It also highlights the importance of recognizing uncommon morphologies, performing repeat cultures of the scalp after a negative fungal culture, and lowering the threshold of suspicion for tinea capitis in the appropriate age group and demographic, specifically pediatric patients of African descent.

To the Editor:

Tinea capitis is a common childhood infection seen worldwide and is more prevalent in children of African descent.¹ Treatment can be effective; however, the diagnosis may be delayed due to variability in presentation, camouflage of scalp scale with ointment, and the diagnostic experience of the provider. A common complication of tinea capitis is the dermatophytid (id) reaction, which commonly manifests as multiple 1- to 2-mm monomorphic papules. We report a case of a papulosquamous variant of an id reaction secondary to tinea capitis.

An 8-year-old African American child presented with annular hyperpigmented patches on the face and trunk of several months’ duration. There was no preceding fever, illness, scalp pruritus, or alopecia according to the patient’s mother. The hyperpigmented patches persisted despite use of hydrocortisone and antifungal creams prescribed by a primary care provider. A fungal culture of a scalp specimen was negative. Physical examination during the initial dermatology visit revealed multiple annular hyperpigmented patches on the trunk and extremities. No plaques were evident; however, the mother reported that when the lesions first developed, they were raised and mildly pruritic. The patient was prescribed triamcinolone ointment 0.1% twice daily as needed for itching, and sun protection was emphasized.

At the follow-up visit weeks later, the patient’s mother reported that the ointment had helped the lesions resolve faster, but new lesions continued to appear. Physical examination at this visit was notable for scattered hyperpigmented patches, annular hyperpigmented plaques, and erythematous plaques on the trunk, arms, and legs, in addition to papulosquamous plaques and hyperpigmented patches on the forehead (Figure 1). Suspicion for tinea capitis was discussed, a repeat scalp fungal culture was performed, and oral terbinafine 250 mg once daily was started empirically. The culture was positive for Trichophyton tonsurans supporting the diagnosis of concomitant tinea capitis. The rash resolved with terbinafine, and annular patches of postinflammatory hyperpigmentation remained.

Dermatophytid reactions are immunologically mediated, disseminated, eczematous eruptions occurring after cutaneous infections or inflammatory skin conditions. Reactions occur days to weeks after exposure to antigens of dermatophytes causing tinea pedis or capitis.²

Common culprits include Microsporum canis and T tonsurans.³ Dermatophytid reactions with tinea capitis exhibit morphologic variability including a symmetric distribution of grouped or diffuse,⁴ pruritic, erythematous or flesh-colored, follicular papules on the trunk, with or without progression to the face, torso, upper extremities, and/or lower extremities.³ Other reported manifestations include erythema multiforme, erythema nodosum,³ or lupuslike lesions, and crops of dyshidrotic vesicles on the hands in the setting of Trichophyton mentagrophytes–induced tinea pedis.⁵

The papulosquamous variant id reaction should be considered in a wider differential that includes psoriasis, nummular eczema, and pityriasis rosea. Unlike psoriasis, the id reaction is not chronic and responds to systemic antifungal therapy. Nummular eczema can be ruled out, though not entirely, by a lack of personal or family history of atopy. The characteristic cleavage lines of pityriasis rosea on the trunk are absent in patients with an id reaction, and there would be no preceding illness or herald patches seen in the id reaction.

Tinea capitis may cause a variety of id manifestations, including the papulosquamous phenotype. This case addresses practice gaps that may lead to delayed diagnosis. It also highlights the importance of recognizing uncommon morphologies, performing repeat cultures of the scalp after a negative fungal culture, and lowering the threshold of suspicion for tinea capitis in the appropriate age group and demographic, specifically pediatric patients of African descent.

To the Editor:

Cases of primary varicella-zoster virus (VZV) are relatively uncommon in the United States since the introduction of the varicella vaccine in 1995, with an overall decline in cases of more than 97%.¹ Prior to the vaccine, 70% of hospitalizations occurred in children; subsequently, hospitalizations among the pediatric population (aged ≤20 years) declined by 97%. Compared to children, adults and immunocompromised patients with VZV infection may present with more severe disease and experience more complications.¹

Most children in the United States are vaccinated against VZV, with 90.3% receiving at least 1 dose by 24 months of age.² However, many countries do not implement universal varicella vaccination for infants.³ As a result, physicians should remember to include primary varicella in the differential when clinically correlated, especially when evaluating patients who have immigrated to the United States or who may be living in unvaccinated communities. We report 2 cases of primary VZV manifesting in adults to remind readers of the salient clinical features of this disease and how dermatologists play a critical role in early and accurate identification of diseases that can have wide-reaching public health implications.

A 26-year-old man with no relevant medical history presented to the emergency department with an itchy and painful rash of 5 days’ duration that began on the trunk and spread to the face, lips, feet, hands, arms, and legs. He also reported shortness of breath, cough, and chills, and he had a temperature of 100.8 °F (38.2 °C). Physical examination revealed numerous erythematous papules and vesiculopustules, some with central umbilication and some with overlying gold crusts (Figure 1).

Later that day, a 47-year-old man with no relevant medical history presented to the same emergency department with a rash along with self-reported fever and sore throat of 3 days’ duration. Physical examination found innumerable erythematous vesicopustules scattered on the face, scalp, neck, trunk, arms, and legs, some with a “dew drop on a rose petal” appearance and some with overlying hemorrhagic crust (Figure 2).

Although infection was of primary concern for the first patient, the presentation of the second patient prompted specific concern for primary VZV infection in both patients, who were placed on airborne and contact isolation precautions.

Skin biopsies from both patients showed acantholytic blisters, hair follicle necrosis, and marked dermal inflammation (Figure 3). Herpetic viral changes were seen in keratinocytes, with steel-grey nuclei, multinucleated keratinocytes, and chromatin margination. An immunostain for VZV was diffusely positive, and VZV antibody IgG was positive (Figure 4).

Upon additional questioning, both patients reported recent exposure to VZV-like illnesses in family members without a history of international travel. Neither of the patients was sure of their vaccination status or prior infection history. Both patients received intravenous acyclovir 10 mg/kg administered every 8 hours. Both patients experienced improvement and were discharged after 3 days on oral valacyclovir (1 g 3 times daily for a 7-day treatment course).

The similar presentation and timing of these 2 VZV cases caused concern for an unidentified community outbreak. The infection control team was notified; additionally, per hospital protocol the state health department was alerted as well as the clinicians and staff of the hospital with a request to be vigilant for further cases.

Despite high vaccination rates in the United States, outbreaks of varicella still occur, particularly among unvaccinated individuals, and a robust and efficient response is necessary to control the spread of such outbreaks.⁴ Many states, including Arkansas where our cases occurred, have laws mandating report of VZV cases to the department of health.⁵ Dermatologists play an important role in reporting cases, aiding in diagnosis through recognition of the physical examination findings, obtaining appropriate biopsy, and recommending additional laboratory testing.

