Contact Dermatitis

NEW ORLEANS – Suspect an allergic reaction to inactive ingredients in topical corticosteroids when patients do not improve despite usual treatment regimens, a retrospective study suggests.

"An allergy prevalence of 4% for an emulsifier widely used in corticosteroids and personal care products is very important," Brienne Danielle Cressey said at the annual meeting of the American Contact Dermatitis Society.

Ms. Cressey and her associates in the dermatology department at Tufts Medical Center, Boston, reviewed charts of 591 patients who were patch-tested between November 2008 and May 2010. They found that 24 of these patients (4.1%) had positive reactions to a sorbitan emulsifier found in many corticosteroid formulations.

Specifically, 3.9% reacted positively to sorbitan sesquioleate (SSO); 0.85% to sorbitan monooleate (SMO); and 0.7% to both.

"It was thought previously to be an uncommon allergen," said Ms. Cressey, a student at the Maine Medical Center Tufts University School of Medicine (class of 2013) in Portland. In a previous study conducted at Tufts University, researchers found an 8.9% prevalence of sorbitan allergy among 112 dermatitis patients (Dermatitis 2008;19:323-7).

Even though sorbitan allergy was less common in the current study, "we feel it's still an important allergen, with a prevalence greater than 1%." These emulsifiers are not included in the standard patch-testing series, Ms. Cressey said.

Patients were patch-tested using the Tufts Medical Center standard series and a preservative series containing SSO in 20% petrolatum and SMO 5% in petrolatum. Results were read at 48 and 72 hours. The majority were weak reactors: 22 patients were + and 2 were ++. "Our only two patients with 2+ reactions were children with generalized dermatitis," Ms. Cressey said.

Only one patient reacted to any of the four different corticosteroid screening chemicals tested, confirming that these reactions were caused by the sorbitan emulsifiers.

In the positive reaction group, the average duration of contact dermatitis was 43 months, the mean age was 40 years, and 46% were atopic. Dermatitis of the upper extremity and face was the most common.

The sources of sorbitan exposure were personal care products (10 patients), topical corticosteroids (9 patients), and ingestion (5 patients). Ingestion included, for example, sorbitans as a medication ingredient, Ms. Cressey said. "One patient with axillary dermatitis was using deodorant with sorbitol," she added.

The fact that the majority of reactions to SSO were weak raises a question as to whether this emulsifier is a contact or irritant allergen, Ms. Cressey said. Because 27 of 591 patients also were questionable for SSO reactions, "SSO is most likely not an irritant," she said.

In addition to topical corticosteroids, sorbitol-based emulsifiers are found in topical antibiotics, topical antifungals, topical retinoids, and moisturizing creams and lotions (Dermatitis 2008;19:339-41). This publication includes a list of products that commonly contain SSO, sorbitol, and sorbitol derivatives.

Ms. Cressey said that she had no relevant disclosures.

NEW ORLEANS – Suspect an allergic reaction to inactive ingredients in topical corticosteroids when patients do not improve despite usual treatment regimens, a retrospective study suggests.

"An allergy prevalence of 4% for an emulsifier widely used in corticosteroids and personal care products is very important," Brienne Danielle Cressey said at the annual meeting of the American Contact Dermatitis Society.

Ms. Cressey and her associates in the dermatology department at Tufts Medical Center, Boston, reviewed charts of 591 patients who were patch-tested between November 2008 and May 2010. They found that 24 of these patients (4.1%) had positive reactions to a sorbitan emulsifier found in many corticosteroid formulations.

Specifically, 3.9% reacted positively to sorbitan sesquioleate (SSO); 0.85% to sorbitan monooleate (SMO); and 0.7% to both.

"It was thought previously to be an uncommon allergen," said Ms. Cressey, a student at the Maine Medical Center Tufts University School of Medicine (class of 2013) in Portland. In a previous study conducted at Tufts University, researchers found an 8.9% prevalence of sorbitan allergy among 112 dermatitis patients (Dermatitis 2008;19:323-7).

Even though sorbitan allergy was less common in the current study, "we feel it's still an important allergen, with a prevalence greater than 1%." These emulsifiers are not included in the standard patch-testing series, Ms. Cressey said.

