Collagenous colitis and eosinophilic gastritis in a 4-year old girl: a case report and review of the literature

Clinicopathologic Characterization of Lymphocytic Colitis in the Pediatric Population

BACKGROUND

Lymphocytic colitis (LC) in the pediatric population has been associated with immune dysregulation.

METHODS

Single-center retrospective study of pediatric LC.

RESULTS

50 patients (35 female, 70%) with a median age of 12 years at diagnosis (interquartile range: 5.7-15.8) of LC were identified. At presentation, 11 patients (22%) had malnutrition, 16 (32%) had a known underlying immune dysregulation, 4 (8%) had celiac disease (CD), and none had a diagnosis of inflammatory bowel disease. The most common medications prior to diagnosis were non-steroidal anti-inflammatory drugs, proton pump inhibitor, and selective serotonin reuptake inhibitors (10% each). Colonic biopsies showed a median number of intraepithelial lymphocytes (IELs)/100 epithelial cells of 48 (range: 25-85), and only 10% of cases had neutrophilic cryptitis. Upper gastrointestinal tract findings included lymphocytic esophagitis (4%), and duodenal IELs without and with villous blunting (9% each) (n: 47). Ten patients (23%) had increased IELs in the terminal ileum (n: 43). Treatments including 5-ASA, budesonide, prednisone, and gluten-free diet improved symptoms in <50% of patients (n: 42), and all follow-up colonoscopies showed persistent LC (n: 13).

CONCLUSION

Our study supports the association of LC with immune-mediated conditions, most commonly celiac disease. Symptomatic improvement was seen in <50% of patients with none of the patients with repeat colonoscopy showing histologic improvement.

Joint ESPGHAN/NASPGHAN Guidelines on Childhood Eosinophilic Gastrointestinal Disorders Beyond Eosinophilic Esophagitis

INTRODUCTION

Eosinophilic gastrointestinal disorders beyond eosinophilic esophagitis (non-EoE EGIDs) are rare chronic inflammatory disorders of the gastrointestinal (GI) tract. Diagnosis is based on clinical symptoms and histologic findings of eosinophilic inflammation after exclusion of a secondary cause or systemic disease. Currently, no guidelines exist for the evaluation of non-EoE EGIDs. Therefore, the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) and the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) formed a task force group to provide consensus guidelines for childhood non-EoE EGIDs.

METHODS

The working group was composed of pediatric gastroenterologists, adult gastroenterologists, allergists/immunologists, and pathologists. An extensive electronic literature search of the MEDLINE, EMBASE, and Cochrane databases was conducted up to February 2022. General methodology was used in the formulation of recommendations according to the Appraisal of Guidelines for Research and Evaluation (AGREE) II and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to meet current standards of evidence assessment.

RESULTS

The guidelines provide information on the current concept of non-EoE EGIDs, disease pathogenesis, epidemiology, clinical manifestations, diagnostic and disease surveillance procedures, and current treatment options. Thirty-four statements based on available evidence and 41 recommendations based on expert opinion and best clinical practices were developed.

CONCLUSION

Non-EoE EGIDs literature is limited in scope and depth, making clear recommendations difficult. These consensus-based clinical practice guidelines are intended to assist clinicians caring for children affected by non-EoE EGIDs and to facilitate high-quality randomized controlled trials of various treatment modalities using standardized, uniform disease definitions.

Microscopic colitis in older adults: impact, diagnosis, and management

Microscopic colitis (comprising lymphocytic and collagenous colitis, albeit an incomplete variant is gaining recognition as well) is a chronic, immune-mediated inflammatory state of the lower gastrointestinal tract (colon). The diagnosis requires diagnostic colonoscopy with characteristic histopathological findings. They have a propensity to present in senior populations (above 60 years of age), particularly women – who are approximately 2.5–3 times more likely to develop microscopic colitis. Preexisting other immune-inflammatory diseases are also shown to predispose patients for the development of microscopic colitis. The classic presentation is profuse watery diarrhea, often during the night or early morning hours. Fecal incontinence and abdominal pain are frequent as well. Thus, the disease impacts patients’ quality of life and well-being. The first described cases date back to the seventies and eighties of the twentieth century, thereby they can be considered fairly recently discovered disease states. Our understanding of the disease and its pathophysiology is still incomplete. Although there is a lack of unified recommendation for treatment, most clinicians prefer the use of budesonide, and most published guidelines regard this locally acting glucocorticoid as the therapy of choice. In our article, we aimed for a brief, noncomprehensive overview of the clinical significance, diagnosis, and management of microscopic colitis.

