Management of microscopic colitis: challenges and solutions

Bile Acid Sequestrants in Microscopic Colitis: Clinical Outcomes and Utility of Bile Acid Testing

BACKGROUND & AIMS

Bile acid sequestrants (BAS) may be a treatment in microscopic colitis (MC), but efficacy data are limited. We evaluated the effectiveness of BAS in MC and assessed the utility of bile acid testing to predict response.

METHODS

Adults with MC treated with BAS (2010-2020) at Mayo Clinic were identified. Bile acid malabsorption was defined by elevated serum 7⍺-hydroxy-4-cholesten-3-one or by fecal testing using previously validated cutoffs. Response was defined at 12 ± 4 weeks after BAS initiation as: complete (resolution of diarrhea), partial (≥50% improvement in diarrhea), nonresponse (<50% improvement), and intolerance (discontinuation due to side effects). Logistic regression was used to identify predictors of response to BAS.

RESULTS

We identified 282 patients (median age, 59 years [range, 20-87 years]; 88.3% women) with median follow-up of 4.5 years (range, 0.4-9.1 years). Patients were treated with the following BAS: 64.9% cholestyramine, 21.6% colesevelam, and 13.5% colestipol. Clinical outcomes were: 49.3% complete response, 16.3% partial response, 24.8% nonresponse, and 9.6% intolerance. There were no differences in outcomes between those on BAS alone or BAS combined with other medications (P = .98). The dose of BAS was not associated with response (P = .51). Bile acid testing was done in 31.9% of patients, and 56.7% were positive. No predictors of response to BAS were identified. After BAS discontinuation, 41.6% had recurrence at a median of 21 weeks (range, 1-172 weeks).

CONCLUSION

In one of the largest cohorts evaluating BAS treatment in MC, nearly two-thirds had a partial or complete response. Additional research is needed to determine the role of BAS and bile acid malabsorption in MC.

Microscopic Colitis: A Review Article

Microscopic colitis (MC) is a chronic inflammatory disease that affects the older population. Its clinical presentation includes a variety of gastrointestinal manifestations. The main symptom is chronic watery, nonbloody diarrhea. The disease has a female predominance. The diagnosis might be challenging since the symptoms are similar to other differential diagnoses, such as celiac disease, irritable bowel syndrome, Crohn's disease, bacterial overgrowth, and infectious colitis. The golden diagnostic tool for diagnosis is performing colonoscopy to obtain the colonic biopsy, which demonstrates the characteristic histological evidence needed for diagnosis. The treatment starts with an accurate diagnosis and trial of any possible offending medications. Alternatively, there are many medications, such as bismuth or budesonide, which are very effective in treating this disease. The primary objective of this detailed review is to enhance knowledge and understanding of this condition among healthcare providers to guide them with detailed information regarding epidemiology, clinical presentation, diagnosis, and appropriate management. In the assessment of individuals presenting with persistent chronic diarrhea, it is essential for healthcare providers to consider MC as a probable differential diagnosis.

MICROSCOPIC COLITIS: CONSIDERATIONS FOR GASTROENTEROLOGISTS, ENDOSCOPISTS, AND PATHOLOGISTS

•Diagnosis of microscopic colitis necessitates effective communication among gastroenterologists, endoscopists, and pathologists. •The gastroenterologist should refer every patient with chronic watery diarrhea to perform a colonoscopy in spite of the benign course of the disease and the absence of alarm symptoms. •The endoscopist should take 2 or 3 biopsy samples of the colonic mucosa from the right and left colon, put in separate recipients, despite that the mucosa looked macroscopically normal. •The pathologist should be encouraged to use objective histological criteria to make the diagnosis. Microscopic colitis is a chronic inflammatory bowel disease characterized by non-bloody diarrhea that can range from mild to severe. It is difficult to attribute up to 10-20% of chronic diarrhea to microscopic colitis. The three determinants factors of the diagnosis are characteristic clinical symptoms, normal endoscopic picture of the colon, and pathognomonic histological picture. This manuscript aimed to update considerations and recommendations for professionals involved (gastroenterologist, endoscopists and pathologist) in the diagnosis of MC. In addition, a short recommendation about treatment.