Typical skin manifestations include a pruritic rash of macules, papules, vesicles, and crusted lesions distributed throughout the trunk, face, arms, and legs. Because new lesions appear over several days, they will be in different stages of healing, resulting in the simultaneous presence of papules, vesicles, and crusted lesions.⁶ This unique characteristic helps distinguish VZV from other skin diseases such as smallpox or mpox (monkeypox), which generally show lesions in similar stages of evolution.

Biopsy also can aid in identification. Viruses in the herpes family reveal similar histopathologic characteristics, including acantholysis and vesicle formation, intranuclear inclusions with margination of chromatin, multinucleation, and nuclear molding.⁷ Immunohistochemistry can be used to differentiate VZV from herpes simplex virus; however, neither microscopic examination nor immunohistochemistry distinguish primary VZV infection from herpes zoster (HZ).⁸

The mpox rash progresses more slowly than a VZV rash and has a centrifugal rather than central distribution that can involve the palms and soles. Lymphadenopathy is a characteristic finding in mpox.⁹ Rickettsialpox is distinguished from VZV primarily by the appearance of brown or black eschar after the original papulovesicular lesions dry out.¹⁰ Atypical hand, foot, and mouth disease can manifest in adults as widespread papulovesicular lesions. This form is associated with coxsackievirus A6 and may require direct fluorescent antibody assay or polymerase chain reaction of keratinocytes to rule out VZV.¹¹

Herpes zoster occurs in older adults with a history of primary VZV.⁶ It manifests as vesicular lesions confined to 1 or 2 adjacent dermatomes vs the diffuse spread of VZV over the entire body. However, HZ can become disseminated in immunocompromised individuals, making it difficult to clinically distinguish from VZV.⁶ Serology can be helpful, as high IgM titers indicate an acute primary VZV infection. Subsequently increased IgG titers steadily wane over time and spike during reactivation.¹²

Dermatology and infectious disease consultations in our cases yielded a preliminary diagnosis through physical examination that was confirmed by biopsy and subsequent laboratory testing, which allowed for a swift response by the infection control team including isolation precautions to control a potential outbreak. Patients with VZV should remain in respiratory isolation until all lesions have crusted over.⁶

Individuals who had face-to-face indoor contact for at least 5 minutes or who shared a living space with an infected individual should be assessed for VZV immunity, which is defined as confirmed prior immunization or infection.^5,13 Lack of VZV immunity requires postexposure prophylaxis—active immunization for the immunocompetent and passive immunization for the immunocompromised.¹³ Ultimately, no additional cases were reported in the community where our patients resided.

Immunocompetent children with primary VZV require supportive care only. Oral antiviral therapy is the treatment of choice for immunocompetent adults or anyone at increased risk for complications, while intravenous antivirals are recommended for the immunocompromised or those with VZV-related complications.¹⁴ A similar approach is used for HZ. Uncomplicated cases are treated with oral antivirals, and complicated cases (eg, HZ ophthalmicus) are treated with intravenous antivirals.¹⁵ Commonly used antivirals include acyclovir, valacyclovir, and famciclovir.¹⁴

Our cases highlight the ongoing risk for varicella outbreaks in unvaccinated or undervaccinated communities. Physician vigilance is necessary, and dermatology plays a particularly important role in swift and accurate detection of VZV, as demonstrated in our cases by the recognition of classic physical examination findings of erythematous and vesicular papules in each of the patients. Because primary VZV infection can result in life-threatening complications including hepatitis, encephalitis, and pancreatitis, prompt identification and initiation of therapy is important.⁶ Similarly, quick notification of public health officials about detected primary VZV cases is vital to containing potential community outbreaks.

To the Editor:

Cases of primary varicella-zoster virus (VZV) are relatively uncommon in the United States since the introduction of the varicella vaccine in 1995, with an overall decline in cases of more than 97%.¹ Prior to the vaccine, 70% of hospitalizations occurred in children; subsequently, hospitalizations among the pediatric population (aged ≤20 years) declined by 97%. Compared to children, adults and immunocompromised patients with VZV infection may present with more severe disease and experience more complications.¹

Most children in the United States are vaccinated against VZV, with 90.3% receiving at least 1 dose by 24 months of age.² However, many countries do not implement universal varicella vaccination for infants.³ As a result, physicians should remember to include primary varicella in the differential when clinically correlated, especially when evaluating patients who have immigrated to the United States or who may be living in unvaccinated communities. We report 2 cases of primary VZV manifesting in adults to remind readers of the salient clinical features of this disease and how dermatologists play a critical role in early and accurate identification of diseases that can have wide-reaching public health implications.

A 26-year-old man with no relevant medical history presented to the emergency department with an itchy and painful rash of 5 days’ duration that began on the trunk and spread to the face, lips, feet, hands, arms, and legs. He also reported shortness of breath, cough, and chills, and he had a temperature of 100.8 °F (38.2 °C). Physical examination revealed numerous erythematous papules and vesiculopustules, some with central umbilication and some with overlying gold crusts (Figure 1).

Later that day, a 47-year-old man with no relevant medical history presented to the same emergency department with a rash along with self-reported fever and sore throat of 3 days’ duration. Physical examination found innumerable erythematous vesicopustules scattered on the face, scalp, neck, trunk, arms, and legs, some with a “dew drop on a rose petal” appearance and some with overlying hemorrhagic crust (Figure 2).

Although infection was of primary concern for the first patient, the presentation of the second patient prompted specific concern for primary VZV infection in both patients, who were placed on airborne and contact isolation precautions.

Skin biopsies from both patients showed acantholytic blisters, hair follicle necrosis, and marked dermal inflammation (Figure 3). Herpetic viral changes were seen in keratinocytes, with steel-grey nuclei, multinucleated keratinocytes, and chromatin margination. An immunostain for VZV was diffusely positive, and VZV antibody IgG was positive (Figure 4).

Upon additional questioning, both patients reported recent exposure to VZV-like illnesses in family members without a history of international travel. Neither of the patients was sure of their vaccination status or prior infection history. Both patients received intravenous acyclovir 10 mg/kg administered every 8 hours. Both patients experienced improvement and were discharged after 3 days on oral valacyclovir (1 g 3 times daily for a 7-day treatment course).

The similar presentation and timing of these 2 VZV cases caused concern for an unidentified community outbreak. The infection control team was notified; additionally, per hospital protocol the state health department was alerted as well as the clinicians and staff of the hospital with a request to be vigilant for further cases.

Despite high vaccination rates in the United States, outbreaks of varicella still occur, particularly among unvaccinated individuals, and a robust and efficient response is necessary to control the spread of such outbreaks.⁴ Many states, including Arkansas where our cases occurred, have laws mandating report of VZV cases to the department of health.⁵ Dermatologists play an important role in reporting cases, aiding in diagnosis through recognition of the physical examination findings, obtaining appropriate biopsy, and recommending additional laboratory testing.

Typical skin manifestations include a pruritic rash of macules, papules, vesicles, and crusted lesions distributed throughout the trunk, face, arms, and legs. Because new lesions appear over several days, they will be in different stages of healing, resulting in the simultaneous presence of papules, vesicles, and crusted lesions.⁶ This unique characteristic helps distinguish VZV from other skin diseases such as smallpox or mpox (monkeypox), which generally show lesions in similar stages of evolution.