Patients were patch-tested using the Tufts Medical Center standard series and a preservative series containing SSO in 20% petrolatum and SMO 5% in petrolatum. Results were read at 48 and 72 hours. The majority were weak reactors: 22 patients were + and 2 were ++. "Our only two patients with 2+ reactions were children with generalized dermatitis," Ms. Cressey said.

Only one patient reacted to any of the four different corticosteroid screening chemicals tested, confirming that these reactions were caused by the sorbitan emulsifiers.

In the positive reaction group, the average duration of contact dermatitis was 43 months, the mean age was 40 years, and 46% were atopic. Dermatitis of the upper extremity and face was the most common.

The sources of sorbitan exposure were personal care products (10 patients), topical corticosteroids (9 patients), and ingestion (5 patients). Ingestion included, for example, sorbitans as a medication ingredient, Ms. Cressey said. "One patient with axillary dermatitis was using deodorant with sorbitol," she added.

The fact that the majority of reactions to SSO were weak raises a question as to whether this emulsifier is a contact or irritant allergen, Ms. Cressey said. Because 27 of 591 patients also were questionable for SSO reactions, "SSO is most likely not an irritant," she said.

In addition to topical corticosteroids, sorbitol-based emulsifiers are found in topical antibiotics, topical antifungals, topical retinoids, and moisturizing creams and lotions (Dermatitis 2008;19:339-41). This publication includes a list of products that commonly contain SSO, sorbitol, and sorbitol derivatives.

Ms. Cressey said that she had no relevant disclosures.

NEW ORLEANS – Suspect an allergic reaction to inactive ingredients in topical corticosteroids when patients do not improve despite usual treatment regimens, a retrospective study suggests.

"An allergy prevalence of 4% for an emulsifier widely used in corticosteroids and personal care products is very important," Brienne Danielle Cressey said at the annual meeting of the American Contact Dermatitis Society.

Ms. Cressey and her associates in the dermatology department at Tufts Medical Center, Boston, reviewed charts of 591 patients who were patch-tested between November 2008 and May 2010. They found that 24 of these patients (4.1%) had positive reactions to a sorbitan emulsifier found in many corticosteroid formulations.

Specifically, 3.9% reacted positively to sorbitan sesquioleate (SSO); 0.85% to sorbitan monooleate (SMO); and 0.7% to both.

"It was thought previously to be an uncommon allergen," said Ms. Cressey, a student at the Maine Medical Center Tufts University School of Medicine (class of 2013) in Portland. In a previous study conducted at Tufts University, researchers found an 8.9% prevalence of sorbitan allergy among 112 dermatitis patients (Dermatitis 2008;19:323-7).

Even though sorbitan allergy was less common in the current study, "we feel it's still an important allergen, with a prevalence greater than 1%." These emulsifiers are not included in the standard patch-testing series, Ms. Cressey said.

Patients were patch-tested using the Tufts Medical Center standard series and a preservative series containing SSO in 20% petrolatum and SMO 5% in petrolatum. Results were read at 48 and 72 hours. The majority were weak reactors: 22 patients were + and 2 were ++. "Our only two patients with 2+ reactions were children with generalized dermatitis," Ms. Cressey said.

Only one patient reacted to any of the four different corticosteroid screening chemicals tested, confirming that these reactions were caused by the sorbitan emulsifiers.

In the positive reaction group, the average duration of contact dermatitis was 43 months, the mean age was 40 years, and 46% were atopic. Dermatitis of the upper extremity and face was the most common.

The sources of sorbitan exposure were personal care products (10 patients), topical corticosteroids (9 patients), and ingestion (5 patients). Ingestion included, for example, sorbitans as a medication ingredient, Ms. Cressey said. "One patient with axillary dermatitis was using deodorant with sorbitol," she added.

The fact that the majority of reactions to SSO were weak raises a question as to whether this emulsifier is a contact or irritant allergen, Ms. Cressey said. Because 27 of 591 patients also were questionable for SSO reactions, "SSO is most likely not an irritant," she said.

In addition to topical corticosteroids, sorbitol-based emulsifiers are found in topical antibiotics, topical antifungals, topical retinoids, and moisturizing creams and lotions (Dermatitis 2008;19:339-41). This publication includes a list of products that commonly contain SSO, sorbitol, and sorbitol derivatives.

