Microscopic Colitis and Risk of Incident Psoriasis: A Nationwide Population-Based Matched Cohort Study

Background

Microscopic colitis (MC) has been associated with several immune-mediated diseases including psoriasis, but earlier research has been limited to psoriasis occurring before MC. Data from large-scale cohort studies investigating MC and risk of future psoriasis are lacking.

Objective

To examine the association between MC and psoriasis.

Methods

In a nationwide, population-based, matched cohort study in Sweden from 2007 to 2021, we identified 8404 patients with biopsy-verified MC (diagnosed in 2007-2017), 37,033 matched reference individuals, and 8381 siblings without MC. Information on MC was obtained through the ESPRESSO cohort (a Swedish histopathology database with nationwide coverage). Using Cox regression, we calculated hazard ratios (HRs) and 95% confidence intervals (CIs) for psoriasis up until 2021.

Results

During a median follow-up of 9.2 years (interquartile range = 6.7-11.7), 179 MC patients and 440 reference individuals were diagnosed with psoriasis (241.1 vs 131.8 events per 100,000 person-years), corresponding to one extra case of psoriasis in 91 patients with MC over 10 years. After adjustment for the matching variables (birth year, sex, county of residence, and calendar period) and level of education, we computed an adjusted hazard ratio (aHR) of 1.82 (95% CI = 1.53-2.17). Stratified by sex, estimates were similar and when examining the aHR across different lengths of follow-up, we found significantly elevated estimates up to 10 years after MC diagnosis. Compared to MC-free siblings, the aHR was 1.85 (95% CI = 1.36-2.51).

Conclusion

Patients with MC are at an almost doubled risk of psoriasis compared to the general population. Clinicians need to consider psoriasis in MC patients with skin lesions.

The association between drugs and repeated treatment with budesonide in patients with microscopic colitis: a retrospective observational study

Background

Smoking and the use of non-steroidal anti-inflammatory drugs (NSAIDs) acetylsalicylic acid (ASA), proton pump inhibitors (PPIs), serotonin reuptake inhibitors (SSRIs), and statins have been associated with microscopic colitis (MC).

Objectives

We investigated whether these factors were associated with repeated budesonide treatments in patients diagnosed with MC.

Design

Retrospective observational study.

Methods

All patients with a histologically verified diagnosis of MC at our clinic between the years 2006 and 2022 were identified. Baseline factors and drugs prescribed before and after diagnosis were registered. The influence of risk factors on the odds of having a prescription of oral budesonide and the odds of having a second course of budesonide was studied.

Results

Patients with MC (n = 183) with a mean age of 62.3 years [standard deviation (SD): 13.3 years] were followed for a median of 5 years (25th-75th percentile 4-10 years) after diagnosis. In all, 138 patients (75%) had at least one prescription of budesonide after diagnosis, and 90 patients (49%) had at least one clinical relapse treated with budesonide. Patients who had been prescribed NSAIDs within 1 year before clinical relapse had higher odds for clinical relapse [odds ratio (OR): 3.70, 95% confidence interval (CI): 1.06-12.9] but there was no increased risk for clinical relapse for the use of ASA (OR: 0.99, 95% CI: 0.39-2.90), PPIs (OR: 1.09, 95% CI: 0.45-2.63), SSRI (OR: 1.41, 95% CI: 0.82-2.44), or statins (OR: 0.83, 95% CI: 0.35-1.99). No association was seen between being a smoker and/or being prescribed NSAID, ASA, PPI, SSRI, and statins at baseline and the odds of having a prescription of oral budesonide within 1 year after diagnosis.

Conclusion

The risk of being prescribed a second course of budesonide is associated with receiving a prescription of NSAIDs but not with the use of ASA, PPIs, SSRIs, and statins.

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.

Lymphocytic colitis can be transcriptionally divided into channelopathic and inflammatory lymphocytic colitis

BACKGROUND

The pathobiology of the non-destructive inflammatory bowel disease (IBD) lymphocytic colitis (LC) is poorly understood. We aimed to define an LC-specific mucosal transcriptome to gain insight into LC pathology, identify unique genomic signatures, and uncover potentially druggable disease pathways.

METHODS

We performed bulk RNA-sequencing of LC and collagenous colitis (CC) colonic mucosa from patients with active disease, and healthy controls (n = 4-10 per cohort). Differential gene expression was analyzed by gene-set enrichment and deconvolution analyses to identify pathologically relevant pathways and cells, respectively, altered in LC. Key findings were validated using reverse transcription quantitative PCR and/or immunohistochemistry. Finally, we compared our data with a previous cohort of ulcerative colitis and Crohn's disease patients (n = 4 per group) to distinguish non-destructive from classic IBD.