Biopsy also can aid in identification. Viruses in the herpes family reveal similar histopathologic characteristics, including acantholysis and vesicle formation, intranuclear inclusions with margination of chromatin, multinucleation, and nuclear molding.⁷ Immunohistochemistry can be used to differentiate VZV from herpes simplex virus; however, neither microscopic examination nor immunohistochemistry distinguish primary VZV infection from herpes zoster (HZ).⁸

The mpox rash progresses more slowly than a VZV rash and has a centrifugal rather than central distribution that can involve the palms and soles. Lymphadenopathy is a characteristic finding in mpox.⁹ Rickettsialpox is distinguished from VZV primarily by the appearance of brown or black eschar after the original papulovesicular lesions dry out.¹⁰ Atypical hand, foot, and mouth disease can manifest in adults as widespread papulovesicular lesions. This form is associated with coxsackievirus A6 and may require direct fluorescent antibody assay or polymerase chain reaction of keratinocytes to rule out VZV.¹¹

Herpes zoster occurs in older adults with a history of primary VZV.⁶ It manifests as vesicular lesions confined to 1 or 2 adjacent dermatomes vs the diffuse spread of VZV over the entire body. However, HZ can become disseminated in immunocompromised individuals, making it difficult to clinically distinguish from VZV.⁶ Serology can be helpful, as high IgM titers indicate an acute primary VZV infection. Subsequently increased IgG titers steadily wane over time and spike during reactivation.¹²

Dermatology and infectious disease consultations in our cases yielded a preliminary diagnosis through physical examination that was confirmed by biopsy and subsequent laboratory testing, which allowed for a swift response by the infection control team including isolation precautions to control a potential outbreak. Patients with VZV should remain in respiratory isolation until all lesions have crusted over.⁶

Individuals who had face-to-face indoor contact for at least 5 minutes or who shared a living space with an infected individual should be assessed for VZV immunity, which is defined as confirmed prior immunization or infection.^5,13 Lack of VZV immunity requires postexposure prophylaxis—active immunization for the immunocompetent and passive immunization for the immunocompromised.¹³ Ultimately, no additional cases were reported in the community where our patients resided.

Immunocompetent children with primary VZV require supportive care only. Oral antiviral therapy is the treatment of choice for immunocompetent adults or anyone at increased risk for complications, while intravenous antivirals are recommended for the immunocompromised or those with VZV-related complications.¹⁴ A similar approach is used for HZ. Uncomplicated cases are treated with oral antivirals, and complicated cases (eg, HZ ophthalmicus) are treated with intravenous antivirals.¹⁵ Commonly used antivirals include acyclovir, valacyclovir, and famciclovir.¹⁴

Our cases highlight the ongoing risk for varicella outbreaks in unvaccinated or undervaccinated communities. Physician vigilance is necessary, and dermatology plays a particularly important role in swift and accurate detection of VZV, as demonstrated in our cases by the recognition of classic physical examination findings of erythematous and vesicular papules in each of the patients. Because primary VZV infection can result in life-threatening complications including hepatitis, encephalitis, and pancreatitis, prompt identification and initiation of therapy is important.⁶ Similarly, quick notification of public health officials about detected primary VZV cases is vital to containing potential community outbreaks.

To the Editor:

Cases of primary varicella-zoster virus (VZV) are relatively uncommon in the United States since the introduction of the varicella vaccine in 1995, with an overall decline in cases of more than 97%.¹ Prior to the vaccine, 70% of hospitalizations occurred in children; subsequently, hospitalizations among the pediatric population (aged ≤20 years) declined by 97%. Compared to children, adults and immunocompromised patients with VZV infection may present with more severe disease and experience more complications.¹

Most children in the United States are vaccinated against VZV, with 90.3% receiving at least 1 dose by 24 months of age.² However, many countries do not implement universal varicella vaccination for infants.³ As a result, physicians should remember to include primary varicella in the differential when clinically correlated, especially when evaluating patients who have immigrated to the United States or who may be living in unvaccinated communities. We report 2 cases of primary VZV manifesting in adults to remind readers of the salient clinical features of this disease and how dermatologists play a critical role in early and accurate identification of diseases that can have wide-reaching public health implications.

A 26-year-old man with no relevant medical history presented to the emergency department with an itchy and painful rash of 5 days’ duration that began on the trunk and spread to the face, lips, feet, hands, arms, and legs. He also reported shortness of breath, cough, and chills, and he had a temperature of 100.8 °F (38.2 °C). Physical examination revealed numerous erythematous papules and vesiculopustules, some with central umbilication and some with overlying gold crusts (Figure 1).

Later that day, a 47-year-old man with no relevant medical history presented to the same emergency department with a rash along with self-reported fever and sore throat of 3 days’ duration. Physical examination found innumerable erythematous vesicopustules scattered on the face, scalp, neck, trunk, arms, and legs, some with a “dew drop on a rose petal” appearance and some with overlying hemorrhagic crust (Figure 2).

Although infection was of primary concern for the first patient, the presentation of the second patient prompted specific concern for primary VZV infection in both patients, who were placed on airborne and contact isolation precautions.

Skin biopsies from both patients showed acantholytic blisters, hair follicle necrosis, and marked dermal inflammation (Figure 3). Herpetic viral changes were seen in keratinocytes, with steel-grey nuclei, multinucleated keratinocytes, and chromatin margination. An immunostain for VZV was diffusely positive, and VZV antibody IgG was positive (Figure 4).

Upon additional questioning, both patients reported recent exposure to VZV-like illnesses in family members without a history of international travel. Neither of the patients was sure of their vaccination status or prior infection history. Both patients received intravenous acyclovir 10 mg/kg administered every 8 hours. Both patients experienced improvement and were discharged after 3 days on oral valacyclovir (1 g 3 times daily for a 7-day treatment course).

The similar presentation and timing of these 2 VZV cases caused concern for an unidentified community outbreak. The infection control team was notified; additionally, per hospital protocol the state health department was alerted as well as the clinicians and staff of the hospital with a request to be vigilant for further cases.

Despite high vaccination rates in the United States, outbreaks of varicella still occur, particularly among unvaccinated individuals, and a robust and efficient response is necessary to control the spread of such outbreaks.⁴ Many states, including Arkansas where our cases occurred, have laws mandating report of VZV cases to the department of health.⁵ Dermatologists play an important role in reporting cases, aiding in diagnosis through recognition of the physical examination findings, obtaining appropriate biopsy, and recommending additional laboratory testing.

Typical skin manifestations include a pruritic rash of macules, papules, vesicles, and crusted lesions distributed throughout the trunk, face, arms, and legs. Because new lesions appear over several days, they will be in different stages of healing, resulting in the simultaneous presence of papules, vesicles, and crusted lesions.⁶ This unique characteristic helps distinguish VZV from other skin diseases such as smallpox or mpox (monkeypox), which generally show lesions in similar stages of evolution.