Diagnosis and Management of Microscopic Colitis in Pediatric Patients

Microscopic colitis (MC) is an inflammatory disease of the colon, characterized by chronic watery diarrhea with distinguishing histologic findings despite normal endoscopic appearance of the colonic mucosa. MC is a common cause of diarrhea in older adults, though it has been infrequently reported in children and adolescents. As MC is rare in the pediatric population, and the clinical presentation is non-specific, increased awareness of this disease amongst pediatric clinicians and pathologists is essential for timely diagnosis, which requires performing colonoscopy with biopsy. The etiology of MC is incompletely understood, but current theories in pathogenesis inform management strategies. The goals of management in pediatric MC should be to achieve symptomatic improvement while minimizing adverse effects of treatment. Many patients who achieve clinical response have symptomatic recurrence after discontinuation of initial therapy, and may require maintenance medication therapy to sustain remission. This review aims to summarize the epidemiology and risk factors, clinical features, diagnosis, theories regarding pathogenesis, and suggested management approaches for MC in the pediatric population.

Microscopic colitis: controversies in clinical symptoms and autoimmune comorbidities

BACKGROUND

Microscopic colitides are chronic immune-inflammatory bowel diseases. The typical presentation is chronic, watery diarrhoea. Inflammation mostly cannot be visualized via macroscopic inspection. The diagnosis thus requires histologic sampling. The clinical picture can vary. New investigations can prove valuable in setting up recommendations.

PATIENTS

A total of 103 patients with microscopic colitis (MC) [28 lymphocytic colitis (LC) 27.2%, 75 collagenous colitis (CC) 72.8%] in the Clinical Centre of the University of Debrecen (tertiary care centre) were included, diagnosed between 1993 and 2020. We aimed for a retrospective analysis characterizing Hungarian MC patients. We sought to compare two subgroups of patients (with either LC or CC). Our investigation focussed on dominant alteration of stool habits, autoimmune and allergic comorbidities. Autoimmune diseases were diagnosed in 39% (40) of the patients, allergic diseases in 26.2% (27) of patients and 22.2% of tested patients had alimentary hypersensitivity to certain foods (18 cases out of 81 tested).

RESULTS

Age of diagnosis was younger in LC (44.5 years, SD: 5.3 vs. 51.9 years, SD: 12.8, difference= 7.4 years p = .0151). Autoimmune diseases were equally frequent in the two groups (LC: 10 patients 36%, CC: 30 patients, 40%, difference: 4%, p = .7124). Food-linked hypersensitivities were more common in CC (LC: 1 patient, CC: 17 patients). Difference in allergic diseases (asthma, rhinitis, urticaria) did not differ between groups (LC: 6 patients, 21%; CC: 21 patients, 28%, difference: 7% p = .4739). One-third of the patients did not complain about chronic diarrhoea. These patients had chronic constipation as the main symptom (34 patients, 33%).

CONCLUSION

Pre-existing autoimmune and allergic diseases were common in patients with MC. Chronic watery diarrhoea is not experienced in many cases. The absence of certain symptoms should not be used to rule out the condition.

Lymphocytic and collagenous colitis in children and adolescents: Comprehensive clinicopathologic analysis with long-term follow-up

Microscopic colitis (MC) is characterized by chronic watery diarrhea, endoscopically normal findings, and abnormal histology. While mostly encountered in adults, pediatric cases are rare and may show varying presentations. Our pathology data system was searched from 1984 to 2019 for patients ≤18 years of age with a lymphocytic colitis (LC) or collagenous colitis (CC) pattern of injury. Twenty-seven cases (23 LC and 4 CC) were retrieved. LC was more prevalent than CC (85% vs 15%, respectively) and affected slightly younger individuals (mean, 9.8 years versus 12.25 years). Immune dysregulation was documented in 11 (41%) patients. Most patients presented with watery diarrhea (n = 26, 96%) and either abdominal pain (n = 18, 67%), nausea/vomiting (n = 5, 19%), flatulence (n = 6, 22%), and/or weight loss (n = 1, 4%). A subset of patients (n = 10, 37%) demonstrated endoscopic abnormalities. Histologically, some patients with LC and CC displayed focal cryptitis or crypt abscess formation (n = 7, 26%) and focally increased crypt apoptosis (n = 9, 33%) in the absence of chronic injury. Clinical follow-up data were available for 23 (85%) patients with variable clinical responses recorded. Only 8 patients experienced complete symptom resolution. Twelve patients (11 LC and 1 CC) had subsequent biopsy material; of which, one developed histologic features of inflammatory bowel disease and another was found to have a CTLA-4 deficiency. Our study shows that pediatric patients with MC may have atypical clinical, histologic, and endoscopic findings and variable clinical responses. Underlying inflammatory and/or genetic conditions may be eventually unmasked, and genetic testing may be helpful in a small subset of patients.

