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Look for functional esophageal disorders if GERD patients fail PPIs
In a small, first-in-kind study, functional heartburn or reflux hypersensitivity affected fully 75% of patients whose gastroesophageal reflux disease symptoms had not improved with once-daily proton pump inhibitor therapy.
At the same time, proton pump inhibitor (PPI) responders and nonresponders had similar impedance and pH parameters, reported Jason Abdallah, MD, of Case Western Reserve University, Cleveland, and his associates. The findings show “the important role of esophageal hypersensitivity in this patient population.” For these patients, the investigators suggested adding a neuromodulator and possibly psychotherapy, such as cognitive-behavioral therapy, hypnotherapy, relaxation techniques, mindfulness, and biofeedback.
Symptoms in up to 45% of patients with gastroesophageal reflux disease (GERD) persist despite once-daily PPI therapy, Dr. Abdallah and his associates wrote in Clinical Gastroenterology and Hepatology. For the study, they compared reflux characteristics and patterns between 13 patients whose GERD symptoms had fully resolved on standard once-daily PPIs and 16 patients who reported at least twice-weekly heartburn, regurgitation, or both for at least 3 months, despite treatment. Patients in both groups continued PPIs and underwent upper endoscopy and combined esophageal impedance–pH monitoring.
The average age of patients in this study was 54.5 years, with a standard deviation of 14.5 years. Demographic and clinical characteristics were similar between groups, and patients in both groups were receiving omeprazole, esomeprazole, or pantoprazole. Four (31%) PPI responders had abnormal pH test results, as did four (25%) nonresponders. Responders and nonresponders had similar numbers of reflux events; proportions of events that were acidic, weakly acidic, or alkaline; and mean total time with pH less than 4.0.
Additionally, most patients in both groups had normal endoscopic findings. One PPI responder had Los Angeles grade A erosive esophagitis, and two PPI responders had short-segment Barrett’s esophagus. Three PPI responders and two PPI nonresponders had nonobstructive Schatzki rings, and one PPI nonresponder had an esophageal stricture. Finally, five PPI responders (38%) and three nonresponders (19%) had hiatal hernias (P = .41).
In patients with GERD, “PPI failure” does not reflect a unique pattern of reflux events, acid exposure, or nonacidic reflux parameters, Dr. Abdallah and his associates concluded. The fact that most PPI nonresponders had a concurrent functional esophageal disorder – either reflux hypersensitivity or functional heartburn – “support[s] the hypothesis that PPI failure is primarily driven by esophageal hypersensitivity.”
This was a small study – recruitment “was hampered by the invasive nature of some of the procedures,” they wrote. “In addition, it is our experience that many patients who have responded to PPI [therapy] are reluctant to undergo invasive testing as part of a study protocol. Therefore, we believe that these types of prospective, invasive studies are rather difficult to perform but, at the same time, provide essential insight into the understanding of refractory GERD.”
No external funding sources were acknowledged. The senior author reported ties to Ironwood Pharmaceuticals, Mederi Therapeutics, Ethicon, AstraZeneca, and Takeda. The other researchers reported no conflicts of interest.
SOURCE: Abdallah J et al. Clin Gastroenterol Hepatol. 2018 Jun 15. doi: 10.1016/j.cgh.2018.09.006.
In a small, first-in-kind study, functional heartburn or reflux hypersensitivity affected fully 75% of patients whose gastroesophageal reflux disease symptoms had not improved with once-daily proton pump inhibitor therapy.
At the same time, proton pump inhibitor (PPI) responders and nonresponders had similar impedance and pH parameters, reported Jason Abdallah, MD, of Case Western Reserve University, Cleveland, and his associates. The findings show “the important role of esophageal hypersensitivity in this patient population.” For these patients, the investigators suggested adding a neuromodulator and possibly psychotherapy, such as cognitive-behavioral therapy, hypnotherapy, relaxation techniques, mindfulness, and biofeedback.
Symptoms in up to 45% of patients with gastroesophageal reflux disease (GERD) persist despite once-daily PPI therapy, Dr. Abdallah and his associates wrote in Clinical Gastroenterology and Hepatology. For the study, they compared reflux characteristics and patterns between 13 patients whose GERD symptoms had fully resolved on standard once-daily PPIs and 16 patients who reported at least twice-weekly heartburn, regurgitation, or both for at least 3 months, despite treatment. Patients in both groups continued PPIs and underwent upper endoscopy and combined esophageal impedance–pH monitoring.
The average age of patients in this study was 54.5 years, with a standard deviation of 14.5 years. Demographic and clinical characteristics were similar between groups, and patients in both groups were receiving omeprazole, esomeprazole, or pantoprazole. Four (31%) PPI responders had abnormal pH test results, as did four (25%) nonresponders. Responders and nonresponders had similar numbers of reflux events; proportions of events that were acidic, weakly acidic, or alkaline; and mean total time with pH less than 4.0.
Additionally, most patients in both groups had normal endoscopic findings. One PPI responder had Los Angeles grade A erosive esophagitis, and two PPI responders had short-segment Barrett’s esophagus. Three PPI responders and two PPI nonresponders had nonobstructive Schatzki rings, and one PPI nonresponder had an esophageal stricture. Finally, five PPI responders (38%) and three nonresponders (19%) had hiatal hernias (P = .41).
In patients with GERD, “PPI failure” does not reflect a unique pattern of reflux events, acid exposure, or nonacidic reflux parameters, Dr. Abdallah and his associates concluded. The fact that most PPI nonresponders had a concurrent functional esophageal disorder – either reflux hypersensitivity or functional heartburn – “support[s] the hypothesis that PPI failure is primarily driven by esophageal hypersensitivity.”
This was a small study – recruitment “was hampered by the invasive nature of some of the procedures,” they wrote. “In addition, it is our experience that many patients who have responded to PPI [therapy] are reluctant to undergo invasive testing as part of a study protocol. Therefore, we believe that these types of prospective, invasive studies are rather difficult to perform but, at the same time, provide essential insight into the understanding of refractory GERD.”
No external funding sources were acknowledged. The senior author reported ties to Ironwood Pharmaceuticals, Mederi Therapeutics, Ethicon, AstraZeneca, and Takeda. The other researchers reported no conflicts of interest.
SOURCE: Abdallah J et al. Clin Gastroenterol Hepatol. 2018 Jun 15. doi: 10.1016/j.cgh.2018.09.006.
In a small, first-in-kind study, functional heartburn or reflux hypersensitivity affected fully 75% of patients whose gastroesophageal reflux disease symptoms had not improved with once-daily proton pump inhibitor therapy.
At the same time, proton pump inhibitor (PPI) responders and nonresponders had similar impedance and pH parameters, reported Jason Abdallah, MD, of Case Western Reserve University, Cleveland, and his associates. The findings show “the important role of esophageal hypersensitivity in this patient population.” For these patients, the investigators suggested adding a neuromodulator and possibly psychotherapy, such as cognitive-behavioral therapy, hypnotherapy, relaxation techniques, mindfulness, and biofeedback.
Symptoms in up to 45% of patients with gastroesophageal reflux disease (GERD) persist despite once-daily PPI therapy, Dr. Abdallah and his associates wrote in Clinical Gastroenterology and Hepatology. For the study, they compared reflux characteristics and patterns between 13 patients whose GERD symptoms had fully resolved on standard once-daily PPIs and 16 patients who reported at least twice-weekly heartburn, regurgitation, or both for at least 3 months, despite treatment. Patients in both groups continued PPIs and underwent upper endoscopy and combined esophageal impedance–pH monitoring.
The average age of patients in this study was 54.5 years, with a standard deviation of 14.5 years. Demographic and clinical characteristics were similar between groups, and patients in both groups were receiving omeprazole, esomeprazole, or pantoprazole. Four (31%) PPI responders had abnormal pH test results, as did four (25%) nonresponders. Responders and nonresponders had similar numbers of reflux events; proportions of events that were acidic, weakly acidic, or alkaline; and mean total time with pH less than 4.0.
Additionally, most patients in both groups had normal endoscopic findings. One PPI responder had Los Angeles grade A erosive esophagitis, and two PPI responders had short-segment Barrett’s esophagus. Three PPI responders and two PPI nonresponders had nonobstructive Schatzki rings, and one PPI nonresponder had an esophageal stricture. Finally, five PPI responders (38%) and three nonresponders (19%) had hiatal hernias (P = .41).
In patients with GERD, “PPI failure” does not reflect a unique pattern of reflux events, acid exposure, or nonacidic reflux parameters, Dr. Abdallah and his associates concluded. The fact that most PPI nonresponders had a concurrent functional esophageal disorder – either reflux hypersensitivity or functional heartburn – “support[s] the hypothesis that PPI failure is primarily driven by esophageal hypersensitivity.”
This was a small study – recruitment “was hampered by the invasive nature of some of the procedures,” they wrote. “In addition, it is our experience that many patients who have responded to PPI [therapy] are reluctant to undergo invasive testing as part of a study protocol. Therefore, we believe that these types of prospective, invasive studies are rather difficult to perform but, at the same time, provide essential insight into the understanding of refractory GERD.”
No external funding sources were acknowledged. The senior author reported ties to Ironwood Pharmaceuticals, Mederi Therapeutics, Ethicon, AstraZeneca, and Takeda. The other researchers reported no conflicts of interest.
SOURCE: Abdallah J et al. Clin Gastroenterol Hepatol. 2018 Jun 15. doi: 10.1016/j.cgh.2018.09.006.
FROM CLINICAL GASTROENTEROLOGY AND HEPATOLOGY
No biopsy for 21% of adults with celiac disease
Patients with celiac disease often do not receive a biopsy or nutritional recommendations at diagnosis, according to the findings of a large survey study.
Strikingly, 21% of respondents did not have a confirmatory duodenal biopsy, reported Andrew M. Joelson, MD, of Columbia University Medical Center, New York, and his associates. Gastroenterologists diagnosed 66% of biopsied patients but only 31% of nonbiopsied patients (P less than .001). “Patients require more education about management of celiac disease and referral to gastroenterologists for duodenal biopsy confirmation,” the researchers wrote in the May issue of Clinical Gastroenterology and Hepatology.
Classic small-bowel findings in celiac disease (intraepithelial lymphocytes, crypt hyperplasia, and villous atrophy) are not pathognomonic, making serology important for diagnosis. European guidelines discuss forgoing biopsy in children whose antitissue transglutaminase antibody titers are at least 10-fold above the upper limit of normal. However, the American College of Gastroenterology and the American Gastroenterological Association continue to recommend combining serology with confirmatory small bowel biopsy. The extent to which physicians follow this advice is unclear, the researchers noted.
Therefore, they analyzed data from a questionnaire posted on the Celiac Disease Foundation website during a 7-month period in 2016. Among 982 adults with self-reported celiac disease, 780 said their diagnosis included both serology and biopsy and 202 said they received serology only. Only 40% of these nonbiopsied respondents said they sought nutritional counseling at diagnosis, compared with 59% of biopsied patients (P less than .001). Patients diagnosed by serology alone also were more likely to report using dietary supplements to aid gluten digestion (20% vs. 9% of biopsied respondents; P less than .001).
These associations remained statistically significant after adjustment for age and sex, said the researchers. Nonbiopsied patients had a significantly lower odds of having been diagnosed by a gastroenterologist (odds ratio, 0.16; 95% confidence interval, 0.07-0.37) and seeking nutritional counseling (OR, 0.45; 95% CI, 0.33-0.63) and were significantly more likely to use digestive supplements (OR, 2.61; 95%, CI 1.62-4.19).
Fully 87% of respondents always followed a strict gluten-free diet, but symptoms persisted in 65% of those who were not biopsied, compared with only 51% of those who were biopsied. There were too few responses to this question for the difference between groups to reach statistical significance, but the finding might reflect the greater diagnostic accuracy of biopsy, the researchers said. However, they cautioned that none of the associations in this study were necessarily causal, diagnoses were not independently validated, and the reliability of self-reported celiac diagnosis remains unclear.
Survey respondents also were self-selected – for example, 91% self-identified as white and 60% reported having a bachelor’s degree, compared with only about 77% and one-third of adults captured by U.S. Census Bureau data from 2017.
“Although these characteristics may limit the generalizability of our findings, this study nevertheless reflects a population of celiac disease that is not typically studied, such as those not attending large academic celiac disease centers, and those diagnosed without the involvement of a gastroenterologist,” the researchers wrote. “Future studies are warranted to further characterize this population regarding the long-term consequences of forgoing the duodenal biopsy, and to develop educational interventions to promote evidence-based diagnosis and management of celiac disease.”
SOURCE: Joelson AM et al. Clin Gastroenterol Hepatol. 2018 Sep 10. doi: 10.1016/j.cgh.2018.09.006.
Self-reported celiac disease diagnosis is not validated and perhaps more inaccurate now with the rise of other gluten-related disorders. Although misdiagnosis is possible, the finding in this study by Joelson et al. that 21% of self-reported celiac adults said they never had a confirmatory biopsy is remarkable. Another important observation is the low-quality celiac care among nonbiopsed adults, with less formal nutritional counseling and high use of gluten digestive supplements and persistent symptoms.
Unfortunately, the reason why confirmatory biopsy was missed is unknown. The approach to confirm a diagnosis of celiac disease is changing. A few decades ago, celiac disease diagnosis required three sequential duodenal biopsies (baseline, on gluten-free diet, and after gluten challenge). More recently, the availability of more specific serology made multiple sequential biopsies unnecessary. However, a confirmatory biopsy was mandatory.
Nowadays, biopsy confirmation may not be necessary for all. There is strong evidence for nonbiopsy diagnosis in selected symptomatic children with high titers of tissue transglutaminase antibodies (more than 10 times the upper limit of normal) and a positive endomysial antibody in a second sample. Whether the nonbiopsy approach could be applicable also in adults remains controversial. Current guidelines recommend biopsy confirmation in all adults. However, emerging evidence favors celiac disease diagnosis without use of biopsy in selected adults.
Although the debate regarding pros and cons of nonbiopsy diagnosis is far from an end, this approach is here to stay. In the future, regardless of the method selected to confirm celiac disease diagnosis, the overall quality of celiac care should be ensured.
Alberto Rubio-Tapia, MD, is an assistant professor of medicine at the Mayo Clinic, Rochester, Minn. He has no conflicts of interest.
