Microscopic colitis

Rheumatologic Associations of Microscopic Colitis: A Narrative Review

Extra-intestinal manifestations are frequent complications of the classical inflammatory bowel diseases, Crohn's disease and ulcerative colitis. However, in addition to the classical diseases, there is a spectrum of conditions, often termed "microscopic colitis", in which extra-intestinal manifestations are less well described. Our objective was to review the literature regarding the extra-intestinal manifestations complicating microscopic colitis and describe the association with systemic autoimmune rheumatic diseases. A comprehensive search and review of peer-reviewed English-language and international journals and reports was completed based on key terms, including "microscopic colitis", "lymphocytic colitis", "collagenous colitis", "inflammatory bowel disease", "extraintestinal manifestations", and the specific disease associations utilizing the PubMed Central database and MEDLINE. A broad spectrum of rheumatologic manifestations has been reported in patients with microscopic colitis. The identification of rheumatoid arthritis and limited scleroderma as co-morbidities with microscopic colitis was noteworthy. Inflammatory arthropathy was frequently seen in microscopic colitis, usually preceding or occurring in conjunction with the onset of gastrointestinal symptoms. A variety of presentations of associated arthritis were reported: migratory, symmetric or asymmetric, peripheral or axial, oligoarticular or polyarticular, erosive or non-erosive. There was a high incidence of autoantibodies in these patients, supporting a potential autoimmune association. On the basis of these anecdotal reports, we would suggest development of a clinical registry to help define the incidence of extra-intestinal manifestations and systemic autoimmune rheumatic diseases among microscopic colitis patients to help elucidate shared predispositions, pathogenic mechanisms and therapeutic opportunities.

Collagenous colitis in a child induced by chronic respiratory allergy: A case report

INTRODUCTION

Collagen colitis (CC) is a microscopic colitis diagnosed by mucosal biopsy and is extremely rare in children.

PATIENT CONCERNS

We reported a child with severe persistent diarrhea that could not be relieved with traditional diarrheal treatment. No abnormalities were found after multiple colonoscopies.

DIAGNOSES

A significant increase in total IgE levels was found in the patient's blood. He had a history of mild chronic allergic rhinitis and slightly intermittent wheezing. However, we found that the child had a hyperallergic reaction to multiple respiratory antigens and had mild pulmonary dysfunction. Finally, colonoscopy with biopsy identified the diagnosis of CC.

INTERVENTION

Considering that a respiratory allergic reaction was one of the causes of diarrhea, anti-allergic treatment was given to the child, and his severe diarrhea was soon relieved. Corticosteroid treatment was suggested to the patient, but his parents firmly refused steroid therapy. According to the patient's specific allergic reaction to mites, desensitization treatment was finally chosen for him.

OUTCOMES

After 1 year of desensitization for dust mites, the patient's respiratory symptoms improved, total IgE levels decreased, autoantibodies declined, and diarrhea did not reoccur. Colonoscopy with biopsy showed a significant improvement in pathology.

CONCLUSION

CC in children is rare, and childhood CC induced by a respiratory allergic reaction has not been previously reported. Therefore, this is a special case of CC in a patient who was cured with anti-allergy treatments and desensitization instead of steroid therapy.

Validating microscopic colitis (MC) in Swedish pathology registers

OBJECTIVE

Microscopic colitis (MC), encompassing collagenous colitis (CC) and lymphocytic colitis (LC), is a diagnosis which relies on histopathologic criteria. This report examines the validity of having a diagnosis of MC in Swedish pathology registers.

METHODS

We reviewed patient charts from 215 randomly selected individuals from 15 pathology departments in five healthcare regions in Sweden with a relevant histopathology code for MC on colon biopsies. Information on clinical symptoms and laboratory data were obtained from medical chart review. We obtained sufficient data on 211 individuals for calculating positive predictive values (PPVs) for MC.