Ms. Cressey said that she had no relevant disclosures.

NEW ORLEANS – Dimethyl fumarate – a volatile substance included in shipments of furniture, clothing, and shoes to inhibit growth of mold – earned the distinction as the American Contact Dermatitis Society's 2011 Allergen of the Year.

"We had a difficult decision," Dr. Donald V. Belsito said. "But we decided to go with dimethyl fumarate. It caused an epidemic in Europe starting in 2007."

The substance is now being regulated in Europe, "although apparently some stuff is still sneaking through," Dr. Belsito said. "To date, I know of no cases in the U.S., although Dr. Melanie Pratt has had a few cases in Ontario."

Dimethyl fumarate "produces an extremely severe dermatitis," said Dr. Belsito, a dermatologist in private practice in Shawnee, Kan.

The unlikely story behind identification of this preservative and fungicide demonstrates the benefits of international collaboration, he noted.

First noted by dermatologists in Finland, cases of the severe dermatitis began to appear in Sweden and the U.K. The severe rash, seen predominantly on the backs of the legs, buttocks, and back, was an etiologic mystery. Through extensive sleuth work, Finnish dermatologists determined a common link – each person recently purchased furniture from a particular Chinese manufacturer.

It then became commonly called "sofa dermatitis." A contact allergy to the upholstery fabric was initially suspected. However, no common chemical or fabric was identified among the different pieces of furniture purchased by affected patients.

Dr. Magnus Bruze, an occupational and environmental dermatologist at Malmo University in Sweden, and other investigators took apart the furniture, patch tested 40 affected patients to various components, and eventually identified the culprit: dimethyl fumarate. The allergen was enclosed in packets similar in appearance to silicone packets often labeled "Warning: Do Not Eat."

Dimethyl fumarate is so volatile it can vaporize within 6 weeks. The vapors cause the dermatitis – sometimes spread out and sometimes patchy – after permeating the sofas, clothing, and shoe products during shipment.

Particularly concerning is very low exposure levels to dimethyl fumarate can trigger a reaction, concentrations well below those of common contact dermatitis allergens.

In an unprecedented move, Dr. Belsito revealed the leading contender, at least for now, for the 2012 Allergen of the Year: acrylates and methacrylates. Acrylates and methacrylates are polymers and adhesives. Methacrylate, for example, is used as bone cement for prosthetic devices placed during orthopedic surgery. The ACDS is soliciting feedback from members about naming this class of compounds at their next Allergen of the Year.

Neomcyin was the 2010 Allergen of the Year. Dr. Belsito described neomycin reactions as "common, not readily recognized, and problematic." Neomycin was chosen because of its widespread use as an over-the-counter antibiotic product; its high propensity for cross-reaction with other agents in the aminoglycoside class, including gentamicin, kanamycin, and tobramycin; and because neomycin is included as a preservative in some vaccines. Because a neomycin allergy is not a type 1 IgE-mediated, a reaction results in eczema, not anaphylaxis and death.

Gold was the 2001 Allergen of the Year, and reactions to gold are common and clinically problematic. Bacitracin (2003) and glucocorticosteroids (2005) are other allergens that are both common and clinically relevant. In contrast, thimerosal (2002) is a common but nonrelevant allergen because it has been removed from most products in the United States. A reaction to mixed dialkyl thioureas (2009), used in production of rubber products, is relatively uncommon but important when it occurs.

Dr. Belsito said that he had no relevant disclosures.

NEW ORLEANS – Dimethyl fumarate – a volatile substance included in shipments of furniture, clothing, and shoes to inhibit growth of mold – earned the distinction as the American Contact Dermatitis Society's 2011 Allergen of the Year.

"We had a difficult decision," Dr. Donald V. Belsito said. "But we decided to go with dimethyl fumarate. It caused an epidemic in Europe starting in 2007."

The substance is now being regulated in Europe, "although apparently some stuff is still sneaking through," Dr. Belsito said. "To date, I know of no cases in the U.S., although Dr. Melanie Pratt has had a few cases in Ontario."

Dimethyl fumarate "produces an extremely severe dermatitis," said Dr. Belsito, a dermatologist in private practice in Shawnee, Kan.

The unlikely story behind identification of this preservative and fungicide demonstrates the benefits of international collaboration, he noted.