Self-reported celiac disease diagnosis is not validated and perhaps more inaccurate now with the rise of other gluten-related disorders. Although misdiagnosis is possible, the finding in this study by Joelson et al. that 21% of self-reported celiac adults said they never had a confirmatory biopsy is remarkable. Another important observation is the low-quality celiac care among nonbiopsed adults, with less formal nutritional counseling and high use of gluten digestive supplements and persistent symptoms.
Unfortunately, the reason why confirmatory biopsy was missed is unknown. The approach to confirm a diagnosis of celiac disease is changing. A few decades ago, celiac disease diagnosis required three sequential duodenal biopsies (baseline, on gluten-free diet, and after gluten challenge). More recently, the availability of more specific serology made multiple sequential biopsies unnecessary. However, a confirmatory biopsy was mandatory.
Nowadays, biopsy confirmation may not be necessary for all. There is strong evidence for nonbiopsy diagnosis in selected symptomatic children with high titers of tissue transglutaminase antibodies (more than 10 times the upper limit of normal) and a positive endomysial antibody in a second sample. Whether the nonbiopsy approach could be applicable also in adults remains controversial. Current guidelines recommend biopsy confirmation in all adults. However, emerging evidence favors celiac disease diagnosis without use of biopsy in selected adults.
Although the debate regarding pros and cons of nonbiopsy diagnosis is far from an end, this approach is here to stay. In the future, regardless of the method selected to confirm celiac disease diagnosis, the overall quality of celiac care should be ensured.
Alberto Rubio-Tapia, MD, is an assistant professor of medicine at the Mayo Clinic, Rochester, Minn. He has no conflicts of interest.
Self-reported celiac disease diagnosis is not validated and perhaps more inaccurate now with the rise of other gluten-related disorders. Although misdiagnosis is possible, the finding in this study by Joelson et al. that 21% of self-reported celiac adults said they never had a confirmatory biopsy is remarkable. Another important observation is the low-quality celiac care among nonbiopsed adults, with less formal nutritional counseling and high use of gluten digestive supplements and persistent symptoms.
Unfortunately, the reason why confirmatory biopsy was missed is unknown. The approach to confirm a diagnosis of celiac disease is changing. A few decades ago, celiac disease diagnosis required three sequential duodenal biopsies (baseline, on gluten-free diet, and after gluten challenge). More recently, the availability of more specific serology made multiple sequential biopsies unnecessary. However, a confirmatory biopsy was mandatory.
Nowadays, biopsy confirmation may not be necessary for all. There is strong evidence for nonbiopsy diagnosis in selected symptomatic children with high titers of tissue transglutaminase antibodies (more than 10 times the upper limit of normal) and a positive endomysial antibody in a second sample. Whether the nonbiopsy approach could be applicable also in adults remains controversial. Current guidelines recommend biopsy confirmation in all adults. However, emerging evidence favors celiac disease diagnosis without use of biopsy in selected adults.
Although the debate regarding pros and cons of nonbiopsy diagnosis is far from an end, this approach is here to stay. In the future, regardless of the method selected to confirm celiac disease diagnosis, the overall quality of celiac care should be ensured.
Alberto Rubio-Tapia, MD, is an assistant professor of medicine at the Mayo Clinic, Rochester, Minn. He has no conflicts of interest.
Patients with celiac disease often do not receive a biopsy or nutritional recommendations at diagnosis, according to the findings of a large survey study.
Strikingly, 21% of respondents did not have a confirmatory duodenal biopsy, reported Andrew M. Joelson, MD, of Columbia University Medical Center, New York, and his associates. Gastroenterologists diagnosed 66% of biopsied patients but only 31% of nonbiopsied patients (P less than .001). “Patients require more education about management of celiac disease and referral to gastroenterologists for duodenal biopsy confirmation,” the researchers wrote in the May issue of Clinical Gastroenterology and Hepatology.
Classic small-bowel findings in celiac disease (intraepithelial lymphocytes, crypt hyperplasia, and villous atrophy) are not pathognomonic, making serology important for diagnosis. European guidelines discuss forgoing biopsy in children whose antitissue transglutaminase antibody titers are at least 10-fold above the upper limit of normal. However, the American College of Gastroenterology and the American Gastroenterological Association continue to recommend combining serology with confirmatory small bowel biopsy. The extent to which physicians follow this advice is unclear, the researchers noted.
Therefore, they analyzed data from a questionnaire posted on the Celiac Disease Foundation website during a 7-month period in 2016. Among 982 adults with self-reported celiac disease, 780 said their diagnosis included both serology and biopsy and 202 said they received serology only. Only 40% of these nonbiopsied respondents said they sought nutritional counseling at diagnosis, compared with 59% of biopsied patients (P less than .001). Patients diagnosed by serology alone also were more likely to report using dietary supplements to aid gluten digestion (20% vs. 9% of biopsied respondents; P less than .001).
These associations remained statistically significant after adjustment for age and sex, said the researchers. Nonbiopsied patients had a significantly lower odds of having been diagnosed by a gastroenterologist (odds ratio, 0.16; 95% confidence interval, 0.07-0.37) and seeking nutritional counseling (OR, 0.45; 95% CI, 0.33-0.63) and were significantly more likely to use digestive supplements (OR, 2.61; 95%, CI 1.62-4.19).
Fully 87% of respondents always followed a strict gluten-free diet, but symptoms persisted in 65% of those who were not biopsied, compared with only 51% of those who were biopsied. There were too few responses to this question for the difference between groups to reach statistical significance, but the finding might reflect the greater diagnostic accuracy of biopsy, the researchers said. However, they cautioned that none of the associations in this study were necessarily causal, diagnoses were not independently validated, and the reliability of self-reported celiac diagnosis remains unclear.
Survey respondents also were self-selected – for example, 91% self-identified as white and 60% reported having a bachelor’s degree, compared with only about 77% and one-third of adults captured by U.S. Census Bureau data from 2017.
“Although these characteristics may limit the generalizability of our findings, this study nevertheless reflects a population of celiac disease that is not typically studied, such as those not attending large academic celiac disease centers, and those diagnosed without the involvement of a gastroenterologist,” the researchers wrote. “Future studies are warranted to further characterize this population regarding the long-term consequences of forgoing the duodenal biopsy, and to develop educational interventions to promote evidence-based diagnosis and management of celiac disease.”
SOURCE: Joelson AM et al. Clin Gastroenterol Hepatol. 2018 Sep 10. doi: 10.1016/j.cgh.2018.09.006.
Patients with celiac disease often do not receive a biopsy or nutritional recommendations at diagnosis, according to the findings of a large survey study.
Strikingly, 21% of respondents did not have a confirmatory duodenal biopsy, reported Andrew M. Joelson, MD, of Columbia University Medical Center, New York, and his associates. Gastroenterologists diagnosed 66% of biopsied patients but only 31% of nonbiopsied patients (P less than .001). “Patients require more education about management of celiac disease and referral to gastroenterologists for duodenal biopsy confirmation,” the researchers wrote in the May issue of Clinical Gastroenterology and Hepatology.
Classic small-bowel findings in celiac disease (intraepithelial lymphocytes, crypt hyperplasia, and villous atrophy) are not pathognomonic, making serology important for diagnosis. European guidelines discuss forgoing biopsy in children whose antitissue transglutaminase antibody titers are at least 10-fold above the upper limit of normal. However, the American College of Gastroenterology and the American Gastroenterological Association continue to recommend combining serology with confirmatory small bowel biopsy. The extent to which physicians follow this advice is unclear, the researchers noted.
Therefore, they analyzed data from a questionnaire posted on the Celiac Disease Foundation website during a 7-month period in 2016. Among 982 adults with self-reported celiac disease, 780 said their diagnosis included both serology and biopsy and 202 said they received serology only. Only 40% of these nonbiopsied respondents said they sought nutritional counseling at diagnosis, compared with 59% of biopsied patients (P less than .001). Patients diagnosed by serology alone also were more likely to report using dietary supplements to aid gluten digestion (20% vs. 9% of biopsied respondents; P less than .001).
These associations remained statistically significant after adjustment for age and sex, said the researchers. Nonbiopsied patients had a significantly lower odds of having been diagnosed by a gastroenterologist (odds ratio, 0.16; 95% confidence interval, 0.07-0.37) and seeking nutritional counseling (OR, 0.45; 95% CI, 0.33-0.63) and were significantly more likely to use digestive supplements (OR, 2.61; 95%, CI 1.62-4.19).
Fully 87% of respondents always followed a strict gluten-free diet, but symptoms persisted in 65% of those who were not biopsied, compared with only 51% of those who were biopsied. There were too few responses to this question for the difference between groups to reach statistical significance, but the finding might reflect the greater diagnostic accuracy of biopsy, the researchers said. However, they cautioned that none of the associations in this study were necessarily causal, diagnoses were not independently validated, and the reliability of self-reported celiac diagnosis remains unclear.
Survey respondents also were self-selected – for example, 91% self-identified as white and 60% reported having a bachelor’s degree, compared with only about 77% and one-third of adults captured by U.S. Census Bureau data from 2017.
“Although these characteristics may limit the generalizability of our findings, this study nevertheless reflects a population of celiac disease that is not typically studied, such as those not attending large academic celiac disease centers, and those diagnosed without the involvement of a gastroenterologist,” the researchers wrote. “Future studies are warranted to further characterize this population regarding the long-term consequences of forgoing the duodenal biopsy, and to develop educational interventions to promote evidence-based diagnosis and management of celiac disease.”
SOURCE: Joelson AM et al. Clin Gastroenterol Hepatol. 2018 Sep 10. doi: 10.1016/j.cgh.2018.09.006.
FROM CLINICAL GASTROENTEROLOGY AND HEPATOLOGY
Studies link TMAO to microbiome, reveal new heart disease target
MIAMI – Researchers are one step closer to developing “drugs for bugs” – agents that target the gut microbiome to prevent and treat cardiometabolic diseases, Stanley L. Hazen, MD, PhD, said at the 2019 Gut Microbiota for Health World Summit.
“Each person experiences a meal differently through the filter of their gut microbiome, which helps explain individual differences in susceptibility to disease,” said Dr. Hazen of Cleveland Clinic. “In the future, our medicine cabinets will have drugs in them that not only affect us, but also target the microbial enzymes that affect levels of metabolites like TMAO.”
Trimethylamine N-oxide (TMAO) is produced by gut bacteria. High levels (in one study, approximately 6.2 micromolar) significantly increase the risk of major adverse cardiovascular events even after controlling for traditional demographic and clinical risk factors. Studies indicate that TMAO alters cholesterol and bile acid metabolism, upregulates inflammatory pathways, and promotes foam cell formation, all of which worsen atherosclerosis. In addition, TMAO increases clotting risk by enhancing platelet reactivity.
“Reducing the amount of animal products in one’s diet helps reduce TMAO levels,” said Dr. Hazen. Certain fish – mainly those found in deep, cold water, such as cod – are high in TMAO. However, a bigger culprit in the United States is red meat, which contains two major TMAO precursors – choline and carnitine. In a recent study, Dr. Hazen and his associates gave 113 healthy volunteers three isocaloric diets in random order based on red meat, white meat, or plant-based protein. After 4 weeks, eating the daily equivalent of 8 ounces of steak or two quarter-pound beef patties nearly tripled plasma TMAO levels (P less than .05) from baseline. The white meat and vegetarian diets showed no such effect.
Crucially, the effect of red meat was reversible – TMAO levels fell significantly within 4 weeks after participants stopped consuming red meat. Eating red meat low in saturated fat did not prevent TMAO levels from rising, Dr. Hazen noted at the meeting at the meeting sponsored by the American Gastroenterological Association and the European Society for Neurogastroenterology and Motility.
In a second study, Dr. Hazen and his associates identified a two-step process by which gut bacteria metabolize carnitine to TMAO. The second step was greatly enhanced in individuals who eat red meat, suggesting a possible therapeutic target. In a third study, they found that high TMAO levels in mice fell significantly with a single oral dose of a second-generation inhibitor of trimethylamine lyase, the enzyme used by gut bacteria to convert choline to TMAO. The inhibitory effect was irreversible, did not reduce the viability of commensal microorganisms, and significantly lowered platelet hyperreactivity and clot formation.
Such results are exciting, but “drugs for bugs” will exhibit varying effects depending on which gut species are present at baseline, Dr. Hazen explained. Investigators will need to understand and account for these differences before therapies for the microbiome can enter the clinic. For now, a blood test for TMAO is available and can help clinicians tailor their suggestions on what to eat.
Dr. Hazen disclosed a consulting relationship with Proctor & Gamble, royalties for patents from Proctor & Gamble, Cleveland Heart Lab, and Quest Diagnostics, and research support from AstraZeneca, Pfizer, Roche Diagnostics, and Proctor & Gamble.
MIAMI – Researchers are one step closer to developing “drugs for bugs” – agents that target the gut microbiome to prevent and treat cardiometabolic diseases, Stanley L. Hazen, MD, PhD, said at the 2019 Gut Microbiota for Health World Summit.
“Each person experiences a meal differently through the filter of their gut microbiome, which helps explain individual differences in susceptibility to disease,” said Dr. Hazen of Cleveland Clinic. “In the future, our medicine cabinets will have drugs in them that not only affect us, but also target the microbial enzymes that affect levels of metabolites like TMAO.”
Trimethylamine N-oxide (TMAO) is produced by gut bacteria. High levels (in one study, approximately 6.2 micromolar) significantly increase the risk of major adverse cardiovascular events even after controlling for traditional demographic and clinical risk factors. Studies indicate that TMAO alters cholesterol and bile acid metabolism, upregulates inflammatory pathways, and promotes foam cell formation, all of which worsen atherosclerosis. In addition, TMAO increases clotting risk by enhancing platelet reactivity.
“Reducing the amount of animal products in one’s diet helps reduce TMAO levels,” said Dr. Hazen. Certain fish – mainly those found in deep, cold water, such as cod – are high in TMAO. However, a bigger culprit in the United States is red meat, which contains two major TMAO precursors – choline and carnitine. In a recent study, Dr. Hazen and his associates gave 113 healthy volunteers three isocaloric diets in random order based on red meat, white meat, or plant-based protein. After 4 weeks, eating the daily equivalent of 8 ounces of steak or two quarter-pound beef patties nearly tripled plasma TMAO levels (P less than .05) from baseline. The white meat and vegetarian diets showed no such effect.