Reduced Intake of Dietary Tryptophan Improves Beneficial Action of Budesonide in Patients with Lymphocytic Colitis and Mood Disorders

Lymphocytic colitis (LC) is a gastrointestinal (GI) tract disease with poorly known pathogenesis, but some environmental and lifestyle factors, including certain dietary components, may play a role. Tryptophan is an essential amino acid, which plays important structural and functional roles as a component of many proteins. It is important in the development and maintenance of the body, in which it is metabolized in two main pathways: kynurenine (KYN) and serotonin. In this work, we explored the effect of reducing of TRP in the diet of patients with LC with mood disorders. We enrolled 40 LC patients who had a normal diet, 40 LC patients with the 8-week diet with TRP content reduced by 25% and 40 controls. All LC patients received budesonide at 9 mg per day, and the severity of their GI symptoms was evaluated by the Gastrointestinal Symptoms Rating Scale. Mood disorders were evaluated by the Hamilton Anxiety Rating Scale (HAM-A) and the Hamilton Depression Rating Scale (HAM-D). The concentration of TRP and its metabolites, 5-hydroxyindoleacetic acid (5-HIAA), kynurenine (KYN), kynurenic acid (KYNA) and quinolinic acid (QA), in urine were determined. Budesonide improved the GI and mental states of LC patients, and the diet with reduced TRP content further amended these symptoms. Dietary intervention decreased the concentration of 5-HIAA by about 50% (3.4 vs. 6.3) and QA by about 45% (3.97 vs. 7.20). These changes were correlated with a significant improvement in the profitable action of budesonide on gastrointestinal and mental health of LC patients as they displayed significantly lower GSRS, HAM-A and HAM-B scores after than before the intervention—10.5 vs. 32, 11.0 vs. 21 and 12 vs. 18, respectively. In conclusion, a reduction in TRP intake in diet may improve GI and mental symptoms in LC patients treated with budesonide and these changes may be mediated by the products of TRP metabolism.

Efficacy and safety of medical therapies in microscopic colitis: a systematic review and network meta-analysis

Background

The mainstay of treatment for microscopic colitis (MC) is budesonide. However, the optimal formulation and dosage of budesonide to induce and maintain remission has not yet been clearly demonstrated.

Objectives

To compare the data for efficacy and safety of treatments to induce and maintain remission for MC.

Design

We conducted a meta-analysis of randomised controlled trials (RCTs) comparing treatment with each other or placebo for induction and maintenance of clinical and histological remission in MC.

Data sources and methods

We searched MEDLINE (1946 to May 2021), EMBASE and EMBASE Classis (1947 to May 2021), the Cochrane central register of controlled trials (Issue 2, May 2021) and conference proceedings between 2006 and 2020. Results were reported as pooled relative risks (RRs) with 95% confidence intervals (CIs) to summarise the effect of each comparison tested, with treatments ranked according to p score.

Results

We identified 15 RCTs in total for the treatment of MC. Entocort 9 mg ranked first for clinical (RR: 4.89, CI: 2.43-9.83; p score: 0.86) and histological (RR: 13.39, CI: 1.92-93.44; p score 0.94) induction of remission, whilst VSL#3 ranked second for clinical induction (RR: 5.30, CI: 0.68-41.39; p score 0.81). Budenofalk 6 mg/3 mg alternate day dosing ranked first for clinical maintenance of remission (RR: 3.68, CI: 0.08-159.92, p-score 0.65). Entocort and Budenofalk were associated with the greatest adverse events for induction and maintenance of clinical remission, respectively, although the overall withdrawal numbers for treatment versus placebo groups were 10.9% (22/201) and 10.5% (20/190), respectively.

Conclusion

Entocort 9 mg/day ranked first among the treatment options in inducing remission and Budenofalk 6 mg/3 mg alternate day dosing for maintaining remission in the treatment of MC. Moving forward, mechanistic studies exploring the differences between Entocort and Budenofalk would be valuable whilst future RCT studies are needed in non-corticosteroidal maintenance, particularly looking into immunomodulators, biologics and probiotics.

Microscopic colitis: an update

Microscopic colitis (MC) is an inflammatory pathology of the bowel diagnosed predominantly in older patients. MC is a cause of chronic watery, non-bloody diarrhea, that affects the older patients, mostly women, and leads to impaired health-related quality of life. The diagnosis and treatment can be often difficult. There are three main histological subtypes: collagenous colitis, lymphocytic colitis and incomplete microscopic colitis. Because of the variable nature of this pathology, the therapeutic options should be individualized for every patient. MC has a variable course, varying from occasional symptoms to recurrent or progressive symptoms. A literature search was performed on the main databases. Data on microscopic colitis was collected and presented. This comprehensive review aims to raise awareness of this pathology while providing the latest data regarding current recommendations. General practitioners and gastroenterologists should always take microscopic colitis into consideration when diagnosing a patient with chronic diarrhea.