Biopsy also can aid in identification. Viruses in the herpes family reveal similar histopathologic characteristics, including acantholysis and vesicle formation, intranuclear inclusions with margination of chromatin, multinucleation, and nuclear molding.⁷ Immunohistochemistry can be used to differentiate VZV from herpes simplex virus; however, neither microscopic examination nor immunohistochemistry distinguish primary VZV infection from herpes zoster (HZ).⁸

The mpox rash progresses more slowly than a VZV rash and has a centrifugal rather than central distribution that can involve the palms and soles. Lymphadenopathy is a characteristic finding in mpox.⁹ Rickettsialpox is distinguished from VZV primarily by the appearance of brown or black eschar after the original papulovesicular lesions dry out.¹⁰ Atypical hand, foot, and mouth disease can manifest in adults as widespread papulovesicular lesions. This form is associated with coxsackievirus A6 and may require direct fluorescent antibody assay or polymerase chain reaction of keratinocytes to rule out VZV.¹¹

Herpes zoster occurs in older adults with a history of primary VZV.⁶ It manifests as vesicular lesions confined to 1 or 2 adjacent dermatomes vs the diffuse spread of VZV over the entire body. However, HZ can become disseminated in immunocompromised individuals, making it difficult to clinically distinguish from VZV.⁶ Serology can be helpful, as high IgM titers indicate an acute primary VZV infection. Subsequently increased IgG titers steadily wane over time and spike during reactivation.¹²

Dermatology and infectious disease consultations in our cases yielded a preliminary diagnosis through physical examination that was confirmed by biopsy and subsequent laboratory testing, which allowed for a swift response by the infection control team including isolation precautions to control a potential outbreak. Patients with VZV should remain in respiratory isolation until all lesions have crusted over.⁶

Individuals who had face-to-face indoor contact for at least 5 minutes or who shared a living space with an infected individual should be assessed for VZV immunity, which is defined as confirmed prior immunization or infection.^5,13 Lack of VZV immunity requires postexposure prophylaxis—active immunization for the immunocompetent and passive immunization for the immunocompromised.¹³ Ultimately, no additional cases were reported in the community where our patients resided.

Immunocompetent children with primary VZV require supportive care only. Oral antiviral therapy is the treatment of choice for immunocompetent adults or anyone at increased risk for complications, while intravenous antivirals are recommended for the immunocompromised or those with VZV-related complications.¹⁴ A similar approach is used for HZ. Uncomplicated cases are treated with oral antivirals, and complicated cases (eg, HZ ophthalmicus) are treated with intravenous antivirals.¹⁵ Commonly used antivirals include acyclovir, valacyclovir, and famciclovir.¹⁴

Our cases highlight the ongoing risk for varicella outbreaks in unvaccinated or undervaccinated communities. Physician vigilance is necessary, and dermatology plays a particularly important role in swift and accurate detection of VZV, as demonstrated in our cases by the recognition of classic physical examination findings of erythematous and vesicular papules in each of the patients. Because primary VZV infection can result in life-threatening complications including hepatitis, encephalitis, and pancreatitis, prompt identification and initiation of therapy is important.⁶ Similarly, quick notification of public health officials about detected primary VZV cases is vital to containing potential community outbreaks.

To the Editor:

A 73-year-old man was admitted to the hospital with progressive abdominal and hip pain of several weeks’ duration that was accompanied by unilateral swelling of the left leg. He had a medical history of hypertension, hyperlipidemia, and prediabetes. Computed tomography (CT) showed extensive intra-abdominal, retroperitoneal, and pelvic lymphadenopathy in addition to poorly defined hepatic lesions.

A CT-guided core biopsy of a left inguinal lymph node showed Burkitt lymphoma. Fluorescence in situ hybridization was positive for oncogene c-MYC rearrangement on chromosome 8q24 and negative for B-cell lymphoma 2 (BCL2) and B-cell lymphoma 6 (BCL6) gene rearrangements. Flow cytometry demonstrated an aberrant population of κ light chain-restricted CD5⁻CD10⁺ B lymphocytes.

The patient’s overall disease burden was consistent with stage IV Burkitt lymphoma. R-miniCHOP chemotherapy—rituximab plus a reduced dose of cyclophosphamide, doxorubicin, vincristine sulfate, and prednisone—was initiated. Approximately 2 weeks after chemotherapy was initiated, the patient developed a firm erythematous eruption on the left hip (Figure 1A). His regimen was then switched to R-EPOCH—rituximab, etoposide phosphate, prednisone, vincristine sulfate, cyclophosphamide, and doxorubicin—at the time of discharge, and he was referred to dermatology due to an initial concern of an adverse reaction to R-EPOCH chemotherapy. The patient denied any pain, pruritus, or irritation. Physical examination showed multifocal, subcutaneous, indurated, erythematous and violaceous nodules without epidermal changes. Some nodules on the lateral aspect of the hip coalesced to form firm plaques.

A punch biopsy specimen showed markedly atypical lymphocytes with enlarged nuclei and scant cytoplasm present throughout the dermis (Figures 2A and 2B). Numerous apoptotic cells and cellular debris were seen. Immunohistochemical staining demonstrated that the lymphocytic infiltrate comprised CD79a⁺ B cells that were positive for Bcl-6 and CD10 and negative for Bcl-2 (Figures 2C and 2D). There also was diminished focal expression of CD20. Ki-67 protein staining was intensely positive and demonstrated a very high proliferative index.

Taken together, these findings were consistent with a diagnosis of cutaneous metastasis of Burkitt lymphoma. The patient’s cutaneous lesions improved after continued aggressive chemotherapy. At follow-up 2 weeks after biopsy, he was receiving his second round of R-EPOCH chemotherapy with appreciable regression of skin lesions (Figure 1B). However, he then developed right-side double vision, ptosis, and right-side facial paresthesia. Although magnetic resonance imaging of the brain and lumbar puncture did not show evidence of central nervous system involvement, the chemotherapy regimen was switched to dose-adjusted CVAD-R—hypercyclophosphamide, vincristine, doxorubicin hydrochloride, and dexamethasone plus rituximab—for empiric treatment of central nervous system disease. Although treatment was complicated by sepsis with extended-spectrum β-lactamase-producing Enterobacter cloacae, Burkitt lymphoma was found to be in remission after 3 cycles of CVAD-R and 5 months of chemotherapy.

Burkitt lymphoma is a B-cell non-Hodgkin malignancy caused by translocation of chromosome 8 and chromosome 14, leading to overexpression of c-MYC and subsequent hyperproliferation of B lymphocytes.^1,2 The disease is divided into 3 major categories: sporadic, endemic, and immunodeficiency related.³ The endemic variant is the most prevalent subtype in Africa and is associated with Plasmodium falciparum malaria; the sporadic variant is the most common subtype in the rest of the world.⁴

Burkitt lymphoma is highly aggressive and is characterized by unusually high rates of mitosis and apoptosis that result in abundant cellular debris and a distinctive starry-sky pattern on histopathology.^5,6 Extranodal metastasis is common,⁷ but cutaneous involvement is exceedingly rare, with only a few cases having been reported.^8-14 Cutaneous metastasis of Burkitt lymphoma often is associated with a high overall disease burden and poor prognosis.^8,11

Immunodeficiency-related Burkitt lymphoma is particularly aggressive. Notably, 3 of 7 (42.9%) reported cases of cutaneous Burkitt lymphoma occurred in HIV-positive patients.^11,13 In one case, cutaneous involvement was the first sign of relapsed disease that had been in remission.¹²