Crucially, the effect of red meat was reversible – TMAO levels fell significantly within 4 weeks after participants stopped consuming red meat. Eating red meat low in saturated fat did not prevent TMAO levels from rising, Dr. Hazen noted at the meeting at the meeting sponsored by the American Gastroenterological Association and the European Society for Neurogastroenterology and Motility.
In a second study, Dr. Hazen and his associates identified a two-step process by which gut bacteria metabolize carnitine to TMAO. The second step was greatly enhanced in individuals who eat red meat, suggesting a possible therapeutic target. In a third study, they found that high TMAO levels in mice fell significantly with a single oral dose of a second-generation inhibitor of trimethylamine lyase, the enzyme used by gut bacteria to convert choline to TMAO. The inhibitory effect was irreversible, did not reduce the viability of commensal microorganisms, and significantly lowered platelet hyperreactivity and clot formation.
Such results are exciting, but “drugs for bugs” will exhibit varying effects depending on which gut species are present at baseline, Dr. Hazen explained. Investigators will need to understand and account for these differences before therapies for the microbiome can enter the clinic. For now, a blood test for TMAO is available and can help clinicians tailor their suggestions on what to eat.
Dr. Hazen disclosed a consulting relationship with Proctor & Gamble, royalties for patents from Proctor & Gamble, Cleveland Heart Lab, and Quest Diagnostics, and research support from AstraZeneca, Pfizer, Roche Diagnostics, and Proctor & Gamble.
MIAMI – Researchers are one step closer to developing “drugs for bugs” – agents that target the gut microbiome to prevent and treat cardiometabolic diseases, Stanley L. Hazen, MD, PhD, said at the 2019 Gut Microbiota for Health World Summit.
“Each person experiences a meal differently through the filter of their gut microbiome, which helps explain individual differences in susceptibility to disease,” said Dr. Hazen of Cleveland Clinic. “In the future, our medicine cabinets will have drugs in them that not only affect us, but also target the microbial enzymes that affect levels of metabolites like TMAO.”
Trimethylamine N-oxide (TMAO) is produced by gut bacteria. High levels (in one study, approximately 6.2 micromolar) significantly increase the risk of major adverse cardiovascular events even after controlling for traditional demographic and clinical risk factors. Studies indicate that TMAO alters cholesterol and bile acid metabolism, upregulates inflammatory pathways, and promotes foam cell formation, all of which worsen atherosclerosis. In addition, TMAO increases clotting risk by enhancing platelet reactivity.
“Reducing the amount of animal products in one’s diet helps reduce TMAO levels,” said Dr. Hazen. Certain fish – mainly those found in deep, cold water, such as cod – are high in TMAO. However, a bigger culprit in the United States is red meat, which contains two major TMAO precursors – choline and carnitine. In a recent study, Dr. Hazen and his associates gave 113 healthy volunteers three isocaloric diets in random order based on red meat, white meat, or plant-based protein. After 4 weeks, eating the daily equivalent of 8 ounces of steak or two quarter-pound beef patties nearly tripled plasma TMAO levels (P less than .05) from baseline. The white meat and vegetarian diets showed no such effect.
Crucially, the effect of red meat was reversible – TMAO levels fell significantly within 4 weeks after participants stopped consuming red meat. Eating red meat low in saturated fat did not prevent TMAO levels from rising, Dr. Hazen noted at the meeting at the meeting sponsored by the American Gastroenterological Association and the European Society for Neurogastroenterology and Motility.
In a second study, Dr. Hazen and his associates identified a two-step process by which gut bacteria metabolize carnitine to TMAO. The second step was greatly enhanced in individuals who eat red meat, suggesting a possible therapeutic target. In a third study, they found that high TMAO levels in mice fell significantly with a single oral dose of a second-generation inhibitor of trimethylamine lyase, the enzyme used by gut bacteria to convert choline to TMAO. The inhibitory effect was irreversible, did not reduce the viability of commensal microorganisms, and significantly lowered platelet hyperreactivity and clot formation.
Such results are exciting, but “drugs for bugs” will exhibit varying effects depending on which gut species are present at baseline, Dr. Hazen explained. Investigators will need to understand and account for these differences before therapies for the microbiome can enter the clinic. For now, a blood test for TMAO is available and can help clinicians tailor their suggestions on what to eat.
Dr. Hazen disclosed a consulting relationship with Proctor & Gamble, royalties for patents from Proctor & Gamble, Cleveland Heart Lab, and Quest Diagnostics, and research support from AstraZeneca, Pfizer, Roche Diagnostics, and Proctor & Gamble.
REPORTING FROM GMFH 2019
AGA Clinical Practice Update: Switching between biologics and biosimilars in inflammatory bowel disease
Patients with inflammatory bowel disease (IBD) will soon have access to new biosimilars to infliximab, adalimumab, and other monoclonal antibodies, experts wrote in an American Gastroenterological Association clinical practice update.
“It is anticipated that biosimilars for IBD are here to stay,” wrote Laura E. Raffals, MD, of the Mayo Clinic in Rochester, Minn., and her associates in Clinical Gastroenterology and Hepatology. “Provided that the regulatory pathway remains rigorous and postmarketing surveillance is performed adequately, clinicians and patients can be reassured that these agents will provide the same well-described effectiveness for moderate to severe Crohn’s disease and ulcerative colitis, without new safety concerns.”
Evidence supports the use of biosimilars in IBD, but switching patients in stable remission on infliximab (Remicade) to a biosimilar, namely infliximab-dyyb (Inflectra), should remain a case-by-case choice, according to an AGA clinical practice update. Pending more safety data, the update’s authors recommended against nonmedical switches during pregnancy and urge special attention when considering whether to switch children.
Biologics have revolutionized IBD treatment, but at a steep price. As patents expire, companies have developed biosimilar agents that aim to conserve safety and efficacy at lower cost. Studies support this idea, although whether initiating or switching to biosimilars will save patients (versus hospitals or payers) money “remains to be seen,” the practice update states.
The FDA approval process for biosimilars is more rigorous than that for generics, but it skips the multiple phases of clinical trials required to approve reference biologics. Instead, the FDA requires robust evidence that the biosimilar has comparable structure, function, immunogenicity, animal toxicity, pharmacokinetics and pharmacodynamics, and clinical safety and efficacy in humans. Under U.S. law, a biosimilar cannot be FDA approved if its clinically active components differ from the reference product or it shows clinically meaningful differences in safety, potency, or purity.
So far, five biosimilars have been approved by the FDA for use in IBD, although not all are on the market yet: infliximab-dyyb (Inflectra), adalimumab-atta (Amjevita), infliximab-abda (Renflexis), adalimumab-adbm (Cyltezo), and infliximab-qbtx (Ixifi). Most postmarketing studies of their use involved patients on stable doses of Remicade who switched to biosimilar infliximab-dyyb (Inflectra).
The best known of these studies is the double-blind, randomized NOR-SWITCH trial, in which patients with Crohn’s disease, ulcerative colitis, spondyloarthritis, rheumatoid arthritis, psoriatic arthritis, or chronic plaque psoriasis on Remicade either continued it or switched to biosimilar infliximab-dyyb (Inflectra). At week 52, both safety and the likelihood of worsening disease activity were similar regardless of treatment randomization. The study was not powered to assess subgroup outcomes in Crohn’s disease or ulcerative colitis, the practice update notes.
More recently, the results of the 16-week SECURE trial also indicated that switching to infliximab-dyyb (Inflectra) was safe and well tolerated by patients with remitted IBD. However, the FDA has not yet designated any biosimilar as “interchangeable” with an approved biologic confirmed safe in multiple switches, the practice update notes. As a result, state laws prohibit patients from being switched to a biosimilar without notification. Both the NOR-SWITCH and SECURE trials were done in Europe.
Clinicians also must understand that antidrug antibodies to originator and biosimilar infliximab cross-react with each other, the experts emphasized. Switching patients with antibodies to Remicade or a biosimilar to the other product therefore risks an immediate hypersensitivity reaction, including life-threatening anaphylaxis.
The authors disclosed no external funding sources. One author disclosed ties to AbbVie, Janssen, Pfizer, Merck, Samsung Bioepis, and Amgen. The rest reported having no conflicts of interest.
SOURCE: Raffals LA et al. Clin Gastroenterol Hepatol. 2018 Sep 6. doi: 10.1016/j.cgh.2018.08.064.
Patients with inflammatory bowel disease (IBD) will soon have access to new biosimilars to infliximab, adalimumab, and other monoclonal antibodies, experts wrote in an American Gastroenterological Association clinical practice update.
“It is anticipated that biosimilars for IBD are here to stay,” wrote Laura E. Raffals, MD, of the Mayo Clinic in Rochester, Minn., and her associates in Clinical Gastroenterology and Hepatology. “Provided that the regulatory pathway remains rigorous and postmarketing surveillance is performed adequately, clinicians and patients can be reassured that these agents will provide the same well-described effectiveness for moderate to severe Crohn’s disease and ulcerative colitis, without new safety concerns.”
Evidence supports the use of biosimilars in IBD, but switching patients in stable remission on infliximab (Remicade) to a biosimilar, namely infliximab-dyyb (Inflectra), should remain a case-by-case choice, according to an AGA clinical practice update. Pending more safety data, the update’s authors recommended against nonmedical switches during pregnancy and urge special attention when considering whether to switch children.
Biologics have revolutionized IBD treatment, but at a steep price. As patents expire, companies have developed biosimilar agents that aim to conserve safety and efficacy at lower cost. Studies support this idea, although whether initiating or switching to biosimilars will save patients (versus hospitals or payers) money “remains to be seen,” the practice update states.
The FDA approval process for biosimilars is more rigorous than that for generics, but it skips the multiple phases of clinical trials required to approve reference biologics. Instead, the FDA requires robust evidence that the biosimilar has comparable structure, function, immunogenicity, animal toxicity, pharmacokinetics and pharmacodynamics, and clinical safety and efficacy in humans. Under U.S. law, a biosimilar cannot be FDA approved if its clinically active components differ from the reference product or it shows clinically meaningful differences in safety, potency, or purity.
So far, five biosimilars have been approved by the FDA for use in IBD, although not all are on the market yet: infliximab-dyyb (Inflectra), adalimumab-atta (Amjevita), infliximab-abda (Renflexis), adalimumab-adbm (Cyltezo), and infliximab-qbtx (Ixifi). Most postmarketing studies of their use involved patients on stable doses of Remicade who switched to biosimilar infliximab-dyyb (Inflectra).
The best known of these studies is the double-blind, randomized NOR-SWITCH trial, in which patients with Crohn’s disease, ulcerative colitis, spondyloarthritis, rheumatoid arthritis, psoriatic arthritis, or chronic plaque psoriasis on Remicade either continued it or switched to biosimilar infliximab-dyyb (Inflectra). At week 52, both safety and the likelihood of worsening disease activity were similar regardless of treatment randomization. The study was not powered to assess subgroup outcomes in Crohn’s disease or ulcerative colitis, the practice update notes.
More recently, the results of the 16-week SECURE trial also indicated that switching to infliximab-dyyb (Inflectra) was safe and well tolerated by patients with remitted IBD. However, the FDA has not yet designated any biosimilar as “interchangeable” with an approved biologic confirmed safe in multiple switches, the practice update notes. As a result, state laws prohibit patients from being switched to a biosimilar without notification. Both the NOR-SWITCH and SECURE trials were done in Europe.
Clinicians also must understand that antidrug antibodies to originator and biosimilar infliximab cross-react with each other, the experts emphasized. Switching patients with antibodies to Remicade or a biosimilar to the other product therefore risks an immediate hypersensitivity reaction, including life-threatening anaphylaxis.
The authors disclosed no external funding sources. One author disclosed ties to AbbVie, Janssen, Pfizer, Merck, Samsung Bioepis, and Amgen. The rest reported having no conflicts of interest.
SOURCE: Raffals LA et al. Clin Gastroenterol Hepatol. 2018 Sep 6. doi: 10.1016/j.cgh.2018.08.064.
Patients with inflammatory bowel disease (IBD) will soon have access to new biosimilars to infliximab, adalimumab, and other monoclonal antibodies, experts wrote in an American Gastroenterological Association clinical practice update.
“It is anticipated that biosimilars for IBD are here to stay,” wrote Laura E. Raffals, MD, of the Mayo Clinic in Rochester, Minn., and her associates in Clinical Gastroenterology and Hepatology. “Provided that the regulatory pathway remains rigorous and postmarketing surveillance is performed adequately, clinicians and patients can be reassured that these agents will provide the same well-described effectiveness for moderate to severe Crohn’s disease and ulcerative colitis, without new safety concerns.”
Evidence supports the use of biosimilars in IBD, but switching patients in stable remission on infliximab (Remicade) to a biosimilar, namely infliximab-dyyb (Inflectra), should remain a case-by-case choice, according to an AGA clinical practice update. Pending more safety data, the update’s authors recommended against nonmedical switches during pregnancy and urge special attention when considering whether to switch children.
Biologics have revolutionized IBD treatment, but at a steep price. As patents expire, companies have developed biosimilar agents that aim to conserve safety and efficacy at lower cost. Studies support this idea, although whether initiating or switching to biosimilars will save patients (versus hospitals or payers) money “remains to be seen,” the practice update states.
The FDA approval process for biosimilars is more rigorous than that for generics, but it skips the multiple phases of clinical trials required to approve reference biologics. Instead, the FDA requires robust evidence that the biosimilar has comparable structure, function, immunogenicity, animal toxicity, pharmacokinetics and pharmacodynamics, and clinical safety and efficacy in humans. Under U.S. law, a biosimilar cannot be FDA approved if its clinically active components differ from the reference product or it shows clinically meaningful differences in safety, potency, or purity.
So far, five biosimilars have been approved by the FDA for use in IBD, although not all are on the market yet: infliximab-dyyb (Inflectra), adalimumab-atta (Amjevita), infliximab-abda (Renflexis), adalimumab-adbm (Cyltezo), and infliximab-qbtx (Ixifi). Most postmarketing studies of their use involved patients on stable doses of Remicade who switched to biosimilar infliximab-dyyb (Inflectra).
The best known of these studies is the double-blind, randomized NOR-SWITCH trial, in which patients with Crohn’s disease, ulcerative colitis, spondyloarthritis, rheumatoid arthritis, psoriatic arthritis, or chronic plaque psoriasis on Remicade either continued it or switched to biosimilar infliximab-dyyb (Inflectra). At week 52, both safety and the likelihood of worsening disease activity were similar regardless of treatment randomization. The study was not powered to assess subgroup outcomes in Crohn’s disease or ulcerative colitis, the practice update notes.