First noted by dermatologists in Finland, cases of the severe dermatitis began to appear in Sweden and the U.K. The severe rash, seen predominantly on the backs of the legs, buttocks, and back, was an etiologic mystery. Through extensive sleuth work, Finnish dermatologists determined a common link – each person recently purchased furniture from a particular Chinese manufacturer.

It then became commonly called "sofa dermatitis." A contact allergy to the upholstery fabric was initially suspected. However, no common chemical or fabric was identified among the different pieces of furniture purchased by affected patients.

Dr. Magnus Bruze, an occupational and environmental dermatologist at Malmo University in Sweden, and other investigators took apart the furniture, patch tested 40 affected patients to various components, and eventually identified the culprit: dimethyl fumarate. The allergen was enclosed in packets similar in appearance to silicone packets often labeled "Warning: Do Not Eat."

Dimethyl fumarate is so volatile it can vaporize within 6 weeks. The vapors cause the dermatitis – sometimes spread out and sometimes patchy – after permeating the sofas, clothing, and shoe products during shipment.

Particularly concerning is very low exposure levels to dimethyl fumarate can trigger a reaction, concentrations well below those of common contact dermatitis allergens.

In an unprecedented move, Dr. Belsito revealed the leading contender, at least for now, for the 2012 Allergen of the Year: acrylates and methacrylates. Acrylates and methacrylates are polymers and adhesives. Methacrylate, for example, is used as bone cement for prosthetic devices placed during orthopedic surgery. The ACDS is soliciting feedback from members about naming this class of compounds at their next Allergen of the Year.

Neomcyin was the 2010 Allergen of the Year. Dr. Belsito described neomycin reactions as "common, not readily recognized, and problematic." Neomycin was chosen because of its widespread use as an over-the-counter antibiotic product; its high propensity for cross-reaction with other agents in the aminoglycoside class, including gentamicin, kanamycin, and tobramycin; and because neomycin is included as a preservative in some vaccines. Because a neomycin allergy is not a type 1 IgE-mediated, a reaction results in eczema, not anaphylaxis and death.

Gold was the 2001 Allergen of the Year, and reactions to gold are common and clinically problematic. Bacitracin (2003) and glucocorticosteroids (2005) are other allergens that are both common and clinically relevant. In contrast, thimerosal (2002) is a common but nonrelevant allergen because it has been removed from most products in the United States. A reaction to mixed dialkyl thioureas (2009), used in production of rubber products, is relatively uncommon but important when it occurs.

Dr. Belsito said that he had no relevant disclosures.

NEW ORLEANS – Dimethyl fumarate – a volatile substance included in shipments of furniture, clothing, and shoes to inhibit growth of mold – earned the distinction as the American Contact Dermatitis Society's 2011 Allergen of the Year.

"We had a difficult decision," Dr. Donald V. Belsito said. "But we decided to go with dimethyl fumarate. It caused an epidemic in Europe starting in 2007."

The substance is now being regulated in Europe, "although apparently some stuff is still sneaking through," Dr. Belsito said. "To date, I know of no cases in the U.S., although Dr. Melanie Pratt has had a few cases in Ontario."

Dimethyl fumarate "produces an extremely severe dermatitis," said Dr. Belsito, a dermatologist in private practice in Shawnee, Kan.

The unlikely story behind identification of this preservative and fungicide demonstrates the benefits of international collaboration, he noted.

First noted by dermatologists in Finland, cases of the severe dermatitis began to appear in Sweden and the U.K. The severe rash, seen predominantly on the backs of the legs, buttocks, and back, was an etiologic mystery. Through extensive sleuth work, Finnish dermatologists determined a common link – each person recently purchased furniture from a particular Chinese manufacturer.

It then became commonly called "sofa dermatitis." A contact allergy to the upholstery fabric was initially suspected. However, no common chemical or fabric was identified among the different pieces of furniture purchased by affected patients.

Dr. Magnus Bruze, an occupational and environmental dermatologist at Malmo University in Sweden, and other investigators took apart the furniture, patch tested 40 affected patients to various components, and eventually identified the culprit: dimethyl fumarate. The allergen was enclosed in packets similar in appearance to silicone packets often labeled "Warning: Do Not Eat."