Optimal management of collagenous colitis: a review

Collagenous colitis (CC) is an increasingly recognized cause of chronic inflammatory bowel disease characterized by watery non-bloody diarrhea. As a lesser studied inflammatory bowel disease, many aspects of the CC's natural history are poorly understood. This review discusses strategies to optimally manage CC. The goal of therapy is to induce clinical remission, <3 stools a day or <1 watery stool a day with subsequent improved quality of life (QOL). Antidiarrheal can be used as monotherapy or with other medications to control diarrhea. Budesonide therapy has revolutionized treatment and is superior to prednisone, however, the treatment is associated with high-relapse rates and the management of refractory disease is challenging. Ongoing trials will address the safety and efficacy of low-dose maintenance therapy. For those with refractory disease, case reports and case series support the role of biologic agents. Diversion of the fecal stream normalizes colonic mucosal changes and ileostomy may be considered where anti-tumor necrosis factor (TNF)-α agents are contraindicated. Underlying celiac disease, bile salt diarrhea, and associated thyroid dysfunction should be ruled out. The author recommends smoking cessation as well as avoidance of nonsteroidal anti-inflammatories as well as other associated medications.

Diagnosis and management of microscopic colitis: current perspectives

Collagenous colitis and lymphocytic colitis, together constituting microscopic colitis, are common causes of chronic diarrhea. They are characterized clinically by chronic nonbloody diarrhea and a macroscopically normal colonic mucosa where characteristic histopathological findings are seen. Previously considered rare, they now have emerged as common disorders that need to be considered in the investigation of the patient with chronic diarrhea. The annual incidence of each disorder is five to ten per 100,000 inhabitants, with a peak incidence in 60- to 70-year-old individuals and a predominance of female patients in collagenous colitis. The etiology and pathophysiology are not well understood, and the current view suggests an uncontrolled mucosal immune reaction to various luminal agents in predisposed individuals. Clinical symptoms comprise chronic diarrhea, abdominal pain, fatigue, weight loss, and fecal incontinence that may impair the patient's health-related quality of life. An association is reported with other autoimmune disorders, such as celiac disease, thyroid disorders, diabetes mellitus, and arthritis. The best-documented treatment, both short-term and long-term, is budesonide, which induces clinical remission in up to 80% of patients after 8 weeks' treatment. However, after successful budesonide therapy is ended, recurrence of clinical symptoms is common, and the best possible long-term management deserves further study. The long-term prognosis is good, and the risk of complications, including colonic cancer, is low. We present an update of the epidemiology, pathogenesis, diagnosis, and management of microscopic colitis.

Collagenous colitis associated with protein losing enteropathy in a toddler

Collagenous mucosal inflammatory disease is a rare gastrointestinal disorder that involves the columnar lining of gastric and intestinal mucosa and is characterized by a distinct subepithelial collagen deposition. Recent clinical and pathological evidence have indicated that collagenous mucosal inflammatory disease can be extensive disease that may concomitantly involve several gastrointestinal sites at the same time. This entity, however, occurs infrequently in children. It is even less common to find concomitant depositions of collagen in the mucosa of gastrointestinal sites other than the colon. Only two cases in pediatric literature reported concomitant involvement, one with gastric and colonic involvement and the other one with gastroduodenocolitis. We are reporting a 15-month-old boy who presented with severe diarrhea and diffuse edema secondary to hypoalbuminemia. Further testing documented protein losing enteropathy (PLE) associated with collagenous colitis.