More recently, the results of the 16-week SECURE trial also indicated that switching to infliximab-dyyb (Inflectra) was safe and well tolerated by patients with remitted IBD. However, the FDA has not yet designated any biosimilar as “interchangeable” with an approved biologic confirmed safe in multiple switches, the practice update notes. As a result, state laws prohibit patients from being switched to a biosimilar without notification. Both the NOR-SWITCH and SECURE trials were done in Europe.
Clinicians also must understand that antidrug antibodies to originator and biosimilar infliximab cross-react with each other, the experts emphasized. Switching patients with antibodies to Remicade or a biosimilar to the other product therefore risks an immediate hypersensitivity reaction, including life-threatening anaphylaxis.
The authors disclosed no external funding sources. One author disclosed ties to AbbVie, Janssen, Pfizer, Merck, Samsung Bioepis, and Amgen. The rest reported having no conflicts of interest.
SOURCE: Raffals LA et al. Clin Gastroenterol Hepatol. 2018 Sep 6. doi: 10.1016/j.cgh.2018.08.064.
FROM CLINICAL GASTROENTEROLOGY AND HEPATOLOGY
AGA publishes care pathway for IBD in pregnancy
Ideally, pregnant women with inflammatory bowel disease (IBD) should receive coordinated care from gastroenterologists and maternal-fetal medicine specialists, plus additional input from nutritionists, lactation counselors, and colorectal surgeons as needed, states a new report from the American Gastroenterological Association.
But in reality, these women often receive scant and conflicting advice from health care providers, writes Uma Mahadevan, MD, of the University of California, San Francisco, with her associates in Gastroenterology.
An “explosion” of new treatments in the past 15 years has given hope to many women with IBD who wish to be healthy enough to conceive, the experts noted. But in a recent AGA survey, more than 40% of obstetrician/gynecologist (OB/GYN) providers felt that women with IBD received inadequate information about pregnancy, compared with patients with other immune-mediated diseases. Strikingly, 94% of surveyed clinicians said they had patients stop taking their IBD medications during pregnancy because they feared harm to the fetus. In doing so, these patients actually risked greater disease activity, perinatal flares, and adverse pregnancy outcomes.
Therefore, the AGA, in partnership with the Crohn’s & Colitis Foundation, the Society for Maternal-Fetal Medicine, and Girls With Guts, crafted a standardized, evidence-based care pathway for health care providers from diverse disciplines who treat women with IBD in all stages of family planning. Its authors recommended that a maternal-fetal medicine specialist oversee obstetric care whenever possible. A gastroenterologist should continue IBD care by seeing the patient once during the first or second trimester and thereafter depending on IBD severity. The patient should receive a “clear and easily understandable consensus plan” for managing complex care during and after pregnancy, according to the pathway.
Aminosalicylates, biologics, and immunomodulators can be continued during pregnancy and delivery. Biologics have not shown teratogenicity in large studies, but monotherapy is preferred to reduce infection risk in infants. Clinicians should calculate weight-based doses according to prepregnancy weight. Doses can be tweaked to achieve minimal trough levels near delivery.
During pregnancy, patients should stop antidiarrheal therapy with loperamide and diphenoxylate when possible. Proinflammatory mediators are known to damage hippocampal neurogenesis and neuronal cytoarchitecture during brain development, so patients should understand the need for good inflammatory control during pregnancy. However, biologic therapy is preferred, and patients should only use corticosteroids adjunctively if needed for flares.
The usual indications guide the choice between a vaginal or cesarean delivery, the pathway states. Vaginal delivery often is possible for patients without active perineal disease, while cesarean is recommended for women with prior perineal surgery or active perineal disease or rectovaginal fistulas. The perineal area can be examined for active disease during the routine visit for group B streptococcus screening culture at 35-37 weeks’ gestation. For women who have had ileal-pouch anal anastomosis surgery, mode of delivery does not seem to affect pouch function, but cesarean delivery is thought to prevent anal sphincter injury and the accompanying risk of incontinence.
For ostomy patients, stretching of the abdominal wall during pregnancy can lead to stomal problems, such as displacement, enlargement, retraction, stenosis, and prolapse. A nutritionist can help ostomy patients avoid excess weight gain, and a colorectal surgeon and ostomy/wound nurse can help coordinate postpartum care. If cesarean delivery is needed, simply covering the ostomy with gauze sufficiently protects the operative field.
Since IBD increases the risk of venous thromboembolism, clinicians should consider prophylactic anticoagulation after cesarean delivery and during a hospitalization for IBD flares, according to the care pathway. Breastfeeding women can receive unfractionated heparin, low-molecular-weight heparin, or warfarin up to 3-6 weeks post partum, but they should not receive oral direct thrombin or factor Xa inhibitors.
In addition, most IBD medications are either undetectable in breast milk or are secreted at such low concentrations that they pose no known risk to infants. Therefore, patients can continue IBD medications after delivery – except methotrexate, which has not been sufficiently studied to assess its safety. Breastfeeding women with IBD should avoid using fenugreek to increase milk production, since it can cause diarrhea and bleeding.
Finally, infants should not receive live vaccines during the first 6 months after birth if their mothers received biologics besides certolizumab during the third trimester, the pathway notes. In the United States, this applies only to the oral rotavirus vaccine.
For more information about the care pathway and resources for your patients, visit IBDParenthoodProject.org.
SOURCE: Mahadevan U et al. Gastroenterology. 2019 Jan 15. doi: 10.1053/j.gastro.2018.12.022.
Ideally, pregnant women with inflammatory bowel disease (IBD) should receive coordinated care from gastroenterologists and maternal-fetal medicine specialists, plus additional input from nutritionists, lactation counselors, and colorectal surgeons as needed, states a new report from the American Gastroenterological Association.
But in reality, these women often receive scant and conflicting advice from health care providers, writes Uma Mahadevan, MD, of the University of California, San Francisco, with her associates in Gastroenterology.
An “explosion” of new treatments in the past 15 years has given hope to many women with IBD who wish to be healthy enough to conceive, the experts noted. But in a recent AGA survey, more than 40% of obstetrician/gynecologist (OB/GYN) providers felt that women with IBD received inadequate information about pregnancy, compared with patients with other immune-mediated diseases. Strikingly, 94% of surveyed clinicians said they had patients stop taking their IBD medications during pregnancy because they feared harm to the fetus. In doing so, these patients actually risked greater disease activity, perinatal flares, and adverse pregnancy outcomes.
Therefore, the AGA, in partnership with the Crohn’s & Colitis Foundation, the Society for Maternal-Fetal Medicine, and Girls With Guts, crafted a standardized, evidence-based care pathway for health care providers from diverse disciplines who treat women with IBD in all stages of family planning. Its authors recommended that a maternal-fetal medicine specialist oversee obstetric care whenever possible. A gastroenterologist should continue IBD care by seeing the patient once during the first or second trimester and thereafter depending on IBD severity. The patient should receive a “clear and easily understandable consensus plan” for managing complex care during and after pregnancy, according to the pathway.
Aminosalicylates, biologics, and immunomodulators can be continued during pregnancy and delivery. Biologics have not shown teratogenicity in large studies, but monotherapy is preferred to reduce infection risk in infants. Clinicians should calculate weight-based doses according to prepregnancy weight. Doses can be tweaked to achieve minimal trough levels near delivery.
During pregnancy, patients should stop antidiarrheal therapy with loperamide and diphenoxylate when possible. Proinflammatory mediators are known to damage hippocampal neurogenesis and neuronal cytoarchitecture during brain development, so patients should understand the need for good inflammatory control during pregnancy. However, biologic therapy is preferred, and patients should only use corticosteroids adjunctively if needed for flares.
The usual indications guide the choice between a vaginal or cesarean delivery, the pathway states. Vaginal delivery often is possible for patients without active perineal disease, while cesarean is recommended for women with prior perineal surgery or active perineal disease or rectovaginal fistulas. The perineal area can be examined for active disease during the routine visit for group B streptococcus screening culture at 35-37 weeks’ gestation. For women who have had ileal-pouch anal anastomosis surgery, mode of delivery does not seem to affect pouch function, but cesarean delivery is thought to prevent anal sphincter injury and the accompanying risk of incontinence.
For ostomy patients, stretching of the abdominal wall during pregnancy can lead to stomal problems, such as displacement, enlargement, retraction, stenosis, and prolapse. A nutritionist can help ostomy patients avoid excess weight gain, and a colorectal surgeon and ostomy/wound nurse can help coordinate postpartum care. If cesarean delivery is needed, simply covering the ostomy with gauze sufficiently protects the operative field.
Since IBD increases the risk of venous thromboembolism, clinicians should consider prophylactic anticoagulation after cesarean delivery and during a hospitalization for IBD flares, according to the care pathway. Breastfeeding women can receive unfractionated heparin, low-molecular-weight heparin, or warfarin up to 3-6 weeks post partum, but they should not receive oral direct thrombin or factor Xa inhibitors.
In addition, most IBD medications are either undetectable in breast milk or are secreted at such low concentrations that they pose no known risk to infants. Therefore, patients can continue IBD medications after delivery – except methotrexate, which has not been sufficiently studied to assess its safety. Breastfeeding women with IBD should avoid using fenugreek to increase milk production, since it can cause diarrhea and bleeding.
Finally, infants should not receive live vaccines during the first 6 months after birth if their mothers received biologics besides certolizumab during the third trimester, the pathway notes. In the United States, this applies only to the oral rotavirus vaccine.
For more information about the care pathway and resources for your patients, visit IBDParenthoodProject.org.
SOURCE: Mahadevan U et al. Gastroenterology. 2019 Jan 15. doi: 10.1053/j.gastro.2018.12.022.
Ideally, pregnant women with inflammatory bowel disease (IBD) should receive coordinated care from gastroenterologists and maternal-fetal medicine specialists, plus additional input from nutritionists, lactation counselors, and colorectal surgeons as needed, states a new report from the American Gastroenterological Association.
But in reality, these women often receive scant and conflicting advice from health care providers, writes Uma Mahadevan, MD, of the University of California, San Francisco, with her associates in Gastroenterology.
An “explosion” of new treatments in the past 15 years has given hope to many women with IBD who wish to be healthy enough to conceive, the experts noted. But in a recent AGA survey, more than 40% of obstetrician/gynecologist (OB/GYN) providers felt that women with IBD received inadequate information about pregnancy, compared with patients with other immune-mediated diseases. Strikingly, 94% of surveyed clinicians said they had patients stop taking their IBD medications during pregnancy because they feared harm to the fetus. In doing so, these patients actually risked greater disease activity, perinatal flares, and adverse pregnancy outcomes.
Therefore, the AGA, in partnership with the Crohn’s & Colitis Foundation, the Society for Maternal-Fetal Medicine, and Girls With Guts, crafted a standardized, evidence-based care pathway for health care providers from diverse disciplines who treat women with IBD in all stages of family planning. Its authors recommended that a maternal-fetal medicine specialist oversee obstetric care whenever possible. A gastroenterologist should continue IBD care by seeing the patient once during the first or second trimester and thereafter depending on IBD severity. The patient should receive a “clear and easily understandable consensus plan” for managing complex care during and after pregnancy, according to the pathway.
Aminosalicylates, biologics, and immunomodulators can be continued during pregnancy and delivery. Biologics have not shown teratogenicity in large studies, but monotherapy is preferred to reduce infection risk in infants. Clinicians should calculate weight-based doses according to prepregnancy weight. Doses can be tweaked to achieve minimal trough levels near delivery.
During pregnancy, patients should stop antidiarrheal therapy with loperamide and diphenoxylate when possible. Proinflammatory mediators are known to damage hippocampal neurogenesis and neuronal cytoarchitecture during brain development, so patients should understand the need for good inflammatory control during pregnancy. However, biologic therapy is preferred, and patients should only use corticosteroids adjunctively if needed for flares.
The usual indications guide the choice between a vaginal or cesarean delivery, the pathway states. Vaginal delivery often is possible for patients without active perineal disease, while cesarean is recommended for women with prior perineal surgery or active perineal disease or rectovaginal fistulas. The perineal area can be examined for active disease during the routine visit for group B streptococcus screening culture at 35-37 weeks’ gestation. For women who have had ileal-pouch anal anastomosis surgery, mode of delivery does not seem to affect pouch function, but cesarean delivery is thought to prevent anal sphincter injury and the accompanying risk of incontinence.
For ostomy patients, stretching of the abdominal wall during pregnancy can lead to stomal problems, such as displacement, enlargement, retraction, stenosis, and prolapse. A nutritionist can help ostomy patients avoid excess weight gain, and a colorectal surgeon and ostomy/wound nurse can help coordinate postpartum care. If cesarean delivery is needed, simply covering the ostomy with gauze sufficiently protects the operative field.
Since IBD increases the risk of venous thromboembolism, clinicians should consider prophylactic anticoagulation after cesarean delivery and during a hospitalization for IBD flares, according to the care pathway. Breastfeeding women can receive unfractionated heparin, low-molecular-weight heparin, or warfarin up to 3-6 weeks post partum, but they should not receive oral direct thrombin or factor Xa inhibitors.
In addition, most IBD medications are either undetectable in breast milk or are secreted at such low concentrations that they pose no known risk to infants. Therefore, patients can continue IBD medications after delivery – except methotrexate, which has not been sufficiently studied to assess its safety. Breastfeeding women with IBD should avoid using fenugreek to increase milk production, since it can cause diarrhea and bleeding.
Finally, infants should not receive live vaccines during the first 6 months after birth if their mothers received biologics besides certolizumab during the third trimester, the pathway notes. In the United States, this applies only to the oral rotavirus vaccine.
For more information about the care pathway and resources for your patients, visit IBDParenthoodProject.org.
SOURCE: Mahadevan U et al. Gastroenterology. 2019 Jan 15. doi: 10.1053/j.gastro.2018.12.022.
FROM THE AMERICAN GASTROENTEROLOGICAL ASSOCIATION
Western diet linked to lower microbiome diversity
MIAMI – Eating a Western diet correlated with significantly lower gut microbiome diversity in an observational study of 1,000 healthy men and women.
The chief culprits were fried foods, sodas, fatty sweets, processed meats, ready-cooked meals, and desserts, reported Valentin Partula, a PhD student at the Université Paris 13 Nord and his associates. The more often individuals reported consuming these, the fewer bacterial species were identified in their stool (P less than .05 for each association), the investigators wrote in a poster presented at the annual Gut Microbiota for Health World Summit.