Dimethyl fumarate is so volatile it can vaporize within 6 weeks. The vapors cause the dermatitis – sometimes spread out and sometimes patchy – after permeating the sofas, clothing, and shoe products during shipment.

Particularly concerning is very low exposure levels to dimethyl fumarate can trigger a reaction, concentrations well below those of common contact dermatitis allergens.

In an unprecedented move, Dr. Belsito revealed the leading contender, at least for now, for the 2012 Allergen of the Year: acrylates and methacrylates. Acrylates and methacrylates are polymers and adhesives. Methacrylate, for example, is used as bone cement for prosthetic devices placed during orthopedic surgery. The ACDS is soliciting feedback from members about naming this class of compounds at their next Allergen of the Year.

Neomcyin was the 2010 Allergen of the Year. Dr. Belsito described neomycin reactions as "common, not readily recognized, and problematic." Neomycin was chosen because of its widespread use as an over-the-counter antibiotic product; its high propensity for cross-reaction with other agents in the aminoglycoside class, including gentamicin, kanamycin, and tobramycin; and because neomycin is included as a preservative in some vaccines. Because a neomycin allergy is not a type 1 IgE-mediated, a reaction results in eczema, not anaphylaxis and death.

Gold was the 2001 Allergen of the Year, and reactions to gold are common and clinically problematic. Bacitracin (2003) and glucocorticosteroids (2005) are other allergens that are both common and clinically relevant. In contrast, thimerosal (2002) is a common but nonrelevant allergen because it has been removed from most products in the United States. A reaction to mixed dialkyl thioureas (2009), used in production of rubber products, is relatively uncommon but important when it occurs.

Dr. Belsito said that he had no relevant disclosures.

LAS VEGAS – Immunosuppressive drug therapy is not an absolute contraindication for allergy patch testing, according to Dr. Joseph F. Fowler Jr.

A recent report on 11 patients who underwent patch testing while on a variety of systemic immunosuppressive drugs suggested patch testing may be more successful than many clinicians think, Dr. Fowler said. Speaking at the seminar sponsored by Skin Disease Education Foundation (SDEF), he fleshed out the findings with advice from his own experience in patch testing patients on immunosuppressives.

The retrospective chart review included patients on prednisone, cyclosporine, mycophenolate mofetil, or infliximab (Dermatitis 2009;20:265-70).

All but one of the patients who were taking 10 mg/day of prednisone had positive patch test reactions, said Dr. Fowler of the University of Louisville (Ky.) and president of the North American Contact Dermatitis Group.

"In the past, we had thought that about 10 mg/day was the maximum" prednisone dose that could still allow successful patch testing, but this belief was based on extrapolations of animal studies and case reports, with no hard data, he said. "I have personally seen patients who are on higher doses of prednisone produce good positive reactions."

Ideally, though, it’s best to patch test when patients are off prednisone, or on doses of 10 mg/day or less, he added. "If you could get them on every-other-day prednisone dosing, that would be even better."

For an untreated patient with fairly bad dermatitis, especially on the back, Dr. Fowler may treat for 5-7 days with a corticosteroid, perhaps prednisone 40-60 mg/day with no taper, and then stop the corticosteroid for 2-3 days before patch testing. "That’s one way you can get a person clear enough to patch test them if they’re already broken out," he said.

If the patient already is on chronic corticosteroid therapy, he tries to reduce the dose to 10 mg/day or less for several weeks before patch testing.

Dr. Fowler was surprised patients in the report who were being treated with cyclosporine 200 or 300 mg/day all had positive reactions to patch testing. "Generally, we expect cyclosporine to reduce the likelihood of positive reactions because of its broad immunosuppressant effect," he said. "These folks were on relatively low doses, so maybe that was a factor." In his own experience, Dr. Fowler said he has rarely seen positive reactions to patch testing in patients on cyclosporine, "so I think that’s problematic," he added.

One patient on mycophenolate (CellCept) 2 g/day had a negative result when patch tested but then stopped the drug and had a positive reaction on repeat patch testing. "That would suggest that the CellCept suppressed reactions," Dr. Fowler said. He advised not patch testing patients who are on CellCept, cyclosporine, tacrolimus, or azathioprine if at all possible.