Although c-MYC rearrangement is required to make a diagnosis of Burkitt lymphoma, the disease also is present in a minority of cases of diffuse large B-cell lymphoma (DLBCL)(6%).¹⁵ Although DLBCL typically can be differentiated from Burkitt lymphoma by the large nuclear size and characteristic vesicular nuclei of B cells, few cases of DLBCL with c-MYC rearrangement histologically mimic Burkitt lymphoma. However, key features such as immunohistochemical staining for Bcl-2 and CD10 can be used to distinguish these 2 entities.¹⁶ Bcl-2 negativity and CD10 positivity, as seen in our patient, is considered more characteristic of Burkitt lymphoma. This staining pattern in combination with a high Ki-67 fraction (>95%) and the presence of monomorphic medium-sized cells is more consistent with a diagnosis of Burkitt lymphoma than of DLBCL.¹⁷

Earlier case reports have documented that cutaneous lesions of Burkitt lymphoma can occur in a variety of ways. Hematogenous spread is the likely route of metastasis for lesions distant to the primary site or those that have widespread distribution.¹⁸ Alternatively, other reports have suggested that cutaneous metastases can occur from local invasion and subcutaneous extension of malignant cells after a surgical procedure.^10,19 For example, cutaneous Burkitt lymphoma has been reported in the setting of celioscopy, occurring directly at the surgical site.¹⁹ In our patient, we believe that the route of metastatic spread likely was through subcutaneous invasion secondary to CT-guided core biopsy, which was supported by the observation that the onset of cutaneous manifestations was temporally related to the procedure and that the lesions occurred on the skin directly overlying the biopsy site.

In conclusion, we describe an exceedingly rare presentation of cutaneous Burkitt lymphoma in which a surgical procedure likely served as an inciting event that triggered seeding of malignant cells to the skin. Cutaneous spread of Burkitt lymphoma is infrequently reported; all such reports that provide long-term follow-up data have described it in association with high disease burden and often a lethal outcome.^8,11,12 Our patient had complete resolution of cutaneous lesions with chemotherapy. It is unclear if the presence of cutaneous lesions can serve as a prognostic indicator and requires further investigation. However, our case provides preliminary evidence to suggest that cutaneous metastases do not always represent aggressive disease and that cutaneous lesions may respond well to chemotherapy.

To the Editor:

A 73-year-old man was admitted to the hospital with progressive abdominal and hip pain of several weeks’ duration that was accompanied by unilateral swelling of the left leg. He had a medical history of hypertension, hyperlipidemia, and prediabetes. Computed tomography (CT) showed extensive intra-abdominal, retroperitoneal, and pelvic lymphadenopathy in addition to poorly defined hepatic lesions.

A CT-guided core biopsy of a left inguinal lymph node showed Burkitt lymphoma. Fluorescence in situ hybridization was positive for oncogene c-MYC rearrangement on chromosome 8q24 and negative for B-cell lymphoma 2 (BCL2) and B-cell lymphoma 6 (BCL6) gene rearrangements. Flow cytometry demonstrated an aberrant population of κ light chain-restricted CD5⁻CD10⁺ B lymphocytes.

The patient’s overall disease burden was consistent with stage IV Burkitt lymphoma. R-miniCHOP chemotherapy—rituximab plus a reduced dose of cyclophosphamide, doxorubicin, vincristine sulfate, and prednisone—was initiated. Approximately 2 weeks after chemotherapy was initiated, the patient developed a firm erythematous eruption on the left hip (Figure 1A). His regimen was then switched to R-EPOCH—rituximab, etoposide phosphate, prednisone, vincristine sulfate, cyclophosphamide, and doxorubicin—at the time of discharge, and he was referred to dermatology due to an initial concern of an adverse reaction to R-EPOCH chemotherapy. The patient denied any pain, pruritus, or irritation. Physical examination showed multifocal, subcutaneous, indurated, erythematous and violaceous nodules without epidermal changes. Some nodules on the lateral aspect of the hip coalesced to form firm plaques.

A punch biopsy specimen showed markedly atypical lymphocytes with enlarged nuclei and scant cytoplasm present throughout the dermis (Figures 2A and 2B). Numerous apoptotic cells and cellular debris were seen. Immunohistochemical staining demonstrated that the lymphocytic infiltrate comprised CD79a⁺ B cells that were positive for Bcl-6 and CD10 and negative for Bcl-2 (Figures 2C and 2D). There also was diminished focal expression of CD20. Ki-67 protein staining was intensely positive and demonstrated a very high proliferative index.

Taken together, these findings were consistent with a diagnosis of cutaneous metastasis of Burkitt lymphoma. The patient’s cutaneous lesions improved after continued aggressive chemotherapy. At follow-up 2 weeks after biopsy, he was receiving his second round of R-EPOCH chemotherapy with appreciable regression of skin lesions (Figure 1B). However, he then developed right-side double vision, ptosis, and right-side facial paresthesia. Although magnetic resonance imaging of the brain and lumbar puncture did not show evidence of central nervous system involvement, the chemotherapy regimen was switched to dose-adjusted CVAD-R—hypercyclophosphamide, vincristine, doxorubicin hydrochloride, and dexamethasone plus rituximab—for empiric treatment of central nervous system disease. Although treatment was complicated by sepsis with extended-spectrum β-lactamase-producing Enterobacter cloacae, Burkitt lymphoma was found to be in remission after 3 cycles of CVAD-R and 5 months of chemotherapy.

Burkitt lymphoma is a B-cell non-Hodgkin malignancy caused by translocation of chromosome 8 and chromosome 14, leading to overexpression of c-MYC and subsequent hyperproliferation of B lymphocytes.^1,2 The disease is divided into 3 major categories: sporadic, endemic, and immunodeficiency related.³ The endemic variant is the most prevalent subtype in Africa and is associated with Plasmodium falciparum malaria; the sporadic variant is the most common subtype in the rest of the world.⁴

Burkitt lymphoma is highly aggressive and is characterized by unusually high rates of mitosis and apoptosis that result in abundant cellular debris and a distinctive starry-sky pattern on histopathology.^5,6 Extranodal metastasis is common,⁷ but cutaneous involvement is exceedingly rare, with only a few cases having been reported.^8-14 Cutaneous metastasis of Burkitt lymphoma often is associated with a high overall disease burden and poor prognosis.^8,11

Immunodeficiency-related Burkitt lymphoma is particularly aggressive. Notably, 3 of 7 (42.9%) reported cases of cutaneous Burkitt lymphoma occurred in HIV-positive patients.^11,13 In one case, cutaneous involvement was the first sign of relapsed disease that had been in remission.¹²