Studies have linked decreased microbiota diversity with health conditions ranging from inflammatory bowel disease and colorectal cancer to diabetes mellitus. Obesity also is characterized by a less diverse microbiome and is linked to many of the same diseases, but the diversity (richness) of the gut microbiome appears to have more to do with diet than body mass index. However, interventional studies linking diet to microbiome shifts often have been small, narrow in scope, and short in duration, the researchers noted at the meeting sponsored by the American Gastroenterological Association and the European Society for Neurogastroenterology and Motility.
To help fill these gaps, they administered a 19-item food-frequency questionnaire to 1,000 healthy men and women in France who were 20-69 years old. Each food question had six possible responses, ranging from “at least twice a day” to “never.” For 862 of these men and women, the researchers also analyzed stool samples using 16S rRNA sequencing – a standard test for microbiome diversity. These sequencing results were analyzed in terms of both alpha diversity (the number of species within a sample, and the relative abundance of each) and beta diversity (the degree of dissimilarity among different individuals).
The most significant correlate of low alpha diversity (that is, a less diverse gut microbiome) was frequent consumption of fried foods, followed by sodas or sugary drinks, fatty sweet products, processed meats, ready-cooked meals, and desserts (P less than .05 for each). Conversely, raw fruits and fish each correlated with having a richer microbiome (P less than .05). Consuming eggs and raw and cooked vegetables also correlated with greater diversity, but these associations did not reach statistical significance.
In terms of beta diversity (uniqueness of the microbiome signature), the strongest correlates were fresh fruit, fried products, ready-cooked meals, and cheese. The finding for fresh fruit might be an effect of weighting but needs further study, the researchers said. Taken together, however, the findings “extend and support mechanistic arguments linking Western diet to altered microbiota composition,” they said.
Next, they looked at how specific foods correlated with specific bacterial taxa. Consuming more dairy correlated with a greater abundance of Streptococcus salivarius, which disrupts S. pyogenes biofilms in the pharynx and thus might help prevent bacterial pharyngitis. Eating raw fruits was tied to increases in Eubacterium eligens, a nonpathogenic bacterium whose role in the gut remains unclear. Finally, frequent cheese consumption was linked to lower abundance of Akkermansia muciniphila, a bacterium that is thought to benefit metabolic pathways and immune signaling.
For the same 846 individuals, the researchers performed 1hydrogen nuclear magnetic resonance metabolomic tests on plasma Carr-Purcell-Meiboom-Gill (CPMG)–pulse sequence and nuclear Overhauser enhancement spectroscopy (NOESY). Increased creatinine was associated with the highest number of bacterial taxa and might reflect effects on kidney function or trimethylamine N-oxide, they wrote. Greater microbiome diversity correlated with higher plasma levels of amino acids, proteins, creatinine, choline, glucose, and citrate. Lower diversity was tied to the presence of lipid-based metabolites, including ketones and esters.
The next step is to confirm the findings in a separate population and establish which of these associations are probably causal, the researchers wrote. “Mechanistic studies elucidating the metabolic capability of the organisms [also] are needed.”
No external funding sources or conflicts of interest were reported.
MIAMI – Eating a Western diet correlated with significantly lower gut microbiome diversity in an observational study of 1,000 healthy men and women.
The chief culprits were fried foods, sodas, fatty sweets, processed meats, ready-cooked meals, and desserts, reported Valentin Partula, a PhD student at the Université Paris 13 Nord and his associates. The more often individuals reported consuming these, the fewer bacterial species were identified in their stool (P less than .05 for each association), the investigators wrote in a poster presented at the annual Gut Microbiota for Health World Summit.
Studies have linked decreased microbiota diversity with health conditions ranging from inflammatory bowel disease and colorectal cancer to diabetes mellitus. Obesity also is characterized by a less diverse microbiome and is linked to many of the same diseases, but the diversity (richness) of the gut microbiome appears to have more to do with diet than body mass index. However, interventional studies linking diet to microbiome shifts often have been small, narrow in scope, and short in duration, the researchers noted at the meeting sponsored by the American Gastroenterological Association and the European Society for Neurogastroenterology and Motility.
To help fill these gaps, they administered a 19-item food-frequency questionnaire to 1,000 healthy men and women in France who were 20-69 years old. Each food question had six possible responses, ranging from “at least twice a day” to “never.” For 862 of these men and women, the researchers also analyzed stool samples using 16S rRNA sequencing – a standard test for microbiome diversity. These sequencing results were analyzed in terms of both alpha diversity (the number of species within a sample, and the relative abundance of each) and beta diversity (the degree of dissimilarity among different individuals).
The most significant correlate of low alpha diversity (that is, a less diverse gut microbiome) was frequent consumption of fried foods, followed by sodas or sugary drinks, fatty sweet products, processed meats, ready-cooked meals, and desserts (P less than .05 for each). Conversely, raw fruits and fish each correlated with having a richer microbiome (P less than .05). Consuming eggs and raw and cooked vegetables also correlated with greater diversity, but these associations did not reach statistical significance.
In terms of beta diversity (uniqueness of the microbiome signature), the strongest correlates were fresh fruit, fried products, ready-cooked meals, and cheese. The finding for fresh fruit might be an effect of weighting but needs further study, the researchers said. Taken together, however, the findings “extend and support mechanistic arguments linking Western diet to altered microbiota composition,” they said.
Next, they looked at how specific foods correlated with specific bacterial taxa. Consuming more dairy correlated with a greater abundance of Streptococcus salivarius, which disrupts S. pyogenes biofilms in the pharynx and thus might help prevent bacterial pharyngitis. Eating raw fruits was tied to increases in Eubacterium eligens, a nonpathogenic bacterium whose role in the gut remains unclear. Finally, frequent cheese consumption was linked to lower abundance of Akkermansia muciniphila, a bacterium that is thought to benefit metabolic pathways and immune signaling.
For the same 846 individuals, the researchers performed 1hydrogen nuclear magnetic resonance metabolomic tests on plasma Carr-Purcell-Meiboom-Gill (CPMG)–pulse sequence and nuclear Overhauser enhancement spectroscopy (NOESY). Increased creatinine was associated with the highest number of bacterial taxa and might reflect effects on kidney function or trimethylamine N-oxide, they wrote. Greater microbiome diversity correlated with higher plasma levels of amino acids, proteins, creatinine, choline, glucose, and citrate. Lower diversity was tied to the presence of lipid-based metabolites, including ketones and esters.
The next step is to confirm the findings in a separate population and establish which of these associations are probably causal, the researchers wrote. “Mechanistic studies elucidating the metabolic capability of the organisms [also] are needed.”
No external funding sources or conflicts of interest were reported.
MIAMI – Eating a Western diet correlated with significantly lower gut microbiome diversity in an observational study of 1,000 healthy men and women.
The chief culprits were fried foods, sodas, fatty sweets, processed meats, ready-cooked meals, and desserts, reported Valentin Partula, a PhD student at the Université Paris 13 Nord and his associates. The more often individuals reported consuming these, the fewer bacterial species were identified in their stool (P less than .05 for each association), the investigators wrote in a poster presented at the annual Gut Microbiota for Health World Summit.
Studies have linked decreased microbiota diversity with health conditions ranging from inflammatory bowel disease and colorectal cancer to diabetes mellitus. Obesity also is characterized by a less diverse microbiome and is linked to many of the same diseases, but the diversity (richness) of the gut microbiome appears to have more to do with diet than body mass index. However, interventional studies linking diet to microbiome shifts often have been small, narrow in scope, and short in duration, the researchers noted at the meeting sponsored by the American Gastroenterological Association and the European Society for Neurogastroenterology and Motility.
To help fill these gaps, they administered a 19-item food-frequency questionnaire to 1,000 healthy men and women in France who were 20-69 years old. Each food question had six possible responses, ranging from “at least twice a day” to “never.” For 862 of these men and women, the researchers also analyzed stool samples using 16S rRNA sequencing – a standard test for microbiome diversity. These sequencing results were analyzed in terms of both alpha diversity (the number of species within a sample, and the relative abundance of each) and beta diversity (the degree of dissimilarity among different individuals).
The most significant correlate of low alpha diversity (that is, a less diverse gut microbiome) was frequent consumption of fried foods, followed by sodas or sugary drinks, fatty sweet products, processed meats, ready-cooked meals, and desserts (P less than .05 for each). Conversely, raw fruits and fish each correlated with having a richer microbiome (P less than .05). Consuming eggs and raw and cooked vegetables also correlated with greater diversity, but these associations did not reach statistical significance.
In terms of beta diversity (uniqueness of the microbiome signature), the strongest correlates were fresh fruit, fried products, ready-cooked meals, and cheese. The finding for fresh fruit might be an effect of weighting but needs further study, the researchers said. Taken together, however, the findings “extend and support mechanistic arguments linking Western diet to altered microbiota composition,” they said.
Next, they looked at how specific foods correlated with specific bacterial taxa. Consuming more dairy correlated with a greater abundance of Streptococcus salivarius, which disrupts S. pyogenes biofilms in the pharynx and thus might help prevent bacterial pharyngitis. Eating raw fruits was tied to increases in Eubacterium eligens, a nonpathogenic bacterium whose role in the gut remains unclear. Finally, frequent cheese consumption was linked to lower abundance of Akkermansia muciniphila, a bacterium that is thought to benefit metabolic pathways and immune signaling.
For the same 846 individuals, the researchers performed 1hydrogen nuclear magnetic resonance metabolomic tests on plasma Carr-Purcell-Meiboom-Gill (CPMG)–pulse sequence and nuclear Overhauser enhancement spectroscopy (NOESY). Increased creatinine was associated with the highest number of bacterial taxa and might reflect effects on kidney function or trimethylamine N-oxide, they wrote. Greater microbiome diversity correlated with higher plasma levels of amino acids, proteins, creatinine, choline, glucose, and citrate. Lower diversity was tied to the presence of lipid-based metabolites, including ketones and esters.
The next step is to confirm the findings in a separate population and establish which of these associations are probably causal, the researchers wrote. “Mechanistic studies elucidating the metabolic capability of the organisms [also] are needed.”
No external funding sources or conflicts of interest were reported.
REPORTING FROM GMFH 2019
Hyperglycemia drives leaky gut syndrome, inflammation
MIAMI – Hyperglycemia increases intestinal permeability, which facilitates enteric infections and systemic inflammation, reported Christoph Thaiss, PhD.
The findings upend the old idea that intestinal barrier dysfunction leads to diabetes, Dr. Thaiss said during a plenary session at the annual Gut Microbiota for Health World Summit. Multiple mouse models link hyperglycemia to intestinal barrier dysfunction, and hemoglobin A1C (HbA1c) levels in humans “highly correlate with the influx of microbial molecules into the intestinal epithelium.”
Researchers often struggle to decide if apparent causes are really confounders or even downstream results (reverse causation). In the metabolic syndrome, patients are known to have increased intestinal permeability – so-called leaky gut – and microbes crossing the gastrointestinal epithelium have been found to cause both gut mucosal infections and chronic systemic inflammation. But because these mechanisms were poorly understood, some experts posited that intestinal barrier dysfunction induced pancreatic beta cell inflammation, insulin resistance, and diabetes.
To take a deeper dive, Dr. Thaiss and his associates at the University of Pennsylvania, Philadelphia started with a mouse model of morbid obesity. The mice had multiple systemic sites with microbial pattern recognition ligands, signifying microbial influx from the gut. They also had genetic signatures indicating a marked disruption of junctions between epithelial cells, compared with healthy controls.
The obese mice also were much more susceptible to enteric infections with Citrobacter rodentium (a Salmonella analog), but obesity itself did not drive this risk, Dr. Thaiss explained. In fact, two different murine models of nonobese type 1 diabetes mellitus showed “leaky” intestinal epithelial adherence junctions, heightened susceptibility to C. rodentium infection, and showed systemic pathogen spread. Ribosomal DNA sequencing showed that these hyperglycemic (diabetic) mice had shifts in their gut microbiomes; however, translocating the altered microbiota to normal mice did not make them more susceptible to enteric infections or systemic inflammation.
Based on these findings, the researchers hypothesized that hyperglycemia itself drove susceptibility to enteric infections. They confirmed this by administering insulin to the mice with type 1 diabetes, which restored intestinal epithelial adherence junctions and stopped the systemic spread of pathogens. In vitro, exposing intestinal epithelial cells to glucose-induced barrier dysfunctions that increased over time and with higher glucose concentrations. RNA sequencing demonstrated that hyperglycemia markedly changed expression of genes that encode proteins that regulate intestinal barrier function. Moreover, hyperglycemic mice lacking the bidirectional glucose transporter GLUT2 showed no intestinal barrier dysfunction and were not susceptible to C. rodentium infection and systemic spread.
Finally, the investigators studied more than 30 clinical measures and microbial products in the systemic circulation of 27 healthy human volunteers. “Of all the variables we measured, HbA1c showed the strongest correlation with the influx of microbial molecules,” said Dr. Thaiss. Serum HbA1c correlated highly (P = .008) with levels of toll-like receptor 4, an indicator of systemic pathogens, but not with body mass index (P = .76).
The findings in humans confirm those in mice and indicate that hyperglycemia is a direct cause of intestinal barrier dysfunction and susceptibility to enteric infection, Dr. Thaiss said, adding that the systemic influx of microbial products might explain the wide range of otherwise unrelated inflammatory conditions seen in patients with metabolic syndrome. Future studies of therapies for enteric infection and systemic inflammation might focus on glucose as a modifier of intestinal barrier function.
These findings, reported at the meeting sponsored by the American Gastroenterological Association and the European Society for Neurogastroenterology and Motility, were also published in Science.
The work was supported by a Boehringer Ingelheim Funds PhD fellowship, the Leona M. and Harry B. Helmsley Charitable Trust, the Adelis Foundation, the Gurwin Family Fund for Scientific Research, the Crown Endowment Fund for Immunological Research, and others. Dr. Thaiss and his coinvestigators reported having no conflicts of interest.
SOURCE: Thaiss CA et al. Science. 2018;359(6382):1376-83.
MIAMI – Hyperglycemia increases intestinal permeability, which facilitates enteric infections and systemic inflammation, reported Christoph Thaiss, PhD.