One patient on infliximab (Remicade) whose last infusion occurred 3 weeks before patch testing developed multiple positive reactions. "That mirrors what I’ve been perceiving in clinical practice," he said.

Use of methotrexate or tumor necrosis factor–alpha inhibitors such as Remicade or etanercept (Enbrel) should not prevent patch testing. "I’ve had no problem patch testing people on methotrexate," Dr. Fowler said.

The report did not include antihistamines, which also are not a barrier to patch testing. "Other docs, allergists especially, tell patients they can’t take antihistamines when they’re being patch tested," he explained. "They may not be able to take antihistamines and get a good scratch test result, but remember in patch testing you’re looking at a T cell–mediated process. Antihistamines have essentially no effect on that."

Dr. Fowler has been a consultant, speaker, or researcher for Coria, Galderma, Graceway, Hyland, Johnson & Johnson, Quinnova, Ranbaxy, Shire, Stiefel, Triax, UCB, Medicis, Novartis, Abbott, Taro, Allerderm, Allergan, Amgen, Astellas, Centocor, Dermik, Dow, Genentech, Taisho, and 3M.

SDEF and this news organization are owned by Elsevier.

LAS VEGAS – Immunosuppressive drug therapy is not an absolute contraindication for allergy patch testing, according to Dr. Joseph F. Fowler Jr.

A recent report on 11 patients who underwent patch testing while on a variety of systemic immunosuppressive drugs suggested patch testing may be more successful than many clinicians think, Dr. Fowler said. Speaking at the seminar sponsored by Skin Disease Education Foundation (SDEF), he fleshed out the findings with advice from his own experience in patch testing patients on immunosuppressives.

The retrospective chart review included patients on prednisone, cyclosporine, mycophenolate mofetil, or infliximab (Dermatitis 2009;20:265-70).

All but one of the patients who were taking 10 mg/day of prednisone had positive patch test reactions, said Dr. Fowler of the University of Louisville (Ky.) and president of the North American Contact Dermatitis Group.

"In the past, we had thought that about 10 mg/day was the maximum" prednisone dose that could still allow successful patch testing, but this belief was based on extrapolations of animal studies and case reports, with no hard data, he said. "I have personally seen patients who are on higher doses of prednisone produce good positive reactions."

Ideally, though, it’s best to patch test when patients are off prednisone, or on doses of 10 mg/day or less, he added. "If you could get them on every-other-day prednisone dosing, that would be even better."

For an untreated patient with fairly bad dermatitis, especially on the back, Dr. Fowler may treat for 5-7 days with a corticosteroid, perhaps prednisone 40-60 mg/day with no taper, and then stop the corticosteroid for 2-3 days before patch testing. "That’s one way you can get a person clear enough to patch test them if they’re already broken out," he said.

If the patient already is on chronic corticosteroid therapy, he tries to reduce the dose to 10 mg/day or less for several weeks before patch testing.

Dr. Fowler was surprised patients in the report who were being treated with cyclosporine 200 or 300 mg/day all had positive reactions to patch testing. "Generally, we expect cyclosporine to reduce the likelihood of positive reactions because of its broad immunosuppressant effect," he said. "These folks were on relatively low doses, so maybe that was a factor." In his own experience, Dr. Fowler said he has rarely seen positive reactions to patch testing in patients on cyclosporine, "so I think that’s problematic," he added.

One patient on mycophenolate (CellCept) 2 g/day had a negative result when patch tested but then stopped the drug and had a positive reaction on repeat patch testing. "That would suggest that the CellCept suppressed reactions," Dr. Fowler said. He advised not patch testing patients who are on CellCept, cyclosporine, tacrolimus, or azathioprine if at all possible.

One patient on infliximab (Remicade) whose last infusion occurred 3 weeks before patch testing developed multiple positive reactions. "That mirrors what I’ve been perceiving in clinical practice," he said.

Use of methotrexate or tumor necrosis factor–alpha inhibitors such as Remicade or etanercept (Enbrel) should not prevent patch testing. "I’ve had no problem patch testing people on methotrexate," Dr. Fowler said.

The report did not include antihistamines, which also are not a barrier to patch testing. "Other docs, allergists especially, tell patients they can’t take antihistamines when they’re being patch tested," he explained. "They may not be able to take antihistamines and get a good scratch test result, but remember in patch testing you’re looking at a T cell–mediated process. Antihistamines have essentially no effect on that."