Although c-MYC rearrangement is required to make a diagnosis of Burkitt lymphoma, the disease also is present in a minority of cases of diffuse large B-cell lymphoma (DLBCL)(6%).¹⁵ Although DLBCL typically can be differentiated from Burkitt lymphoma by the large nuclear size and characteristic vesicular nuclei of B cells, few cases of DLBCL with c-MYC rearrangement histologically mimic Burkitt lymphoma. However, key features such as immunohistochemical staining for Bcl-2 and CD10 can be used to distinguish these 2 entities.¹⁶ Bcl-2 negativity and CD10 positivity, as seen in our patient, is considered more characteristic of Burkitt lymphoma. This staining pattern in combination with a high Ki-67 fraction (>95%) and the presence of monomorphic medium-sized cells is more consistent with a diagnosis of Burkitt lymphoma than of DLBCL.¹⁷

Earlier case reports have documented that cutaneous lesions of Burkitt lymphoma can occur in a variety of ways. Hematogenous spread is the likely route of metastasis for lesions distant to the primary site or those that have widespread distribution.¹⁸ Alternatively, other reports have suggested that cutaneous metastases can occur from local invasion and subcutaneous extension of malignant cells after a surgical procedure.^10,19 For example, cutaneous Burkitt lymphoma has been reported in the setting of celioscopy, occurring directly at the surgical site.¹⁹ In our patient, we believe that the route of metastatic spread likely was through subcutaneous invasion secondary to CT-guided core biopsy, which was supported by the observation that the onset of cutaneous manifestations was temporally related to the procedure and that the lesions occurred on the skin directly overlying the biopsy site.

In conclusion, we describe an exceedingly rare presentation of cutaneous Burkitt lymphoma in which a surgical procedure likely served as an inciting event that triggered seeding of malignant cells to the skin. Cutaneous spread of Burkitt lymphoma is infrequently reported; all such reports that provide long-term follow-up data have described it in association with high disease burden and often a lethal outcome.^8,11,12 Our patient had complete resolution of cutaneous lesions with chemotherapy. It is unclear if the presence of cutaneous lesions can serve as a prognostic indicator and requires further investigation. However, our case provides preliminary evidence to suggest that cutaneous metastases do not always represent aggressive disease and that cutaneous lesions may respond well to chemotherapy.

To the Editor:

A 73-year-old man was admitted to the hospital with progressive abdominal and hip pain of several weeks’ duration that was accompanied by unilateral swelling of the left leg. He had a medical history of hypertension, hyperlipidemia, and prediabetes. Computed tomography (CT) showed extensive intra-abdominal, retroperitoneal, and pelvic lymphadenopathy in addition to poorly defined hepatic lesions.

A CT-guided core biopsy of a left inguinal lymph node showed Burkitt lymphoma. Fluorescence in situ hybridization was positive for oncogene c-MYC rearrangement on chromosome 8q24 and negative for B-cell lymphoma 2 (BCL2) and B-cell lymphoma 6 (BCL6) gene rearrangements. Flow cytometry demonstrated an aberrant population of κ light chain-restricted CD5⁻CD10⁺ B lymphocytes.

The patient’s overall disease burden was consistent with stage IV Burkitt lymphoma. R-miniCHOP chemotherapy—rituximab plus a reduced dose of cyclophosphamide, doxorubicin, vincristine sulfate, and prednisone—was initiated. Approximately 2 weeks after chemotherapy was initiated, the patient developed a firm erythematous eruption on the left hip (Figure 1A). His regimen was then switched to R-EPOCH—rituximab, etoposide phosphate, prednisone, vincristine sulfate, cyclophosphamide, and doxorubicin—at the time of discharge, and he was referred to dermatology due to an initial concern of an adverse reaction to R-EPOCH chemotherapy. The patient denied any pain, pruritus, or irritation. Physical examination showed multifocal, subcutaneous, indurated, erythematous and violaceous nodules without epidermal changes. Some nodules on the lateral aspect of the hip coalesced to form firm plaques.

A punch biopsy specimen showed markedly atypical lymphocytes with enlarged nuclei and scant cytoplasm present throughout the dermis (Figures 2A and 2B). Numerous apoptotic cells and cellular debris were seen. Immunohistochemical staining demonstrated that the lymphocytic infiltrate comprised CD79a⁺ B cells that were positive for Bcl-6 and CD10 and negative for Bcl-2 (Figures 2C and 2D). There also was diminished focal expression of CD20. Ki-67 protein staining was intensely positive and demonstrated a very high proliferative index.

Taken together, these findings were consistent with a diagnosis of cutaneous metastasis of Burkitt lymphoma. The patient’s cutaneous lesions improved after continued aggressive chemotherapy. At follow-up 2 weeks after biopsy, he was receiving his second round of R-EPOCH chemotherapy with appreciable regression of skin lesions (Figure 1B). However, he then developed right-side double vision, ptosis, and right-side facial paresthesia. Although magnetic resonance imaging of the brain and lumbar puncture did not show evidence of central nervous system involvement, the chemotherapy regimen was switched to dose-adjusted CVAD-R—hypercyclophosphamide, vincristine, doxorubicin hydrochloride, and dexamethasone plus rituximab—for empiric treatment of central nervous system disease. Although treatment was complicated by sepsis with extended-spectrum β-lactamase-producing Enterobacter cloacae, Burkitt lymphoma was found to be in remission after 3 cycles of CVAD-R and 5 months of chemotherapy.

Burkitt lymphoma is a B-cell non-Hodgkin malignancy caused by translocation of chromosome 8 and chromosome 14, leading to overexpression of c-MYC and subsequent hyperproliferation of B lymphocytes.^1,2 The disease is divided into 3 major categories: sporadic, endemic, and immunodeficiency related.³ The endemic variant is the most prevalent subtype in Africa and is associated with Plasmodium falciparum malaria; the sporadic variant is the most common subtype in the rest of the world.⁴

Burkitt lymphoma is highly aggressive and is characterized by unusually high rates of mitosis and apoptosis that result in abundant cellular debris and a distinctive starry-sky pattern on histopathology.^5,6 Extranodal metastasis is common,⁷ but cutaneous involvement is exceedingly rare, with only a few cases having been reported.^8-14 Cutaneous metastasis of Burkitt lymphoma often is associated with a high overall disease burden and poor prognosis.^8,11

Immunodeficiency-related Burkitt lymphoma is particularly aggressive. Notably, 3 of 7 (42.9%) reported cases of cutaneous Burkitt lymphoma occurred in HIV-positive patients.^11,13 In one case, cutaneous involvement was the first sign of relapsed disease that had been in remission.¹²

Although c-MYC rearrangement is required to make a diagnosis of Burkitt lymphoma, the disease also is present in a minority of cases of diffuse large B-cell lymphoma (DLBCL)(6%).¹⁵ Although DLBCL typically can be differentiated from Burkitt lymphoma by the large nuclear size and characteristic vesicular nuclei of B cells, few cases of DLBCL with c-MYC rearrangement histologically mimic Burkitt lymphoma. However, key features such as immunohistochemical staining for Bcl-2 and CD10 can be used to distinguish these 2 entities.¹⁶ Bcl-2 negativity and CD10 positivity, as seen in our patient, is considered more characteristic of Burkitt lymphoma. This staining pattern in combination with a high Ki-67 fraction (>95%) and the presence of monomorphic medium-sized cells is more consistent with a diagnosis of Burkitt lymphoma than of DLBCL.¹⁷

Earlier case reports have documented that cutaneous lesions of Burkitt lymphoma can occur in a variety of ways. Hematogenous spread is the likely route of metastasis for lesions distant to the primary site or those that have widespread distribution.¹⁸ Alternatively, other reports have suggested that cutaneous metastases can occur from local invasion and subcutaneous extension of malignant cells after a surgical procedure.^10,19 For example, cutaneous Burkitt lymphoma has been reported in the setting of celioscopy, occurring directly at the surgical site.¹⁹ In our patient, we believe that the route of metastatic spread likely was through subcutaneous invasion secondary to CT-guided core biopsy, which was supported by the observation that the onset of cutaneous manifestations was temporally related to the procedure and that the lesions occurred on the skin directly overlying the biopsy site.