The findings upend the old idea that intestinal barrier dysfunction leads to diabetes, Dr. Thaiss said during a plenary session at the annual Gut Microbiota for Health World Summit. Multiple mouse models link hyperglycemia to intestinal barrier dysfunction, and hemoglobin A1C (HbA1c) levels in humans “highly correlate with the influx of microbial molecules into the intestinal epithelium.”
Researchers often struggle to decide if apparent causes are really confounders or even downstream results (reverse causation). In the metabolic syndrome, patients are known to have increased intestinal permeability – so-called leaky gut – and microbes crossing the gastrointestinal epithelium have been found to cause both gut mucosal infections and chronic systemic inflammation. But because these mechanisms were poorly understood, some experts posited that intestinal barrier dysfunction induced pancreatic beta cell inflammation, insulin resistance, and diabetes.
To take a deeper dive, Dr. Thaiss and his associates at the University of Pennsylvania, Philadelphia started with a mouse model of morbid obesity. The mice had multiple systemic sites with microbial pattern recognition ligands, signifying microbial influx from the gut. They also had genetic signatures indicating a marked disruption of junctions between epithelial cells, compared with healthy controls.
The obese mice also were much more susceptible to enteric infections with Citrobacter rodentium (a Salmonella analog), but obesity itself did not drive this risk, Dr. Thaiss explained. In fact, two different murine models of nonobese type 1 diabetes mellitus showed “leaky” intestinal epithelial adherence junctions, heightened susceptibility to C. rodentium infection, and showed systemic pathogen spread. Ribosomal DNA sequencing showed that these hyperglycemic (diabetic) mice had shifts in their gut microbiomes; however, translocating the altered microbiota to normal mice did not make them more susceptible to enteric infections or systemic inflammation.
Based on these findings, the researchers hypothesized that hyperglycemia itself drove susceptibility to enteric infections. They confirmed this by administering insulin to the mice with type 1 diabetes, which restored intestinal epithelial adherence junctions and stopped the systemic spread of pathogens. In vitro, exposing intestinal epithelial cells to glucose-induced barrier dysfunctions that increased over time and with higher glucose concentrations. RNA sequencing demonstrated that hyperglycemia markedly changed expression of genes that encode proteins that regulate intestinal barrier function. Moreover, hyperglycemic mice lacking the bidirectional glucose transporter GLUT2 showed no intestinal barrier dysfunction and were not susceptible to C. rodentium infection and systemic spread.
Finally, the investigators studied more than 30 clinical measures and microbial products in the systemic circulation of 27 healthy human volunteers. “Of all the variables we measured, HbA1c showed the strongest correlation with the influx of microbial molecules,” said Dr. Thaiss. Serum HbA1c correlated highly (P = .008) with levels of toll-like receptor 4, an indicator of systemic pathogens, but not with body mass index (P = .76).
The findings in humans confirm those in mice and indicate that hyperglycemia is a direct cause of intestinal barrier dysfunction and susceptibility to enteric infection, Dr. Thaiss said, adding that the systemic influx of microbial products might explain the wide range of otherwise unrelated inflammatory conditions seen in patients with metabolic syndrome. Future studies of therapies for enteric infection and systemic inflammation might focus on glucose as a modifier of intestinal barrier function.
These findings, reported at the meeting sponsored by the American Gastroenterological Association and the European Society for Neurogastroenterology and Motility, were also published in Science.
The work was supported by a Boehringer Ingelheim Funds PhD fellowship, the Leona M. and Harry B. Helmsley Charitable Trust, the Adelis Foundation, the Gurwin Family Fund for Scientific Research, the Crown Endowment Fund for Immunological Research, and others. Dr. Thaiss and his coinvestigators reported having no conflicts of interest.
SOURCE: Thaiss CA et al. Science. 2018;359(6382):1376-83.
MIAMI – Hyperglycemia increases intestinal permeability, which facilitates enteric infections and systemic inflammation, reported Christoph Thaiss, PhD.
The findings upend the old idea that intestinal barrier dysfunction leads to diabetes, Dr. Thaiss said during a plenary session at the annual Gut Microbiota for Health World Summit. Multiple mouse models link hyperglycemia to intestinal barrier dysfunction, and hemoglobin A1C (HbA1c) levels in humans “highly correlate with the influx of microbial molecules into the intestinal epithelium.”
Researchers often struggle to decide if apparent causes are really confounders or even downstream results (reverse causation). In the metabolic syndrome, patients are known to have increased intestinal permeability – so-called leaky gut – and microbes crossing the gastrointestinal epithelium have been found to cause both gut mucosal infections and chronic systemic inflammation. But because these mechanisms were poorly understood, some experts posited that intestinal barrier dysfunction induced pancreatic beta cell inflammation, insulin resistance, and diabetes.
To take a deeper dive, Dr. Thaiss and his associates at the University of Pennsylvania, Philadelphia started with a mouse model of morbid obesity. The mice had multiple systemic sites with microbial pattern recognition ligands, signifying microbial influx from the gut. They also had genetic signatures indicating a marked disruption of junctions between epithelial cells, compared with healthy controls.
The obese mice also were much more susceptible to enteric infections with Citrobacter rodentium (a Salmonella analog), but obesity itself did not drive this risk, Dr. Thaiss explained. In fact, two different murine models of nonobese type 1 diabetes mellitus showed “leaky” intestinal epithelial adherence junctions, heightened susceptibility to C. rodentium infection, and showed systemic pathogen spread. Ribosomal DNA sequencing showed that these hyperglycemic (diabetic) mice had shifts in their gut microbiomes; however, translocating the altered microbiota to normal mice did not make them more susceptible to enteric infections or systemic inflammation.
Based on these findings, the researchers hypothesized that hyperglycemia itself drove susceptibility to enteric infections. They confirmed this by administering insulin to the mice with type 1 diabetes, which restored intestinal epithelial adherence junctions and stopped the systemic spread of pathogens. In vitro, exposing intestinal epithelial cells to glucose-induced barrier dysfunctions that increased over time and with higher glucose concentrations. RNA sequencing demonstrated that hyperglycemia markedly changed expression of genes that encode proteins that regulate intestinal barrier function. Moreover, hyperglycemic mice lacking the bidirectional glucose transporter GLUT2 showed no intestinal barrier dysfunction and were not susceptible to C. rodentium infection and systemic spread.
Finally, the investigators studied more than 30 clinical measures and microbial products in the systemic circulation of 27 healthy human volunteers. “Of all the variables we measured, HbA1c showed the strongest correlation with the influx of microbial molecules,” said Dr. Thaiss. Serum HbA1c correlated highly (P = .008) with levels of toll-like receptor 4, an indicator of systemic pathogens, but not with body mass index (P = .76).
The findings in humans confirm those in mice and indicate that hyperglycemia is a direct cause of intestinal barrier dysfunction and susceptibility to enteric infection, Dr. Thaiss said, adding that the systemic influx of microbial products might explain the wide range of otherwise unrelated inflammatory conditions seen in patients with metabolic syndrome. Future studies of therapies for enteric infection and systemic inflammation might focus on glucose as a modifier of intestinal barrier function.
These findings, reported at the meeting sponsored by the American Gastroenterological Association and the European Society for Neurogastroenterology and Motility, were also published in Science.
The work was supported by a Boehringer Ingelheim Funds PhD fellowship, the Leona M. and Harry B. Helmsley Charitable Trust, the Adelis Foundation, the Gurwin Family Fund for Scientific Research, the Crown Endowment Fund for Immunological Research, and others. Dr. Thaiss and his coinvestigators reported having no conflicts of interest.
SOURCE: Thaiss CA et al. Science. 2018;359(6382):1376-83.
REPORTING FROM GMFH 2019
Study eyes biomarkers of regorafenib response in hepatocellular carcinoma
.
“In the absence of established or predefined biomarkers for regorafenib, we performed a broad exploratory biomarker analyses at the DNA, RNA, and protein level that represents a much more comprehensive approach than previous studies of regorafenib or sorafenib,” wrote Michael Teufel, PhD, of Bayer Healthcare Pharmaceuticals in Whippany, N.J., and his associates. The preplanned, retrospective analysis of data from the phase 3 RESOURCE trial was reported in Gastroenterology.
The randomized trial included 567 patients whose hepatocellular carcinoma had progressed on sorafenib. Regorafenib significantly outperformed placebo with regard to overall survival (OS). Dr. Teufel and his associates performed next-generation sequencing on 17 archived tumor samples containing sufficient tissue (all from regorafenib recipients). They also performed immune profiling on 46 tumor samples (32 from regorafenib recipients and 14 from placebo recipients), protein analysis on 499 plasma samples (332 from regorafenib recipients and 167 from placebo recipients), and microRNA analysis on 343 plasma samples (234 regorafenib recipients and 109 placebo recipients).
Among 266 proteins tested, decreased levels of 5 proteins correlated with significantly longer OS on regorafenib therapy. These proteins are involved in inflammation or hepatocellular carcinogenesis, the researchers noted. Importantly, none were associated with survival independent of treatment. These five proteins included angiopoietin 1 (hazard ratio for OS, 0.53; 95% confidence interval, 0.38-0.73), cystatin B (hazard ratio, 0.47; 95% CI, 0.34-0.64); the latency-associated peptide of transforming growth factor beta (HR, 0.46; 95% CI, 0.33-0.64), oxidized low-density lipoprotein receptor 1 (HR, 0.54; 95% CI, 0.41-0.72), and C-C motif chemokine ligand 3 (HR, 0.54; 95% CI, 0.39-0.74).
Additionally, baseline concentrations of 47 of the 266 proteins correlated with a time to progression (TPP) benefit on regorafenib therapy (adjusted P less than or equal to .05 for each). The 47 proteins included all 5 that predicted an OS benefit. All but two proteins (calbindin and gelsolin) showed the same directional effect as for OS (that is, low expression predicted response).
Nine plasma microRNA’s levels correlated with improved OS on regorafenib (adjusted P less than or equal to .05): MIR30A, MIR122, MIR125B, MIR200A, MIR374B, MIR15B, MIR107, MIR320, and MIR645. Notably, expression was linked to longer OS specifically among patients with the Hoshida S3 subtype of hepatocellular carcinoma. Next-generation sequencing of tumor samples also identified 49 variants in 27 oncogenes or tumor-suppressor genes. Mutations in CTNNB1 were found in 3 of 10 patients who progressed on regorafenib, and VEGFA amplification was found in 1 of 7 regorafenib responders.
“Thus far, rational biomarker selection has been unsuccessful in identifying predictive markers for regorafenib in colorectal cancer and gastrointestinal stromal tumors,” the researchers commented. “The broader approach used in this study is not only biologically warranted considering the heterogeneity of hepatocellular carcinoma tumors, but is also needed due to the multiple targets and pathways affected by MKIs such as regorafenib. Levels of these circulating biomarkers and genetic features of tumors might be used to identify patients with hepatocellular carcinoma most likely to respond to regorafenib.”
Bayer funded the study, provided the study drug, and was involved in all aspects of the study. Dr. Teufel and three coinvestigators are Bayer employees. Dr. Teufel and two coinvestigators own stock in Bayer. Three other coinvestigators disclosed ties to Bayer and other pharmaceutical companies.
SOURCE: Teufel M et al. Gastroenterology. 2019 Jan 30. doi: 10.1053/j.gastro.2019.01.261.
.
“In the absence of established or predefined biomarkers for regorafenib, we performed a broad exploratory biomarker analyses at the DNA, RNA, and protein level that represents a much more comprehensive approach than previous studies of regorafenib or sorafenib,” wrote Michael Teufel, PhD, of Bayer Healthcare Pharmaceuticals in Whippany, N.J., and his associates. The preplanned, retrospective analysis of data from the phase 3 RESOURCE trial was reported in Gastroenterology.
The randomized trial included 567 patients whose hepatocellular carcinoma had progressed on sorafenib. Regorafenib significantly outperformed placebo with regard to overall survival (OS). Dr. Teufel and his associates performed next-generation sequencing on 17 archived tumor samples containing sufficient tissue (all from regorafenib recipients). They also performed immune profiling on 46 tumor samples (32 from regorafenib recipients and 14 from placebo recipients), protein analysis on 499 plasma samples (332 from regorafenib recipients and 167 from placebo recipients), and microRNA analysis on 343 plasma samples (234 regorafenib recipients and 109 placebo recipients).
Among 266 proteins tested, decreased levels of 5 proteins correlated with significantly longer OS on regorafenib therapy. These proteins are involved in inflammation or hepatocellular carcinogenesis, the researchers noted. Importantly, none were associated with survival independent of treatment. These five proteins included angiopoietin 1 (hazard ratio for OS, 0.53; 95% confidence interval, 0.38-0.73), cystatin B (hazard ratio, 0.47; 95% CI, 0.34-0.64); the latency-associated peptide of transforming growth factor beta (HR, 0.46; 95% CI, 0.33-0.64), oxidized low-density lipoprotein receptor 1 (HR, 0.54; 95% CI, 0.41-0.72), and C-C motif chemokine ligand 3 (HR, 0.54; 95% CI, 0.39-0.74).
Additionally, baseline concentrations of 47 of the 266 proteins correlated with a time to progression (TPP) benefit on regorafenib therapy (adjusted P less than or equal to .05 for each). The 47 proteins included all 5 that predicted an OS benefit. All but two proteins (calbindin and gelsolin) showed the same directional effect as for OS (that is, low expression predicted response).
Nine plasma microRNA’s levels correlated with improved OS on regorafenib (adjusted P less than or equal to .05): MIR30A, MIR122, MIR125B, MIR200A, MIR374B, MIR15B, MIR107, MIR320, and MIR645. Notably, expression was linked to longer OS specifically among patients with the Hoshida S3 subtype of hepatocellular carcinoma. Next-generation sequencing of tumor samples also identified 49 variants in 27 oncogenes or tumor-suppressor genes. Mutations in CTNNB1 were found in 3 of 10 patients who progressed on regorafenib, and VEGFA amplification was found in 1 of 7 regorafenib responders.
“Thus far, rational biomarker selection has been unsuccessful in identifying predictive markers for regorafenib in colorectal cancer and gastrointestinal stromal tumors,” the researchers commented. “The broader approach used in this study is not only biologically warranted considering the heterogeneity of hepatocellular carcinoma tumors, but is also needed due to the multiple targets and pathways affected by MKIs such as regorafenib. Levels of these circulating biomarkers and genetic features of tumors might be used to identify patients with hepatocellular carcinoma most likely to respond to regorafenib.”