Dr. Fowler has been a consultant, speaker, or researcher for Coria, Galderma, Graceway, Hyland, Johnson & Johnson, Quinnova, Ranbaxy, Shire, Stiefel, Triax, UCB, Medicis, Novartis, Abbott, Taro, Allerderm, Allergan, Amgen, Astellas, Centocor, Dermik, Dow, Genentech, Taisho, and 3M.

SDEF and this news organization are owned by Elsevier.

LAS VEGAS – Immunosuppressive drug therapy is not an absolute contraindication for allergy patch testing, according to Dr. Joseph F. Fowler Jr.

A recent report on 11 patients who underwent patch testing while on a variety of systemic immunosuppressive drugs suggested patch testing may be more successful than many clinicians think, Dr. Fowler said. Speaking at the seminar sponsored by Skin Disease Education Foundation (SDEF), he fleshed out the findings with advice from his own experience in patch testing patients on immunosuppressives.

The retrospective chart review included patients on prednisone, cyclosporine, mycophenolate mofetil, or infliximab (Dermatitis 2009;20:265-70).

All but one of the patients who were taking 10 mg/day of prednisone had positive patch test reactions, said Dr. Fowler of the University of Louisville (Ky.) and president of the North American Contact Dermatitis Group.

"In the past, we had thought that about 10 mg/day was the maximum" prednisone dose that could still allow successful patch testing, but this belief was based on extrapolations of animal studies and case reports, with no hard data, he said. "I have personally seen patients who are on higher doses of prednisone produce good positive reactions."

Ideally, though, it’s best to patch test when patients are off prednisone, or on doses of 10 mg/day or less, he added. "If you could get them on every-other-day prednisone dosing, that would be even better."

For an untreated patient with fairly bad dermatitis, especially on the back, Dr. Fowler may treat for 5-7 days with a corticosteroid, perhaps prednisone 40-60 mg/day with no taper, and then stop the corticosteroid for 2-3 days before patch testing. "That’s one way you can get a person clear enough to patch test them if they’re already broken out," he said.

If the patient already is on chronic corticosteroid therapy, he tries to reduce the dose to 10 mg/day or less for several weeks before patch testing.

Dr. Fowler was surprised patients in the report who were being treated with cyclosporine 200 or 300 mg/day all had positive reactions to patch testing. "Generally, we expect cyclosporine to reduce the likelihood of positive reactions because of its broad immunosuppressant effect," he said. "These folks were on relatively low doses, so maybe that was a factor." In his own experience, Dr. Fowler said he has rarely seen positive reactions to patch testing in patients on cyclosporine, "so I think that’s problematic," he added.

One patient on mycophenolate (CellCept) 2 g/day had a negative result when patch tested but then stopped the drug and had a positive reaction on repeat patch testing. "That would suggest that the CellCept suppressed reactions," Dr. Fowler said. He advised not patch testing patients who are on CellCept, cyclosporine, tacrolimus, or azathioprine if at all possible.

One patient on infliximab (Remicade) whose last infusion occurred 3 weeks before patch testing developed multiple positive reactions. "That mirrors what I’ve been perceiving in clinical practice," he said.

Use of methotrexate or tumor necrosis factor–alpha inhibitors such as Remicade or etanercept (Enbrel) should not prevent patch testing. "I’ve had no problem patch testing people on methotrexate," Dr. Fowler said.

The report did not include antihistamines, which also are not a barrier to patch testing. "Other docs, allergists especially, tell patients they can’t take antihistamines when they’re being patch tested," he explained. "They may not be able to take antihistamines and get a good scratch test result, but remember in patch testing you’re looking at a T cell–mediated process. Antihistamines have essentially no effect on that."

Dr. Fowler has been a consultant, speaker, or researcher for Coria, Galderma, Graceway, Hyland, Johnson & Johnson, Quinnova, Ranbaxy, Shire, Stiefel, Triax, UCB, Medicis, Novartis, Abbott, Taro, Allerderm, Allergan, Amgen, Astellas, Centocor, Dermik, Dow, Genentech, Taisho, and 3M.

SDEF and this news organization are owned by Elsevier.