In conclusion, we describe an exceedingly rare presentation of cutaneous Burkitt lymphoma in which a surgical procedure likely served as an inciting event that triggered seeding of malignant cells to the skin. Cutaneous spread of Burkitt lymphoma is infrequently reported; all such reports that provide long-term follow-up data have described it in association with high disease burden and often a lethal outcome.^8,11,12 Our patient had complete resolution of cutaneous lesions with chemotherapy. It is unclear if the presence of cutaneous lesions can serve as a prognostic indicator and requires further investigation. However, our case provides preliminary evidence to suggest that cutaneous metastases do not always represent aggressive disease and that cutaneous lesions may respond well to chemotherapy.

To the Editor:

Cellulitis is the most common reason for skin-related hospital admissions.¹ Despite its frequency, it is suspected that many cases of cellulitis are misdiagnosed as other etiologies presenting with similar symptoms such as a ruptured Baker cyst. These cysts are located behind the knee and can present with calf pain, peripheral edema, and erythema when ruptured. Symptoms of a ruptured Baker cyst can be indistinguishable from cellulitis as well as deep vein thrombosis (DVT), both manifesting with lower extremity pain, swelling, and erythema, making diagnosis challenging.² The hemorrhagic crescent sign—a crescent of ecchymosis distal to the medial malleolus and on the foot that results from synovial injury or rupture—can be a useful diagnostic tool to differentiate between the causes of acute swelling and pain of the leg.² When observed, the hemorrhagic crescent sign supports testing for synovial pathology at the knee.

A 63-year-old man presented to an outside hospital for evaluation of a fever (temperature, 101 °F [38.3 °C]), as well as pain, edema, and erythema of the right lower leg of 2 days’ duration. He had a history of leg cellulitis, gout, diabetes mellitus, lymphedema, and peripheral neuropathy. On admission, he was found to have elevated C-reactive protein (45 mg/L [reference range, <8 mg/L]) and mild leukocytosis (13,500 cells/μL [reference range, 4500–11,000 cells/μL]). A venous duplex scan did not demonstrate signs of thrombosis. Antibiotic therapy was started for suspected cellulitis including levofloxacin, piperacillin-tazobactam, and linezolid. Despite broad-spectrum antibiotic coverage, the patient continued to be febrile and experienced progressive erythema and swelling of the right lower leg, at which point he was transferred to our institution. A new antibiotic regimen of vancomycin, cefepime, and clindamycin was started and showed no improvement, after which dermatology was consulted.

Physical examination revealed unilateral edema and calor of the right lower leg with a demarcated erythematous rash extending to the level of the knee. Furthermore, a hemorrhagic crescent sign was present below the right medial malleolus (Figure). The popliteal fossa was supple, though the patient was adamant that he had a Baker cyst. Punch biopsies demonstrated epidermal spongiosis and extensive edema with perivascular inflammation. No organisms were found by stain and culture. Ultrasound records confirmed a Baker cyst present at least 4 months prior; however, a repeat ultrasound showed resolution. A diagnosis of pseudocellulitis secondary to Baker cyst rupture was made, and corticosteroids were started, resulting in marked reduction in erythema and edema of the lower leg and hospital discharge.

This case highlights the importance of early involvement of dermatology when cellulitis is suspected. A study of 635 patients in the United Kingdom referred to dermatology for lower limb cellulitis found that 210 (33%) patients did not have cellulitis and only 18 (3%) required hospital admission.³ Dermatology consultations have been shown to benefit patients with inflammatory skin disease by decreasing length of stay and reducing readmissions.⁴

Our patient had several risk factors for cellulitis, including obesity, lymphedema, and chronic kidney disease, in addition to having fevers and unilateral involvement. However, failure of symptoms to improve with broad-spectrum antibiotics made a diagnosis of cellulitis less likely. In this case, a severe immune response to the ruptured Baker cyst mimicked the presentation of cellulitis.

Ruptured Baker cysts have been reported to cause acute leg swelling, mimicking the symptoms of cellulitis or DVT.^2,5 The presence of a hemorrhagic crescent sign can be a useful diagnostic tool, as in our patient, because it has been reported as an indication of synovial injury or rupture, supporting the exclusion of cellulitis or DVT when it is observed.⁶ Prior reports have observed ecchymosis on the foot in as little as 1 day after the onset of calf swelling and at the lateral malleolus 3 days after the onset of calf swelling.⁵

Following suspicion of a ruptured Baker cyst causing pseudocellulitis, an ultrasound can be used to confirm the diagnosis. Ultrasonography shows a large hypoechoic space behind the calf muscles, which is pathognomonic of a ruptured Baker cyst.⁷

In conclusion, when a hemorrhagic crescent sign is observed, one should be suspicious for a ruptured Baker cyst or other synovial pathology as an etiology of pseudocellulitis. Early recognition of the hemorrhagic crescent sign can help rule out cellulitis and DVT, thereby reducing the amount of intravenous antibiotic prescribed, decreasing the length of hospital stay, and reducing readmission.

To the Editor:

Cellulitis is the most common reason for skin-related hospital admissions.¹ Despite its frequency, it is suspected that many cases of cellulitis are misdiagnosed as other etiologies presenting with similar symptoms such as a ruptured Baker cyst. These cysts are located behind the knee and can present with calf pain, peripheral edema, and erythema when ruptured. Symptoms of a ruptured Baker cyst can be indistinguishable from cellulitis as well as deep vein thrombosis (DVT), both manifesting with lower extremity pain, swelling, and erythema, making diagnosis challenging.² The hemorrhagic crescent sign—a crescent of ecchymosis distal to the medial malleolus and on the foot that results from synovial injury or rupture—can be a useful diagnostic tool to differentiate between the causes of acute swelling and pain of the leg.² When observed, the hemorrhagic crescent sign supports testing for synovial pathology at the knee.

A 63-year-old man presented to an outside hospital for evaluation of a fever (temperature, 101 °F [38.3 °C]), as well as pain, edema, and erythema of the right lower leg of 2 days’ duration. He had a history of leg cellulitis, gout, diabetes mellitus, lymphedema, and peripheral neuropathy. On admission, he was found to have elevated C-reactive protein (45 mg/L [reference range, <8 mg/L]) and mild leukocytosis (13,500 cells/μL [reference range, 4500–11,000 cells/μL]). A venous duplex scan did not demonstrate signs of thrombosis. Antibiotic therapy was started for suspected cellulitis including levofloxacin, piperacillin-tazobactam, and linezolid. Despite broad-spectrum antibiotic coverage, the patient continued to be febrile and experienced progressive erythema and swelling of the right lower leg, at which point he was transferred to our institution. A new antibiotic regimen of vancomycin, cefepime, and clindamycin was started and showed no improvement, after which dermatology was consulted.