Budesonide Maintenance in Microscopic Colitis: Clinical Outcomes and Safety Profile From a Population-Based Study

INTRODUCTION

Outcomes and safety of budesonide maintenance therapy in microscopic colitis (MC) are not well known.

METHODS

Adult residents of Olmsted County, Minnesota, diagnosed with MC (2002-2019) and treated with budesonide were identified using the Rochester Epidemiology Project. Response was assessed at 12 ± 4 weeks after initiation of therapy and defined as complete (resolution of diarrhea), partial (≥50% improvement in the number of bowel movements), nonresponse (&lt;50% improvement), and intolerance (discontinued because of side effects). For safety outcomes, cases (budesonide maintenance) and MC controls (no budesonide therapy) were matched by sex and age at diagnosis (±2 years).

RESULTS

A total of 450 patients were identified, of whom 162 (36.0%) were treated with budesonide for induction of clinical remission (median age 67 [23-91] years and 126 women [77.8%] ). Clinical outcomes for induction were as follows: 130 (80.2%) complete response, 22 (13.6%) partial response, 8 (4.9%) no response, and 2 (1.2%) intolerance. After induction, 96 (63.2%) had recurrence after discontinuation, of whom 27 (28.1%) required further budesonide induction treatment without maintenance, 56 (58.3%) required long-term budesonide maintenance, and 13 (13.5%) were treated with other therapies. Of those receiving budesonide maintenance, all responded (55 [98.2%] complete and 1 [1.8%] partial). No patient stopped maintenance from adverse events. The median duration of follow-up was 5.6 years (0.3-18.9). There was no significant difference between cases and controls in the incidence of osteopenia/osteoporosis, diabetes mellitus, hypertension, glaucoma, or cataracts.

DISCUSSION

The long-term use of budesonide in MC seems to be effective and generally well tolerated with limited adverse effects.

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.

A Rare Case of New-Onset Ulcerative Colitis in a Nonagenarian

Ulcerative colitis (UC) is one of two major types of inflammatory bowel disease (IBD). It is defined as a chronic idiopathic inflammatory disease limited to the colorectal mucosal layer and characterized by relapsing and remitting episodes of inflammation. UC almost invariably involves the rectum and extends proximally in a continuous distribution to part or the entire colon. Development of disease after 75 years of age is uncommon, with new-onset over the age of 80 accounting only for 1% of all new diagnoses. We present a case of a new onset UC in a 90-year-old patient presenting with painless hematochezia.

Proctocolectomy and ileal pouch-anal anastomosis for the treatment of collagenous colitis

The role of surgery for collagenous colitis (CC) is unexplored. Either diverting stoma, subtotal colectomy with ileo-rectal anastomosis, and proctocolectomy with ileal pouch-anal anastomosis (IPAA) have been proposed. However, the optimal surgical strategy still needs to be defined. The aim of this short report is to report our experience with two cases of IPAA for CC. Two patients affected by histologically proven CC with watery diarrhea refractory to several lines of medical treatment underwent a laparoscopic proctocolectomy with IPAA at a tertiary referral hospital for the treatment of Inflammatory Bowel Disease in Belgium. A longer rectal cuff was left in place because of the absence of macroscopic inflammation of the rectal mucosa and the consequent negligible risk of cuffitis. No postoperative complications (90 days) occurred. Definitive pathological examination confirmed the diagnosis of CC. At six months, pouchoscopy revealed no signs of inflammation. One year after surgery, mean Öresland and Pouch Functional Score were 10.5 (8-13) and 11.5 (9-14). Functional outcomes after IPAA for CC were barely satisfactory. A high stool frequency not responding to high doses of anti-diarrheals was observed. This has also previously been reported for CC patients receiving a diverting stoma. Proctocolectomy and IPAA for medical refractory CC leads to acceptable short-term gastrointestinal functional outcomes which seems to be particularly affected by high stool frequency. For this reason, pouch surgery might not be the optimal indication for collagenous colitis.

Analysis of Clinical and Histopathological Findings in Microscopic Colitis

OBJECTIVE

Microscopic colitis is a chronic inflammatory disorder characterized by a triad of chronic diarrhea, endoscopy without significant abnormality, and distinct histopathological features. Histopathologically, microscopic colitis is divided into 3 subtypes; collagenous colitis, lymphocytic colitis, incomplete microscopic colitis. The main purpose of this study was to analyze the detailed clinicopathological parameters of microscopic colitis cases in the Turkish population.