Bayer funded the study, provided the study drug, and was involved in all aspects of the study. Dr. Teufel and three coinvestigators are Bayer employees. Dr. Teufel and two coinvestigators own stock in Bayer. Three other coinvestigators disclosed ties to Bayer and other pharmaceutical companies.
SOURCE: Teufel M et al. Gastroenterology. 2019 Jan 30. doi: 10.1053/j.gastro.2019.01.261.
.
“In the absence of established or predefined biomarkers for regorafenib, we performed a broad exploratory biomarker analyses at the DNA, RNA, and protein level that represents a much more comprehensive approach than previous studies of regorafenib or sorafenib,” wrote Michael Teufel, PhD, of Bayer Healthcare Pharmaceuticals in Whippany, N.J., and his associates. The preplanned, retrospective analysis of data from the phase 3 RESOURCE trial was reported in Gastroenterology.
The randomized trial included 567 patients whose hepatocellular carcinoma had progressed on sorafenib. Regorafenib significantly outperformed placebo with regard to overall survival (OS). Dr. Teufel and his associates performed next-generation sequencing on 17 archived tumor samples containing sufficient tissue (all from regorafenib recipients). They also performed immune profiling on 46 tumor samples (32 from regorafenib recipients and 14 from placebo recipients), protein analysis on 499 plasma samples (332 from regorafenib recipients and 167 from placebo recipients), and microRNA analysis on 343 plasma samples (234 regorafenib recipients and 109 placebo recipients).
Among 266 proteins tested, decreased levels of 5 proteins correlated with significantly longer OS on regorafenib therapy. These proteins are involved in inflammation or hepatocellular carcinogenesis, the researchers noted. Importantly, none were associated with survival independent of treatment. These five proteins included angiopoietin 1 (hazard ratio for OS, 0.53; 95% confidence interval, 0.38-0.73), cystatin B (hazard ratio, 0.47; 95% CI, 0.34-0.64); the latency-associated peptide of transforming growth factor beta (HR, 0.46; 95% CI, 0.33-0.64), oxidized low-density lipoprotein receptor 1 (HR, 0.54; 95% CI, 0.41-0.72), and C-C motif chemokine ligand 3 (HR, 0.54; 95% CI, 0.39-0.74).
Additionally, baseline concentrations of 47 of the 266 proteins correlated with a time to progression (TPP) benefit on regorafenib therapy (adjusted P less than or equal to .05 for each). The 47 proteins included all 5 that predicted an OS benefit. All but two proteins (calbindin and gelsolin) showed the same directional effect as for OS (that is, low expression predicted response).
Nine plasma microRNA’s levels correlated with improved OS on regorafenib (adjusted P less than or equal to .05): MIR30A, MIR122, MIR125B, MIR200A, MIR374B, MIR15B, MIR107, MIR320, and MIR645. Notably, expression was linked to longer OS specifically among patients with the Hoshida S3 subtype of hepatocellular carcinoma. Next-generation sequencing of tumor samples also identified 49 variants in 27 oncogenes or tumor-suppressor genes. Mutations in CTNNB1 were found in 3 of 10 patients who progressed on regorafenib, and VEGFA amplification was found in 1 of 7 regorafenib responders.
“Thus far, rational biomarker selection has been unsuccessful in identifying predictive markers for regorafenib in colorectal cancer and gastrointestinal stromal tumors,” the researchers commented. “The broader approach used in this study is not only biologically warranted considering the heterogeneity of hepatocellular carcinoma tumors, but is also needed due to the multiple targets and pathways affected by MKIs such as regorafenib. Levels of these circulating biomarkers and genetic features of tumors might be used to identify patients with hepatocellular carcinoma most likely to respond to regorafenib.”
Bayer funded the study, provided the study drug, and was involved in all aspects of the study. Dr. Teufel and three coinvestigators are Bayer employees. Dr. Teufel and two coinvestigators own stock in Bayer. Three other coinvestigators disclosed ties to Bayer and other pharmaceutical companies.
SOURCE: Teufel M et al. Gastroenterology. 2019 Jan 30. doi: 10.1053/j.gastro.2019.01.261.
FROM GASTROENTEROLOGY
Mucosal impedance contour rapidly distinguished GERD, non-GERD, and eosinophilic esophagitis
.
Source: American Gastroenterological Association
Each group showed a significantly different (P less than .01) pattern of mucosal impedance (MI), or disruption of mucosal integrity, along the esophageal axis, wrote Dhyanesh A. Patel, MD, of Vanderbilt University Medical Center in Nashville, Tenn., and his associates. Patients without GERD had higher MI values along all esophageal segments, while GERD was characterized by below-normal values in the distal esophagus only, and eosinophilic esophagitis led to low values throughout the esophagus.
The findings were validated in a separate patient cohort, and the only reported adverse event was an episode of mild chest pain. “This contour heatmap could easily be employed to establish a diagnosis during endoscopy, independent of biopsy or pH monitoring,” the investigators wrote in Gastroenterology. They cautioned that the balloon catheter cannot be safely used in patients with severe fibrostenotic disease.
Current definitive diagnostics for GERD leave much to be desired. Transnasal probes are imprecise and uncomfortable, and they can be insensitive if discomfort causes patients to vary normal activity or skip meals. Wireless ambulatory pH monitoring is more tolerable but unreliable and measures only acidity of refluxed material at a single point along the esophagus. These tests also “fail to account for day-to-day variability of reflux, as they only provide a 24- to 48-hour snapshot of a disease process that is chronic in nature,” the researchers wrote. Eosinophilic esophagitis is becoming more common and usually requires proximal and distal biopsies for diagnosis.
Mucosal impedance contour pattern testing is based on the fact that both GERD and eosinophilic esophagitis involve increased distance between esophageal epithelial cells. The amount of intercellular dilatation correlates inversely with MI values. In proof-of-concept studies, individuals with GERD, non-GERD, eosinophilic esophagitis, and achalasia had distinct MI patterns. However, these studies tested a single-channel catheter system that took only point measurements and was subject to interoperator variability. To improve on this concept, Dr. Patel and his associates mounted radial and axial sensors on a balloon catheter to measure MI at 180-degree intervals along a 10-cm esophageal segment.
They tested the new device prospectively in 69 patients undergoing esophagogastroduodenoscopy with or without pH monitoring (which was used as the standard). In all, 24 patients had GERD, 21 had eosinophilic esophagitis, and 24 had normal findings. By using the intercept and slope of the balloon MI measurements, the researchers detected GERD with an area under the receiver operating characteristic curve (AUC) of 0.67, eosinophilic esophagitis with an AUC of 0.84, and non-GERD with an AUC of 0.83.
These findings held up in a separate validation cohort of 36 patients (28 with GERD and eight with eosinophilic esophagitis) from three tertiary care centers. The probability of eosinophilic esophagitis was highest in patients with low distal MI values (that is, a low intercept) and a low slope (showing that MI values remained low proximally). A low distal MI intercept with a steeper positive slope suggested GERD, while a higher distal MI intercept with a steep slope signified non-GERD.
The system “potentially obviates the need for 24- to 48-hour ambulatory wireless pH monitoring or esophageal biopsies for histopathology,” the researchers concluded. “This can help reduce diagnostic and treatment latency and might allow for monitoring disease activity over time.”
The National Institutes of Health funded the external validation analysis. Diversatek Healthcare, which patented the device together with Vanderbilt University, gave research funding to four coinvestigators, including the senior author. Dr. Patel and the other five coinvestigators reported having no conflicts of interest.
SOURCE: Patel DA et al. Gastroenterology. 2019 Jan 31. doi: 10.1053/j.gastro.2019.01.253.
Evaluating esophageal disorders such as GERD or eosinophilic esophagitis can be time consuming for patients in clinical practice and requires multiple visits to complete testing and obtain results. Other than visualizing complications of reflux such as erosive esophagitis or Barrett’s esophagus, there has been no immediate option to diagnose GERD in standard practice during routine endoscopy. Furthermore, the decision to pursue long-term medication or surgery for GERD relies on a brief pH assessment to be truly representative of a patient’s everyday symptoms. Follow-up of eosinophilic esophagitis requires repeated upper endoscopies with biopsies after every incremental change in medication or diet, which unsurprisingly, can reduce compliance with ongoing management for what is often a readily treatable condition.
Both GERD and eosinophilic esophagitis can be characterized by changes in esophageal mucosal impedance. Rather than directly measuring the pH or eosinophil counts, Dr. Patel and associates prospectively validated the diagnostic test performance of an add-on endoscopic mucosal impedance device that might enable the gastroenterologist to rule out GERD or rule in eosinophilic esophagitis during the index endoscopy with reasonable accuracy (AUC above 0.8 to rule out GERD or rule in eosinophilic esophagitis) while adding 2-3 minutes of procedure time. One patient was admitted for chest pain after use of the device but was discharged without complication, and the authors caution against use in severe fibrostenotic disease.
While work to refine a clinical prediction model with this technology is ongoing, the promise of diagnosing and following common esophageal conditions of GERD and eosinophilic esophagitis during endoscopy would have clear value in expediting care and enhancing compliance with treatment.
Eric D. Shah, MD, MBA, is assistant professor of medicine, director of gastrointestinal motility, esophageal, and swallowing disorders center, Geisel School of Medicine, Dartmouth College, Hanover, N.H. He has no disclosures.
Evaluating esophageal disorders such as GERD or eosinophilic esophagitis can be time consuming for patients in clinical practice and requires multiple visits to complete testing and obtain results. Other than visualizing complications of reflux such as erosive esophagitis or Barrett’s esophagus, there has been no immediate option to diagnose GERD in standard practice during routine endoscopy. Furthermore, the decision to pursue long-term medication or surgery for GERD relies on a brief pH assessment to be truly representative of a patient’s everyday symptoms. Follow-up of eosinophilic esophagitis requires repeated upper endoscopies with biopsies after every incremental change in medication or diet, which unsurprisingly, can reduce compliance with ongoing management for what is often a readily treatable condition.
Both GERD and eosinophilic esophagitis can be characterized by changes in esophageal mucosal impedance. Rather than directly measuring the pH or eosinophil counts, Dr. Patel and associates prospectively validated the diagnostic test performance of an add-on endoscopic mucosal impedance device that might enable the gastroenterologist to rule out GERD or rule in eosinophilic esophagitis during the index endoscopy with reasonable accuracy (AUC above 0.8 to rule out GERD or rule in eosinophilic esophagitis) while adding 2-3 minutes of procedure time. One patient was admitted for chest pain after use of the device but was discharged without complication, and the authors caution against use in severe fibrostenotic disease.
While work to refine a clinical prediction model with this technology is ongoing, the promise of diagnosing and following common esophageal conditions of GERD and eosinophilic esophagitis during endoscopy would have clear value in expediting care and enhancing compliance with treatment.
Eric D. Shah, MD, MBA, is assistant professor of medicine, director of gastrointestinal motility, esophageal, and swallowing disorders center, Geisel School of Medicine, Dartmouth College, Hanover, N.H. He has no disclosures.
Evaluating esophageal disorders such as GERD or eosinophilic esophagitis can be time consuming for patients in clinical practice and requires multiple visits to complete testing and obtain results. Other than visualizing complications of reflux such as erosive esophagitis or Barrett’s esophagus, there has been no immediate option to diagnose GERD in standard practice during routine endoscopy. Furthermore, the decision to pursue long-term medication or surgery for GERD relies on a brief pH assessment to be truly representative of a patient’s everyday symptoms. Follow-up of eosinophilic esophagitis requires repeated upper endoscopies with biopsies after every incremental change in medication or diet, which unsurprisingly, can reduce compliance with ongoing management for what is often a readily treatable condition.
Both GERD and eosinophilic esophagitis can be characterized by changes in esophageal mucosal impedance. Rather than directly measuring the pH or eosinophil counts, Dr. Patel and associates prospectively validated the diagnostic test performance of an add-on endoscopic mucosal impedance device that might enable the gastroenterologist to rule out GERD or rule in eosinophilic esophagitis during the index endoscopy with reasonable accuracy (AUC above 0.8 to rule out GERD or rule in eosinophilic esophagitis) while adding 2-3 minutes of procedure time. One patient was admitted for chest pain after use of the device but was discharged without complication, and the authors caution against use in severe fibrostenotic disease.
While work to refine a clinical prediction model with this technology is ongoing, the promise of diagnosing and following common esophageal conditions of GERD and eosinophilic esophagitis during endoscopy would have clear value in expediting care and enhancing compliance with treatment.
Eric D. Shah, MD, MBA, is assistant professor of medicine, director of gastrointestinal motility, esophageal, and swallowing disorders center, Geisel School of Medicine, Dartmouth College, Hanover, N.H. He has no disclosures.
.
Source: American Gastroenterological Association
Each group showed a significantly different (P less than .01) pattern of mucosal impedance (MI), or disruption of mucosal integrity, along the esophageal axis, wrote Dhyanesh A. Patel, MD, of Vanderbilt University Medical Center in Nashville, Tenn., and his associates. Patients without GERD had higher MI values along all esophageal segments, while GERD was characterized by below-normal values in the distal esophagus only, and eosinophilic esophagitis led to low values throughout the esophagus.
The findings were validated in a separate patient cohort, and the only reported adverse event was an episode of mild chest pain. “This contour heatmap could easily be employed to establish a diagnosis during endoscopy, independent of biopsy or pH monitoring,” the investigators wrote in Gastroenterology. They cautioned that the balloon catheter cannot be safely used in patients with severe fibrostenotic disease.
Current definitive diagnostics for GERD leave much to be desired. Transnasal probes are imprecise and uncomfortable, and they can be insensitive if discomfort causes patients to vary normal activity or skip meals. Wireless ambulatory pH monitoring is more tolerable but unreliable and measures only acidity of refluxed material at a single point along the esophagus. These tests also “fail to account for day-to-day variability of reflux, as they only provide a 24- to 48-hour snapshot of a disease process that is chronic in nature,” the researchers wrote. Eosinophilic esophagitis is becoming more common and usually requires proximal and distal biopsies for diagnosis.
Mucosal impedance contour pattern testing is based on the fact that both GERD and eosinophilic esophagitis involve increased distance between esophageal epithelial cells. The amount of intercellular dilatation correlates inversely with MI values. In proof-of-concept studies, individuals with GERD, non-GERD, eosinophilic esophagitis, and achalasia had distinct MI patterns. However, these studies tested a single-channel catheter system that took only point measurements and was subject to interoperator variability. To improve on this concept, Dr. Patel and his associates mounted radial and axial sensors on a balloon catheter to measure MI at 180-degree intervals along a 10-cm esophageal segment.