Physical examination revealed unilateral edema and calor of the right lower leg with a demarcated erythematous rash extending to the level of the knee. Furthermore, a hemorrhagic crescent sign was present below the right medial malleolus (Figure). The popliteal fossa was supple, though the patient was adamant that he had a Baker cyst. Punch biopsies demonstrated epidermal spongiosis and extensive edema with perivascular inflammation. No organisms were found by stain and culture. Ultrasound records confirmed a Baker cyst present at least 4 months prior; however, a repeat ultrasound showed resolution. A diagnosis of pseudocellulitis secondary to Baker cyst rupture was made, and corticosteroids were started, resulting in marked reduction in erythema and edema of the lower leg and hospital discharge.

This case highlights the importance of early involvement of dermatology when cellulitis is suspected. A study of 635 patients in the United Kingdom referred to dermatology for lower limb cellulitis found that 210 (33%) patients did not have cellulitis and only 18 (3%) required hospital admission.³ Dermatology consultations have been shown to benefit patients with inflammatory skin disease by decreasing length of stay and reducing readmissions.⁴

Our patient had several risk factors for cellulitis, including obesity, lymphedema, and chronic kidney disease, in addition to having fevers and unilateral involvement. However, failure of symptoms to improve with broad-spectrum antibiotics made a diagnosis of cellulitis less likely. In this case, a severe immune response to the ruptured Baker cyst mimicked the presentation of cellulitis.

Ruptured Baker cysts have been reported to cause acute leg swelling, mimicking the symptoms of cellulitis or DVT.^2,5 The presence of a hemorrhagic crescent sign can be a useful diagnostic tool, as in our patient, because it has been reported as an indication of synovial injury or rupture, supporting the exclusion of cellulitis or DVT when it is observed.⁶ Prior reports have observed ecchymosis on the foot in as little as 1 day after the onset of calf swelling and at the lateral malleolus 3 days after the onset of calf swelling.⁵

Following suspicion of a ruptured Baker cyst causing pseudocellulitis, an ultrasound can be used to confirm the diagnosis. Ultrasonography shows a large hypoechoic space behind the calf muscles, which is pathognomonic of a ruptured Baker cyst.⁷

In conclusion, when a hemorrhagic crescent sign is observed, one should be suspicious for a ruptured Baker cyst or other synovial pathology as an etiology of pseudocellulitis. Early recognition of the hemorrhagic crescent sign can help rule out cellulitis and DVT, thereby reducing the amount of intravenous antibiotic prescribed, decreasing the length of hospital stay, and reducing readmission.

To the Editor:

Cellulitis is the most common reason for skin-related hospital admissions.¹ Despite its frequency, it is suspected that many cases of cellulitis are misdiagnosed as other etiologies presenting with similar symptoms such as a ruptured Baker cyst. These cysts are located behind the knee and can present with calf pain, peripheral edema, and erythema when ruptured. Symptoms of a ruptured Baker cyst can be indistinguishable from cellulitis as well as deep vein thrombosis (DVT), both manifesting with lower extremity pain, swelling, and erythema, making diagnosis challenging.² The hemorrhagic crescent sign—a crescent of ecchymosis distal to the medial malleolus and on the foot that results from synovial injury or rupture—can be a useful diagnostic tool to differentiate between the causes of acute swelling and pain of the leg.² When observed, the hemorrhagic crescent sign supports testing for synovial pathology at the knee.

A 63-year-old man presented to an outside hospital for evaluation of a fever (temperature, 101 °F [38.3 °C]), as well as pain, edema, and erythema of the right lower leg of 2 days’ duration. He had a history of leg cellulitis, gout, diabetes mellitus, lymphedema, and peripheral neuropathy. On admission, he was found to have elevated C-reactive protein (45 mg/L [reference range, <8 mg/L]) and mild leukocytosis (13,500 cells/μL [reference range, 4500–11,000 cells/μL]). A venous duplex scan did not demonstrate signs of thrombosis. Antibiotic therapy was started for suspected cellulitis including levofloxacin, piperacillin-tazobactam, and linezolid. Despite broad-spectrum antibiotic coverage, the patient continued to be febrile and experienced progressive erythema and swelling of the right lower leg, at which point he was transferred to our institution. A new antibiotic regimen of vancomycin, cefepime, and clindamycin was started and showed no improvement, after which dermatology was consulted.

Physical examination revealed unilateral edema and calor of the right lower leg with a demarcated erythematous rash extending to the level of the knee. Furthermore, a hemorrhagic crescent sign was present below the right medial malleolus (Figure). The popliteal fossa was supple, though the patient was adamant that he had a Baker cyst. Punch biopsies demonstrated epidermal spongiosis and extensive edema with perivascular inflammation. No organisms were found by stain and culture. Ultrasound records confirmed a Baker cyst present at least 4 months prior; however, a repeat ultrasound showed resolution. A diagnosis of pseudocellulitis secondary to Baker cyst rupture was made, and corticosteroids were started, resulting in marked reduction in erythema and edema of the lower leg and hospital discharge.

This case highlights the importance of early involvement of dermatology when cellulitis is suspected. A study of 635 patients in the United Kingdom referred to dermatology for lower limb cellulitis found that 210 (33%) patients did not have cellulitis and only 18 (3%) required hospital admission.³ Dermatology consultations have been shown to benefit patients with inflammatory skin disease by decreasing length of stay and reducing readmissions.⁴

Our patient had several risk factors for cellulitis, including obesity, lymphedema, and chronic kidney disease, in addition to having fevers and unilateral involvement. However, failure of symptoms to improve with broad-spectrum antibiotics made a diagnosis of cellulitis less likely. In this case, a severe immune response to the ruptured Baker cyst mimicked the presentation of cellulitis.

Ruptured Baker cysts have been reported to cause acute leg swelling, mimicking the symptoms of cellulitis or DVT.^2,5 The presence of a hemorrhagic crescent sign can be a useful diagnostic tool, as in our patient, because it has been reported as an indication of synovial injury or rupture, supporting the exclusion of cellulitis or DVT when it is observed.⁶ Prior reports have observed ecchymosis on the foot in as little as 1 day after the onset of calf swelling and at the lateral malleolus 3 days after the onset of calf swelling.⁵

Following suspicion of a ruptured Baker cyst causing pseudocellulitis, an ultrasound can be used to confirm the diagnosis. Ultrasonography shows a large hypoechoic space behind the calf muscles, which is pathognomonic of a ruptured Baker cyst.⁷

In conclusion, when a hemorrhagic crescent sign is observed, one should be suspicious for a ruptured Baker cyst or other synovial pathology as an etiology of pseudocellulitis. Early recognition of the hemorrhagic crescent sign can help rule out cellulitis and DVT, thereby reducing the amount of intravenous antibiotic prescribed, decreasing the length of hospital stay, and reducing readmission.