MATERIAL AND METHOD

The clinicopathological parameters were evaluated in 53 microscopic colitis cases (37 collagenous colitis, 7 lymphocytic colitis, 9 incomplete microscopic colitis) diagnosed between 2010 and 2019.

RESULTS

All cases had lymphoplasmacytosis. The presence of ≥20 eosinophils/high power field in the lamina propria was remarkable in 75.7%, 57.1%, and 11.1% of collagenous colitis, lymphocytic colitis, and incomplete microscopic colitis cases, respectively. One of the striking findings was the presence of concomitant Celiac disease in 29% of the lymphocytic colitis cases. In terms of drug use, proton pump inhibitors and nonsteroidal anti-inflammatory drugs were the most commonly used drugs.

CONCLUSION

The mean age in our series is lower than the literature and a distinct male predominance was observed in lymphocytic colitis and incomplete microscopic colitis, contrary to the literature. These suggest that susceptibility to microscopic colitis may differ between ethnic groups. The presence of overt lymphoplasmacytosis, eosinophilic infiltration and epithelial damage are the microscopic features which should alert the pathologist for the diagnosis of complete microscopic colitis. Given that microscopic colitis is a common treatable cause of chronic diarrhea, awareness of the aforementioned histopathological features is of utmost importance for accurate diagnosis and not to miss incomplete cases.

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.

Medication use and microscopic colitis

BACKGROUND

Microscopic colitis is an increasingly common cause of watery diarrhoea. Several classes of medications have been associated with microscopic colitis in prior studies.

AIMS

To determine the association between the use of previously implicated medications and microscopic colitis.

METHODS

This was a case-control study of patients referred for elective, outpatient colonoscopy for diarrhoea. Patients were excluded for inflammatory bowel disease, C difficile, or other infectious diarrhoea. Colon biopsies were reviewed by the study pathologist and patients were classified as microscopic colitis cases or non-microscopic colitis controls.

RESULTS

The study population included 110 microscopic colitis cases and 252 controls. The cases were older, better educated and more likely to be female. Cases reported a greater number of loose, watery, or liquid stools, nocturnal stools, more urgency and weight loss compared to controls. There was no association with proton pump inhibitors (PPIs), adjusted OR (aOR) 0.66, 95% CI 0.38-1.13 or nonsteroidal anti-inflammatory drugs, aOR 0.68, 95% CI 0.40-1.17. Cholecystectomy was less common in cases, aOR 0.33, 95% CI 0.17-0.64, but microscopic colitis cases had more frequent bowel movements following cholecystectomy.

CONCLUSION

Compared to similar patients with diarrhoea, cases with microscopic colitis were not more likely to have taken previously implicated medications. They had more diarrhoea following cholecystectomy, suggesting that bile may play a role in symptoms or aetiology. We conclude that the appropriate choice of controls is crucial to understanding risk factors for microscopic colitis.

Anti-PD-1 induced collagenous colitis in metastatic melanoma: a rare severe adverse event

Immunotherapy has improved the overall survival of patients with metastatic melanoma. Inflammatory bowel disease-like colitis is the most frequent gastrointestinal serious adverse event in patients treated with immune-checkpoint inhibitors. Collagenous colitis is microscopic colitis. Only two cases of immune-checkpoint inhibitors induced collagenous colitis have been reported. A man in his early 70s was referred for a metastatic melanoma treated with nivolumab as the fourth line of treatment. During the 21st cycle, the patient complained of watery, nonbloody diarrhea (around six times per day). Rectosigmoidoscopy showed no mucosal lesion. A thickened subepithelial collagen band was evidenced by trichrome staining, which was suggestive of collagenous colitis. Nivolumab was stopped and the patient was treated with budesonide 9 mg/day in combination with loperamide and cholestyramine, leading to improvement of diarrhea. However, worsening of digestive symptoms during tapering of corticosteroid dose required the permanent discontinuation of nivolumab. Due to the very low number of cases reported to date and their different evolution under corticosteroids, it is not clear whether or not immune checkpoint inhibitors can be restarted in these patients.