RESULTS

In total, 200/211 patients with a histopathology diagnosis of MC were confirmed as also having a clinical diagnosis of MC after chart review, yielding a PPV of 95% (95%CI =91-97%). The PPV for CC was 95% (95%CI =87-98%) and 85% for LC (95%CI =78-90%). The median age at biopsy was 67 years (range 17-90 years), and 72% (n = 154) were women. The most common symptoms in patients with MC histopathology were diarrhea (96% of patients), weight loss (24%) and abdominal pain (13%). Four percent (4/111) of patients with available data on stool culture were positive for gastrointestinal pathogens (none had Clostridium difficile). In 81 patients with available celiac serology, five (6%) were positive. Twenty-six percent of all patients had at least one other autoimmune disease, the most frequent being hypothyroidism (8%) and celiac disease (6%).

CONCLUSIONS

This study found a high validity for MC as recorded in Swedish pathology registers.

Microscopic colitis-microbiome, barrier function and associated diseases

Microscopic colitis (MC) is a chronic inflammatory bowel disease (IBD) with little in terms of endoscopic abnormalities and is frequently associated with other autoimmune diseases. The peak incidence of the disease is in middle aged or older populations, mostly females. The pathogenesis of MC is complex, multifactorial and poorly understood. Current concepts revolve around innate immunity or microbiome alterations as well as gut barrier dysfunction, all of which lead to the development of subtle inflammatory lesions in gut mucosa. The results of numerous basic and clinical studies involving molecular techniques as well as advanced endoscopic imaging revealed the important role of both intrinsic (e.g., hormonal) as well as extrinsic (e.g., NSAIDs and PPIs) factors in the modulation of gastrointestinal microbiome and MC pathogenesis. Capsule endoscopy as well confocal endomicroscopy imaging, alongside standard endoscopic techniques offer new tools in the evaluation of MC patients and allow their better stratification for novel treatment protocols based on modulation of gut microbiome and barrier function.

Interventions for treating lymphocytic colitis

BACKGROUND

Lymphocytic colitis is a cause of chronic diarrhea. It is a subtype of microscopic colitis characterized by chronic, watery, non-bloody diarrhea and normal endoscopic and radiologic findings. The etiology of this disorder is unknown.Therapy is based mainly on case series and uncontrolled trials, or by extrapolation of data for treating collagenous colitis, a related disorder. This review is an update of a previously published Cochrane review.

OBJECTIVES

To evaluate the efficacy and safety of treatments for clinically active lymphocytic colitis.

SEARCH METHODS

The MEDLINE, PUBMED and EMBASE databases were searched from inception to 11 August 2016 to identify relevant papers. Manual searches from the references of included studies and relevant review articles were performed.Abstracts from major gastroenterological meetings were also searched to identify research submitted in abstract form only. The trial registry web site www.ClinicalTrials.gov was searched to identify registered but unpublished trials. Finally, the Cochrane Central Register of Controlled Trials and the Cochrane Inflammatory Bowel Disease and Functional Bowel Disorders Group Specialized Trials Register were searched for other studies.

SELECTION CRITERIA

Randomized controlled trials assessing medical therapy for patients with biopsy-proven lymphocytic colitis were considered for inclusion DATA COLLECTION AND ANALYSIS: Data was independently extracted by at least two authors. Any disagreements were resolved by consensus. Data were analyzed on an intention-to-treat (ITT) basis. The primary outcome was clinical response as defined by the included studies. Secondary outcome measures included histological response as defined by the included studies, quality of life as measured by a validated instrument and the occurrence of adverse events. Risk ratios (RR) and 95% confidence intervals (CI) were calculated for dichotomous outcomes. The methodological quality of included studies was evaluated using the Cochrane risk of bias tool. The overall quality of the evidence supporting the primary outcome and selected secondary outcomes was assessed using the GRADE criteria. Data were combined for analysis if they assessed the same treatments. Dichotomous data were combined using a pooled RR along with corresponding 95% CI. A fixed-effect model was used for the pooled analysis.