Clinical features and treatment responses in pediatric lymphocytic and collagenous colitis

OBJECTIVE

Microscopic colitis (MC) is prevalent in adults investigated for chronic watery diarrhea, yet characterization of pediatric MC is limited.

METHODS

Our pathology database was searched from 1995 to 2011 for pediatric cases of lymphocytic colitis (LC) or collagenous colitis (CC). Those with diarrhea persisting for >2 weeks and visually normal colonoscopy were accepted as cases. Demographics, laboratory results, medication use within 3 months of presentation, medical and family history of autoimmune disease, and response to treatment were abstracted.

RESULTS

A total of 27 cases were histologically consistent with MC on biopsy; 5 with concomitant enteric infection or isolated abdominal pain were excluded. Twenty-two cases of MC (female patients, 59%; median age at diagnosis, 15.3 years) were included (19 LC and 3 CC). Two had type 1 diabetes mellitus, 2 were anti-nuclear antibody positive, and 2 had common variable immunodeficiency. Of 20 patients who underwent an esophagogastroduodenoscopy, 1 had collagenous sprue and 4 had celiac disease. One presented after the clearance of recurrent Clostridium difficile infection. Previous drug exposures included nonsteroidal anti-inflammatory drugs (n = 7), proton pump inhibitors (n = 6), and selective serotonin reuptake inhibitors (n = 3). Common symptoms in addition to diarrhea included abdominal pain (77.3%) and weight loss (27.3%). Of 17 patients with follow-up, all of the 8 treated with steroids had some response: 57.1% (4/7) responded to mesalamine and 42.9% (3/7) responded to bismuth subsalicylate.

CONCLUSIONS

In this cohort of pediatric patients, LC was much more common than CC. As described in adults, we observed associations with celiac disease, type 1 diabetes mellitus, and medications; we additionally saw an association with immunodeficiency. Our patients showed greater response to steroids than mesalamine or bismuth.

Collagenous colitis in children and adolescents: study of 7 cases and literature review

The aim of this study is to examine the clinical and pathologic characteristics of collagenous colitis (CC) in children and adolescents. Seven patients (five females and two males, median age: 13 years, ranging from 4 to 16) were included. Four (of 7, 57%) patients presented with non-bloody watery diarrhea, one with alternating constipation and diarrhea with rectal prolapse, one with constipation, and one with normal bowel movement. Abdominal pain and weight loss were manifested in 80 and 40% patients, respectively. Two patients had celiac disease in remission. None of the patients took non-steroidal antiinflammatory agents. All patients had normal colonoscopy, but had typical histologic features of CC in colon biopsies. Four patients had clinical follow-up (24-75 months duration, median 54 months): three patients had no gastrointestinal symptoms upon follow-up, but one patient had continued symptoms of alternating diarrhea and constipation. Two patients had follow-up biopsies: one showed persistence of CC, and one had complete histologic resolution. We conclude that while CC is rare in children and adolescents, the clinical presentation is similar to adults, with a female preponderance, presentation with diarrhea and abdominal pain, and an association with celiac disease and other autoimmune disorders. However, compared with adults, children and adolescents are more likely to have weight loss and an atypical presentation including alternating constipation and diarrhea, constipation alone or normal bowel movements. Treatment is less standardized in children and adolescents with CC.

Collagenous colitis-like condition in immunosuppressed infant baboons

BACKGROUND

Collagenous colitis is a chronic inflammatory bowel disease of unknown etiology. It is fairly common in adult humans, but rare in infants, and has been associated with autoimmune disorders.

METHODS

We report four infant baboons (age 7-12 months) that had received a transplant at 3 months of age and subsequent immunosuppressive therapy for periods of 4-10 months. All presented identical symptoms within a period of 4 weeks, including weight loss associated with chronic watery diarrhea that was unresponsive to standard antimicrobial treatment.

RESULTS

Clinical chemistry evaluations were within normal ranges, viral causes were ruled out, and fecal and blood cultures were repeatedly negative. At necropsy, two infant baboons were found to have a form of collagenous colitis. In the remaining two baboons that had identical clinical features, immunosuppressive therapy was discontinued and treatment with budesonide was initiated. Both baboons recovered and remained well on no medication until the end of follow-up (24 months).