They tested the new device prospectively in 69 patients undergoing esophagogastroduodenoscopy with or without pH monitoring (which was used as the standard). In all, 24 patients had GERD, 21 had eosinophilic esophagitis, and 24 had normal findings. By using the intercept and slope of the balloon MI measurements, the researchers detected GERD with an area under the receiver operating characteristic curve (AUC) of 0.67, eosinophilic esophagitis with an AUC of 0.84, and non-GERD with an AUC of 0.83.
These findings held up in a separate validation cohort of 36 patients (28 with GERD and eight with eosinophilic esophagitis) from three tertiary care centers. The probability of eosinophilic esophagitis was highest in patients with low distal MI values (that is, a low intercept) and a low slope (showing that MI values remained low proximally). A low distal MI intercept with a steeper positive slope suggested GERD, while a higher distal MI intercept with a steep slope signified non-GERD.
The system “potentially obviates the need for 24- to 48-hour ambulatory wireless pH monitoring or esophageal biopsies for histopathology,” the researchers concluded. “This can help reduce diagnostic and treatment latency and might allow for monitoring disease activity over time.”
The National Institutes of Health funded the external validation analysis. Diversatek Healthcare, which patented the device together with Vanderbilt University, gave research funding to four coinvestigators, including the senior author. Dr. Patel and the other five coinvestigators reported having no conflicts of interest.
SOURCE: Patel DA et al. Gastroenterology. 2019 Jan 31. doi: 10.1053/j.gastro.2019.01.253.
.
Source: American Gastroenterological Association
Each group showed a significantly different (P less than .01) pattern of mucosal impedance (MI), or disruption of mucosal integrity, along the esophageal axis, wrote Dhyanesh A. Patel, MD, of Vanderbilt University Medical Center in Nashville, Tenn., and his associates. Patients without GERD had higher MI values along all esophageal segments, while GERD was characterized by below-normal values in the distal esophagus only, and eosinophilic esophagitis led to low values throughout the esophagus.
The findings were validated in a separate patient cohort, and the only reported adverse event was an episode of mild chest pain. “This contour heatmap could easily be employed to establish a diagnosis during endoscopy, independent of biopsy or pH monitoring,” the investigators wrote in Gastroenterology. They cautioned that the balloon catheter cannot be safely used in patients with severe fibrostenotic disease.
Current definitive diagnostics for GERD leave much to be desired. Transnasal probes are imprecise and uncomfortable, and they can be insensitive if discomfort causes patients to vary normal activity or skip meals. Wireless ambulatory pH monitoring is more tolerable but unreliable and measures only acidity of refluxed material at a single point along the esophagus. These tests also “fail to account for day-to-day variability of reflux, as they only provide a 24- to 48-hour snapshot of a disease process that is chronic in nature,” the researchers wrote. Eosinophilic esophagitis is becoming more common and usually requires proximal and distal biopsies for diagnosis.
Mucosal impedance contour pattern testing is based on the fact that both GERD and eosinophilic esophagitis involve increased distance between esophageal epithelial cells. The amount of intercellular dilatation correlates inversely with MI values. In proof-of-concept studies, individuals with GERD, non-GERD, eosinophilic esophagitis, and achalasia had distinct MI patterns. However, these studies tested a single-channel catheter system that took only point measurements and was subject to interoperator variability. To improve on this concept, Dr. Patel and his associates mounted radial and axial sensors on a balloon catheter to measure MI at 180-degree intervals along a 10-cm esophageal segment.
They tested the new device prospectively in 69 patients undergoing esophagogastroduodenoscopy with or without pH monitoring (which was used as the standard). In all, 24 patients had GERD, 21 had eosinophilic esophagitis, and 24 had normal findings. By using the intercept and slope of the balloon MI measurements, the researchers detected GERD with an area under the receiver operating characteristic curve (AUC) of 0.67, eosinophilic esophagitis with an AUC of 0.84, and non-GERD with an AUC of 0.83.
These findings held up in a separate validation cohort of 36 patients (28 with GERD and eight with eosinophilic esophagitis) from three tertiary care centers. The probability of eosinophilic esophagitis was highest in patients with low distal MI values (that is, a low intercept) and a low slope (showing that MI values remained low proximally). A low distal MI intercept with a steeper positive slope suggested GERD, while a higher distal MI intercept with a steep slope signified non-GERD.
The system “potentially obviates the need for 24- to 48-hour ambulatory wireless pH monitoring or esophageal biopsies for histopathology,” the researchers concluded. “This can help reduce diagnostic and treatment latency and might allow for monitoring disease activity over time.”
The National Institutes of Health funded the external validation analysis. Diversatek Healthcare, which patented the device together with Vanderbilt University, gave research funding to four coinvestigators, including the senior author. Dr. Patel and the other five coinvestigators reported having no conflicts of interest.
SOURCE: Patel DA et al. Gastroenterology. 2019 Jan 31. doi: 10.1053/j.gastro.2019.01.253.
FROM GASTROENTEROLOGY
More fiber looks safe, might benefit ICU patients
MIAMI –
“Higher fiber intake was associated with greater preservation of short-chain fatty acid–producing bacteria, even after we adjusted for antibiotics and acute severity of illness,” said Yichun Fu, a fourth-year medical student at Columbia University, New York, at the annual Gut Microbiota for Health World Summit.
She explained that, after 72 hours on the high-fiber diet, only 11% of patients had abdominal distension noted in their EMRs, compared with 36% of patients who received no dietary fiber (P less than .01). Fiber was not associated with bowel obstruction, high gastric residuals, enteric infections, edema, or diarrhea. She and her associates presented the findings in a poster at the meeting sponsored by the American Gastroenterological Association and the European Society for Neurogastroenterology and Motility.
Dietary fiber is a prebiotic that increases the abundance of short-chain fatty acid (SCFA)–producing bacteria in the gut. Growing evidence links these bacteria and their metabolites – such as acetate, propionate, and butyrate – to immunomodulatory benefits and suggests that they help maintain gut barrier function, glucose homeostasis, adipose tissue lipolysis, and normal blood pressure. Thus, fiber for ICU patients might make sense, but relevant dietary guidelines rarely address the topic. In practice, fiber is often withheld in the ICU because of concerns that it might cause bloating or diarrhea, Ms. Fu said.
For the study, the researchers performed 16s ribosomal RNA sequencing on baseline and 72-hour rectal swabs collected from 129 consecutive adults newly admitted to the ICU. Patients were eligible for the study regardless of whether they received nothing by mouth, enteral feeding, or food by mouth. They were grouped in tertiles based on fiber intake over 72 hours, corrected by caloric intake. The resulting groups were dubbed “no fiber” (median and interquartile range, 0 grams), “low fiber” (median, 11.2 g; IQR, 3.8-18.2 g), and “high fiber” (median, 39.3 g; IQR, 4.7-50.2 g).
Patients in these three groups had a similar relative abundance of SCFA-producing bacteria at baseline. At 72 hours, the high-fiber group had a significantly greater relative abundance of SCFA producers than the no fiber group (P = .01). Compared with no fiber, high-fiber intake also correlated with significantly increased gut bacterial diversity (P = .04) and a lower relative abundance of Enterococcus bacteria (P less than .01). None of these measures differed significantly between the no-fiber and low-fiber groups.
The groups were demographically and clinically similar at baseline, except that the high-fiber group had lower Acute Physiology and Chronic Health Evaluation IV scores (P = .02) and was less likely to receive antibiotics, mechanical ventilation, hemodialysis, or vasopressors (P less than .01). After correcting for these differences, each 10-g increase in fiber intake over 72 hours correlated with a 0.3% median increase in the relative abundance of SCFA-producing bacteria (estimated IQR, 0.10%-0.46%; P less than .01).
“Fiber may be a simple candidate therapy for ICU patients,” the researchers concluded. The team is now designing a prospective, interventional study to further test whether fiber can modify the gut microbiome to benefit ICU patients, Ms. Fu explained.
Funders included the American Gastroenterological Association, the National Institutes of Health, and the Feldstein Medical Foundation. Ms. Fu reported no competing interests.
MIAMI –
“Higher fiber intake was associated with greater preservation of short-chain fatty acid–producing bacteria, even after we adjusted for antibiotics and acute severity of illness,” said Yichun Fu, a fourth-year medical student at Columbia University, New York, at the annual Gut Microbiota for Health World Summit.
She explained that, after 72 hours on the high-fiber diet, only 11% of patients had abdominal distension noted in their EMRs, compared with 36% of patients who received no dietary fiber (P less than .01). Fiber was not associated with bowel obstruction, high gastric residuals, enteric infections, edema, or diarrhea. She and her associates presented the findings in a poster at the meeting sponsored by the American Gastroenterological Association and the European Society for Neurogastroenterology and Motility.
Dietary fiber is a prebiotic that increases the abundance of short-chain fatty acid (SCFA)–producing bacteria in the gut. Growing evidence links these bacteria and their metabolites – such as acetate, propionate, and butyrate – to immunomodulatory benefits and suggests that they help maintain gut barrier function, glucose homeostasis, adipose tissue lipolysis, and normal blood pressure. Thus, fiber for ICU patients might make sense, but relevant dietary guidelines rarely address the topic. In practice, fiber is often withheld in the ICU because of concerns that it might cause bloating or diarrhea, Ms. Fu said.
For the study, the researchers performed 16s ribosomal RNA sequencing on baseline and 72-hour rectal swabs collected from 129 consecutive adults newly admitted to the ICU. Patients were eligible for the study regardless of whether they received nothing by mouth, enteral feeding, or food by mouth. They were grouped in tertiles based on fiber intake over 72 hours, corrected by caloric intake. The resulting groups were dubbed “no fiber” (median and interquartile range, 0 grams), “low fiber” (median, 11.2 g; IQR, 3.8-18.2 g), and “high fiber” (median, 39.3 g; IQR, 4.7-50.2 g).
Patients in these three groups had a similar relative abundance of SCFA-producing bacteria at baseline. At 72 hours, the high-fiber group had a significantly greater relative abundance of SCFA producers than the no fiber group (P = .01). Compared with no fiber, high-fiber intake also correlated with significantly increased gut bacterial diversity (P = .04) and a lower relative abundance of Enterococcus bacteria (P less than .01). None of these measures differed significantly between the no-fiber and low-fiber groups.
The groups were demographically and clinically similar at baseline, except that the high-fiber group had lower Acute Physiology and Chronic Health Evaluation IV scores (P = .02) and was less likely to receive antibiotics, mechanical ventilation, hemodialysis, or vasopressors (P less than .01). After correcting for these differences, each 10-g increase in fiber intake over 72 hours correlated with a 0.3% median increase in the relative abundance of SCFA-producing bacteria (estimated IQR, 0.10%-0.46%; P less than .01).
“Fiber may be a simple candidate therapy for ICU patients,” the researchers concluded. The team is now designing a prospective, interventional study to further test whether fiber can modify the gut microbiome to benefit ICU patients, Ms. Fu explained.
Funders included the American Gastroenterological Association, the National Institutes of Health, and the Feldstein Medical Foundation. Ms. Fu reported no competing interests.
MIAMI –
“Higher fiber intake was associated with greater preservation of short-chain fatty acid–producing bacteria, even after we adjusted for antibiotics and acute severity of illness,” said Yichun Fu, a fourth-year medical student at Columbia University, New York, at the annual Gut Microbiota for Health World Summit.
She explained that, after 72 hours on the high-fiber diet, only 11% of patients had abdominal distension noted in their EMRs, compared with 36% of patients who received no dietary fiber (P less than .01). Fiber was not associated with bowel obstruction, high gastric residuals, enteric infections, edema, or diarrhea. She and her associates presented the findings in a poster at the meeting sponsored by the American Gastroenterological Association and the European Society for Neurogastroenterology and Motility.
Dietary fiber is a prebiotic that increases the abundance of short-chain fatty acid (SCFA)–producing bacteria in the gut. Growing evidence links these bacteria and their metabolites – such as acetate, propionate, and butyrate – to immunomodulatory benefits and suggests that they help maintain gut barrier function, glucose homeostasis, adipose tissue lipolysis, and normal blood pressure. Thus, fiber for ICU patients might make sense, but relevant dietary guidelines rarely address the topic. In practice, fiber is often withheld in the ICU because of concerns that it might cause bloating or diarrhea, Ms. Fu said.
For the study, the researchers performed 16s ribosomal RNA sequencing on baseline and 72-hour rectal swabs collected from 129 consecutive adults newly admitted to the ICU. Patients were eligible for the study regardless of whether they received nothing by mouth, enteral feeding, or food by mouth. They were grouped in tertiles based on fiber intake over 72 hours, corrected by caloric intake. The resulting groups were dubbed “no fiber” (median and interquartile range, 0 grams), “low fiber” (median, 11.2 g; IQR, 3.8-18.2 g), and “high fiber” (median, 39.3 g; IQR, 4.7-50.2 g).
Patients in these three groups had a similar relative abundance of SCFA-producing bacteria at baseline. At 72 hours, the high-fiber group had a significantly greater relative abundance of SCFA producers than the no fiber group (P = .01). Compared with no fiber, high-fiber intake also correlated with significantly increased gut bacterial diversity (P = .04) and a lower relative abundance of Enterococcus bacteria (P less than .01). None of these measures differed significantly between the no-fiber and low-fiber groups.
The groups were demographically and clinically similar at baseline, except that the high-fiber group had lower Acute Physiology and Chronic Health Evaluation IV scores (P = .02) and was less likely to receive antibiotics, mechanical ventilation, hemodialysis, or vasopressors (P less than .01). After correcting for these differences, each 10-g increase in fiber intake over 72 hours correlated with a 0.3% median increase in the relative abundance of SCFA-producing bacteria (estimated IQR, 0.10%-0.46%; P less than .01).
“Fiber may be a simple candidate therapy for ICU patients,” the researchers concluded. The team is now designing a prospective, interventional study to further test whether fiber can modify the gut microbiome to benefit ICU patients, Ms. Fu explained.
Funders included the American Gastroenterological Association, the National Institutes of Health, and the Feldstein Medical Foundation. Ms. Fu reported no competing interests.
REPORTING FROM GMFM 2019