Transcriptomic Profiling of Collagenous Colitis Identifies Hallmarks of Nondestructive Inflammatory Bowel Disease

BACKGROUND AND AIMS

The pathophysiology of the inflammatory bowel disease collagenous colitis (CC) is poorly described. Our aim was to use RNA sequencing of mucosal samples from patients with active CC, CC in remission, refractory CC, ulcerative colitis (UC), and control subjects to gain insight into CC pathophysiology, identify genetic signatures linked to CC, and uncover potentially druggable disease pathways.

METHODS

We performed whole transcriptome sequencing of CC samples from patients before and during treatment with the corticosteroid drug budesonide, CC steroid-refractory patients, UC patients, and healthy control subjects (n = 9-13). Bulk mucosa and laser-captured microdissected intestinal epithelial cell (IEC) gene expression were analyzed by gene set enrichment and gene set variation analyses to identify significant pathways and cells, respectively, altered in CC. Leading genes and cells were validated using reverse-transcription quantitative polymerase chain reaction or immunohistochemistry.

RESULTS

We identified an activation of the adaptive immune response to bacteria and viruses in active CC that could be mediated by dendritic cells. Moreover, IECs display hyperproliferation and increased antigen presentation in active CC. Further analysis revealed that genes related to the immune response (DUOX2, PLA2G2A, CXCL9), DNA transcription (CTR9), protein processing (JOSD1, URI1), and ion transport (SLC9A3) remained dysregulated even after budesonide-induced remission. Budesonide-refractory CC patients fail to restore normal gene expression, and displayed a transcriptomic profile close to UC.

CONCLUSIONS

Our study confirmed the implication of innate and adaptive immune responses in CC, governed by IECs and dendritic cells, respectively, and identified ongoing epithelial damage. Refractory CC could share pathomechanisms with UC.

Novel Case Report: A Previously Reported, but Pathophysiologically Unexplained, Association Between Collagenous Colitis and Protein-Losing Enteropathy May Be Explained by an Undetected Link with Collagenous Duodenitis

Collagenous colitis (CC) is associated with non-bloody, watery diarrhea, which is pathophysiologically reasonable because normal colonic absorption (or excretion) of water and electrolytes can be blocked by the abnormally thick collagen layer in CC. However, CC has also been associated with six previous cases of protein-losing enteropathy (PLE), with no pathophysiologic explanation. The colon does not normally absorb (or excrete) amino acids/proteins, which is primarily the function of the small bowel. Collagenous duodenitis (CD) has not been associated with PLE. This work reports a novel case of CD (and CC) associated with PLE; a pathophysiologically reasonable mechanism for CD causing PLE (by the thick collagen layer of CD blocking normal intestinal amino acid absorption); and a novel association of PLE with severe COVID-19 infection (attributed to relative immunosuppression from hypoproteinemia, hypoalbuminemia, hypogammaglobulinemia, and malnutrition from PLE).

Incidence and Prevalence of Microscopic Colitis Between 2001 and 2016: A Danish Nationwide Cohort Study

BACKGROUND AND AIMS

Epidemiological studies suggest an increasing global incidence of microscopic colitis, including collagenous colitis and lymphocytic colitis. We aimed to investigate the incidence and prevalence of microscopic colitis in Denmark.

METHODS

In a nationwide cohort study, we included all incident patients with a recorded diagnosis of collagenous colitis or lymphocytic colitis in the Danish Pathology Register between 2001 and 2016.

RESULTS

A total of 14 302 patients with microscopic colitis-8437 [59%] with collagenous and 5865 [41%] with lymphocytic colitis-were identified during the study period. The prevalence in December 2016 was estimated to be 197.9 cases per 100 000 inhabitants. Microscopic colitis was more prevalent among females (n = 10 127 [71%]), with a mean annual incidence of 28.8, compared with 12.3 per 100 000 person-years among males. The overall mean incidence during the study period was 20.7 per 100 000 person-years. Mean age at time of diagnosis was 65 years (standard deviation [SD]:14) for microscopic colitis, 67 [SD:13] for collagenous colitis, and 63 [SD:15] for lymphocytic colitis. The overall incidence increased significantly from 2.3 cases in 2001 to 24.3 cases per 100 000 person-years in 2016. However, the highest observed incidence of microscopic colitis was 32.3 cases per 100 000 person-years in 2011. Large regional differences were found, with the highest incidence observed in the least populated region.

CONCLUSIONS

The incidence of microscopic colitis in Denmark has increased 10-fold during the past 15 years and has now surpassed that of Crohn's disease and ulcerative colitis. However, incidence has stabilised since 2012, suggesting that a plateau has been reached.