CONCLUSIONS

Collagenous colitis has occasionally been reported in patients with organ transplants. It has been reported only once previously in baboons. The four cases reported here strongly suggest that 1) clinical features as well as histopathological findings of collagenous colitis in baboons are very similar to those in human patients; 2) it was associated with the immunocompromised state of the baboons, as two nonimmunosuppressed age-matched baboons in close proximity did not develop the condition; and 3) it may have had an infectious origin, as all four cases developed within a 4-week period of time.

Familial collagenous colitis involving a 6-year old child

Collagenous colitis is a recognised cause of persistent, non-bloody, watery diarrhoea. There are few cases of collagenous colitis reported in children or occurring within families. To our knowledge, no familial cases under 14 years of age have been reported previously; we describe a case of familial collagenous colitis affecting a 6-year old girl and her mother. The relevant published literature is reviewed and management is discussed. Colonic mucosal biopsies should be considered in both adults and children presenting with persistent watery diarrhoea even in the absence of any macroscopic abnormality at colonoscopy.

Microscopic colitis in children

BACKGROUND

Microscopic colitis typically presents with chronic watery nonbloody diarrhea with normal endoscopy findings but abnormal inflammatory histopathological findings. As it is mainly a condition of the elderly, pediatric data is scarce.

AIMS

To describe and characterize children with microscopic colitis.

METHODS

The pathology database at the University of Alberta Hospital together with the pediatric inflammatory bowel disease database at the Stollery Children's Hospital were both searched from September 1996 to May 2008. Charts of all children under the age of 17 years who fulfilled the diagnostic criteria of microscopic colitis were examined.

RESULTS

Eleven children (four girls, mean age at diagnosis 11.2 years, +/- 4.4 years) fulfilled the inclusion criteria. The patients were followed up for a mean of 24.8 months (standard deviation, SD 15.2 months). Two patients were on proton pump inhibitors, two had stool organisms, and two had immunodeficiency. All patients had normal endoscopy and colonoscopy on visualization. Five patients were diagnosed with lymphocytic colitis and the rest had nonspecific/eosinophilic microscopic colitis. The majority of children responded to mesalazine. One patient with immunodeficiency was difficult to manage.

CONCLUSIONS

Microscopic colitis is rare in children. Microscopic eosinophilic colitis is an underdescribed variant of microscopic colitis. The majority of children with microscopic colitis respond well to aminosalicylic acid (5-ASA) medications. Microscopic colitis associated with immunodeficiency can be very challenging to manage. Large multicenter pediatric trials with long-term follow-up are needed to allow investigators to have a better understanding of this rare condition in children.

Diagnosis and management of microscopic colitis

Microscopic colitis, comprising collagenous and lymphocytic colitis, is characterized clinically by chronic watery diarrhea, and a macroscopically normal colonic mucosa where diagnostic histopathological features are seen on microscopic examination. The annual incidence of each disorder is 4-6/100,000 inhabitants, with a peak incidence in 60-70-year-old individuals and a noticeable female predominance for collagenous colitis. The etiology is unknown. Chronic diarrhea, abdominal pain, weight loss, fatigue and fecal incontinence are common symptoms, which impair the health-related quality of life of the patient. There is an association with other autoimmune disorders such as celiac disease, diabetes mellitus, thyroid disorders and arthritis. Budesonide is the best-documented short-term treatment, but the optimal long-term strategy needs further study. The long-term prognosis is good and the risk of complications including colonic cancer is low.

Microscopic colitis: a common and an easily overlooked cause of chronic diarrhoea

Microscopic colitis, comprising collagenous colitis and lymphocytic colitis, is characterised clinically by chronic watery diarrhoea, a macroscopically normal colonic mucosa where diagnostic histopathological features are seen on microscopic examination. The annual incidence of each disorder is 4-6/100,000 inhabitants, with a peak incidence in 60-70 year old individuals and a noticeable female predominance in collagenous colitis. The aetiology is unknown. Abdominal pain, weight loss, fatigue, and faecal incontinence are common symptoms in addition to chronic diarrhoea that impair the health-related quality of life of the patient. There is an association to other autoimmune disorders such as celiac disease, diabetes mellitus, thyroid disorders and arthritis. Budesonide is the best-documented short-term treatment, but the optimal long-term strategy needs further study. The long-term prognosis is good and the risk of complications including colonic cancer is low.