MAIN RESULTS

Five RCTs (149 participants) met the inclusion criteria. These studies assessed bismuth subsalicylate versus placebo, budesonide versus placebo, mesalazine versus mesalazine plus cholestyramine and beclometasone dipropionate versus mesalazine. The study which assessed mesalazine versus mesalazine plus cholestyramine and the study which assessed beclometasone dipropionate versus mesalazine were judged to be at high risk of bias due to lack of blinding. The study which compared bismuth subsalicylate versus us placebo was judged as low quality due to a very small sample size and limited data. The other 3 studies were judged to be at low risk of bias. Budesonide (9 mg/day for 6 to 8 weeks) was significantly more effective than placebo for induction of clinical and histological response. Clinical response was noted in 88% of budesonide patients compared to 38% of placebo patients (2 studies; 57 participants; RR 2.03, 95% CI 1.25 to 3.33; GRADE = low). Histological response was noted in 78% of budesonide patients compared to 33% of placebo patients (2 studies; 39 patients; RR 2.44, 95% CI 1.13 to 5.28; GRADE = low). Forty-one patients were enrolled in the study assessing mesalazine (2.4 g/day) versus mesalazine plus cholestyramine (4 g/day). Clinical response was noted in 85% of patients in the mesalazine group compared to 86% of patients in the mesalazine plus cholestyramine group (RR 0.99, 95% CI 0.77 to 1.28; GRADE = low). Five patients were enrolled in the trial studying bismuth subsalicylate (nine 262 mg tablets daily for 8 weeks versus placebo). There were no differences in clinical (P=0.10) or histological responses (P=0.71) in patients treated with bismuth subsalicylate compared with placebo (GRADE = very low). Forty-six patients were enrolled in the trial studying beclometasone dipropionate (5 mg/day or 10 mg/day) versus mesalazine (2.4 g/day). There were no differences in clinical remission at 8 weeks (RR 0.97; 95% CI 0.75 to 1.24; GRADE = low) and 12 months of treatment (RR 1.29; 95% CI 0.40 to 4.18; GRADE = very low). Although patients receiving beclometasone dipropionate (84%) and mesalazine (86%) achieved clinical remission at 8 weeks, it was not maintained at 12 months (26% and 20%, respectively). Adverse events reported in the budesonide studies include nausea, vomiting, neck pain, abdominal pain, hyperhidrosis and headache. Nausea and skin rash were reported as adverse events in the mesalazine study. Adverse events in the beclometasone dipropionate trial include nausea, sleepiness and change of mood. No adverse events were reported in the bismuth subsalicylate study.

AUTHORS' CONCLUSIONS

Low quality evidence suggests that budesonide may be effective for the treatment of active lymphocytic colitis. This benefit needs to be confirmed by a large placebo -controlled trial. Low quality evidence also suggests that mesalazine with or without cholestyramine and beclometasone dipropionate may be effective for the treatment of lymphocytic colitis, however this needs to be confirmed by large placebo-controlled studies. No conclusions can be made regarding bismuth subsalicylate due to the very small number of patients in the study, Further trials studying interventions for lymphocytic colitis are warranted.

Automated image analysis in the study of collagenous colitis

PURPOSE

The aim of this study was to develop an automated image analysis software to measure the thickness of the subepithelial collagenous band in colon biopsies with collagenous colitis (CC) and incomplete CC (CCi). The software measures the thickness of the collagenous band on microscopic slides stained with Van Gieson (VG).

PATIENTS AND METHODS

A training set consisting of ten biopsies diagnosed as CC, CCi, and normal colon mucosa was used to develop the automated image analysis (VG app) to match the assessment by a pathologist. The study set consisted of biopsies from 75 patients. Twenty-five cases were primarily diagnosed as CC, 25 as CCi, and 25 as normal or near-normal colonic mucosa. Four pathologists individually reassessed the biopsies and categorized all into one of the abovementioned three categories. The result of the VG app was correlated with the diagnosis provided by the four pathologists.

RESULTS

The interobserver agreement for each pair of pathologists ranged from κ-values of 0.56-0.81, while the κ-value for the VG app vs each of the pathologists varied from 0.63 to 0.79. The overall agreement between the four pathologists was κ=0.69, while the overall agreement between the four pathologists and the VG app was κ=0.71.

CONCLUSION

In conclusion, the Visiopharm VG app is able to measure the thickness of a sub-epithelial collagenous band in colon biopsies with an accuracy comparable to the performance of a pathologist and thereby provides a promising supplementary tool for the diagnosis of CC and CCi and in particular for research.