Interventions for treating collagenous colitis

BACKGROUND

Collagenous colitis is a cause of chronic diarrhea. Treatment has been based mainly on anecdotal evidence. This review was performed to identify therapies for collagenous colitis that have been proven in randomized trials.

OBJECTIVES

To determine effective treatments for patients with collagenous colitis.

SEARCH STRATEGY

Relevant papers published between 1970 and December 2007 were identified via the MEDLINE and PUBMED databases. Manual searches from the references of identified papers, as well as review papers on collagenous or microscopic colitis were performed to identify additional studies. Abstracts from major gastroenterological meetings were searched to identify research submitted in abstract form only. Finally, the Cochrane Controlled Trials Register and the Cochrane Inflammatory Bowel Disease and Functional Bowel Disorders Group Specialized Trials Register were searched for other studies.

SELECTION CRITERIA

Ten randomized trials were identified. Seven of these compared active treatment to placebo for treating active disease. Of these, 1 trial studied bismuth subsalicylate, 1 trial studied Boswellia serrata extract, 3 trials studies budesonide, 1 trial studied prednisolone, and 1 trial studied probiotics. One trial compared mesalamine to mesalamine + cholestyramine for treating active disease. Two trials compared budesonide to placebo in maintaining response induced by budesonide.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by each author onto 2x2 tables (treatment versus comparator and response versus no response). For therapies assessed in one trial only, P-values were derived using the chi-square test. For therapies assessed in more than one trial, summary test statistics were derived using the Peto odds ratio and 95% confidence intervals. Data were combined for analysis only if the outcomes were sufficiently similar in definition.

MAIN RESULTS

In treating active disease, there were 9 patients with collagenous colitis in the trial studying bismuth subsalicylate (nine 262 mg tablets daily for 8 weeks). Clinical response occurred in 100% of patients who received bismuth subsalicylate compared to 0% of patients who received placebo (P = 0.03). Thirty-one patients were enrolled in the trial studying Boswellia serrata extract (three 400 mg capsules daily for 8 weeks). Clinical response occurred in 44% of patients who received Boswellia serrata extract compared to 27% of patients who received placebo (P = 0.32). A total of 94 patients were enrolled in 3 trials studying budesonide (9 mg daily or in a tapering schedule for 6 to 8 weeks). Clinical response occurred in 81% of patients who received budesonide compared to 17% of patients who received placebo (P < 0.00001). The pooled odds ratio for clinical response to treatment with budesonide was 12.32 (95% CI 5.53 to 27.46), with a number needed to treat of 2 patients. Statistically significant histological response occurred with treatment in all 3 trials studying budesonide therapy. Eleven patients were enrolled in the trial studying prednisolone (50 mg daily for 2 weeks). Clinical response occurred in 63% of patients who received prednisolone compared to 0% who received placebo (P = 0.15). Twenty-nine patients were enrolled in the trial studying probiotics (2 capsules containing 0.5 x 10(10) CFU each of L. acidophilus LA-5 and B. animalis subsp. lactis strain BB-12 twice daily for 12 weeks). Clinical response occurred in 29% of patients who received probiotics compared to 13% of patients who received placebo (P = 0.38). Twenty-three patients were enrolled in the trial studying mesalamine (800 mg three times daily) with or without cholestyramine (4 g daily) for 6 months. Clinical response occurred in 73% of patients who received mesalamine alone compared to 100% of patients who received mesalamine + cholestyramine (P = 0.14). In maintaining response, 80 patients who had responded to open-label budesonide were enrolled in 2 trials studying budesonide (6 mg daily for 6 months). Clinical response was maintained in 83% of patients who received budesonide compared to 28% of patients who received placebo (P = 0.0002). The pooled odds ratio for maintenance of clinical response to treatment with budesonide was 8.40 (95% CI 2.73 to 25.81), with a number needed to treat of 2 patients. Histological response was maintained in 48% of patients who received budesonide compared to 15% of patients who received placebo (P = 0.002).

AUTHORS' CONCLUSIONS

Budesonide is effective for inducing and maintaining clinical and histological response in patients with collagenous colitis. The evidence for benefit with bismuth subsalicylate and for mesalamine with or without cholestyramine is weak. There is no evidence for the effectiveness of Boswellia serrata extract, prednisolone, or probiotics. These agents and other therapies require further study.