RESULTS

LC can be subdivided into channelopathic LC, which is governed by organic acid and ion transport dysregulation, and inflammatory LC, which is driven by microbial immune responses. Inflammatory LC displays an innate and adaptive immunity that is limited compared to CC and classic IBD. Conversely, we noted a distinct induction of regulatory non-coding RNA species in inflammatory LC samples. Moreover, compared with CC, water channel and cell adhesion molecule gene expression decreased in channelopathic LC, whereas it was accentuated in inflammatory LC and associated with reduced intestinal epithelial cell proliferation.

CONCLUSIONS

We conclude that LC can be subdivided into channelopathic LC and inflammatory LC that could be pathomechanistically distinct subtypes despite their shared clinical presentation. Inflammatory LC exhibits a dampened immune response compared to CC and classic IBDs. Our results point to regulatory micro-RNAs as a potential disease-specific feature that may be amenable to therapeutic intervention.

Collagenous Colitis with Escitalopram Use: A Case Report and Literature Review

We present the case of a 42-year-old female whose escitalopram use potentially contributed to a diagnosis of collagenous colitis. The patient presented with significant watery, nonbloody diarrhea, abdominal cramping and pain, and weight loss. Established risk factors of microscopic colitis in this patient include a history of smoking and female gender. The patient underwent a colonoscopy, which confirmed histological changes consistent with collagenous colitis. Prescribed therapy included oral budesonide and omeprazole, continued for eight and twelve weeks, respectively. Escitalopram was continued, with a discussion regarding changing to an alternative therapy. Based on the patient's history of escitalopram use, this case suggests a relationship between escitalopram and microscopic colitis. Though case reports of patients diagnosed with microscopic colitis after antidepressant use are published, this case appears to be the only report of collagenous colitis without macroscopic complications following escitalopram use. This case adds further support in that antidepressants may contribute to microscopic colitis. Despite an undefined frequency of association, healthcare providers who prescribe antidepressants should be cognizant of the theorized association and understand risk factors, screening, and treatment approaches.

Concomitant Lymphocytic Colitis With Recurrent Clostridium difficile Infection

Microscopic colitis is a clinicopathological diagnosis that is characterized by chronic microscopic inflammation of the colon and presents with chronic watery diarrhea. There are following two subtypes of microscopic colitis: lymphocytic colitis and collagenous colitis. This is a case of a 70-year-old female with a history of Clostridium difficile infections who presented with persistent watery diarrhea and was diagnosed with lymphocytic colitis in the setting of a concomitant C. difficile infection. Given her clinical presentation, the patient was initiated on empiric treatment for C. difficile infection and showed a lack of clinical improvement with persistent watery diarrhea and elevated white blood cell count. The patient's symptoms resolved upon the confirmatory diagnosis and treatment of lymphocytic colitis. This study illustrates the importance of assessing for, diagnosing, and treating lymphocytic colitis in patients with chronic non-resolving watery diarrhea, especially in the setting of concomitant or recurrent C. difficile infections. Additionally, it emphasizes the need for further characterization of the relationship between C. difficile infection and microscopic colitis.

A Literature Review of Microscopic Colitis

Although the clinical importance of microscopic colitis (MC) is highly increasing, however, the disease is still mysterious due to several challenges. Recent MC data depend mainly on doubts and uncertainties leading to misclassification. This review discussed the current knowledge gaps about MC and various controversies regarding its subtypes, pathogenesis, and management. The diagnosis of MC is based mainly on histology and immunohistopathology which can discriminate two subtypes. However, transitional forms are often associated with misclassification. The site and number of the colon biopsies have been agreed upon as at least three from each side of the colon (right and left) with a total of six. There is no credible, clear explanation for the increased incidence. The etiopathogenesis is possibly multifactorial with a high impact on the immunological background. It is proposed that MC would be the initiative of irritable bowel disease, which needs further data clarification. Although budesonide is an effective treatment in most cases, budesonide-refractory MC represents a significant clinical challenge. Therefore, immunomodulators and biologics are now well-thought to be the second-line choice for treatment.

Microscopic Colitis in a Young Male: Unveiling the Rarity

In recent decades, microscopic colitis (MC) has become increasingly recognized as a common contributor to diarrhea and lower gastrointestinal symptoms, particularly among the older demographic. The condition is distinguished by persistent diarrhea with loose watery stools, and endoscopic examination is typically normal with characteristic histopathologic findings. MC is rarely seen under 30 years of age and is less common in males. Our case highlights an exceedingly uncommon clinical setting as it involves a young male who was diagnosed with collagenous colitis. The diagnosis of MC can easily be missed by physicians during initial evaluation. Specifically in irritable bowel syndrome patients with diarrhea predominant symptoms, a colonoscopy should be performed and biopsies should be taken from the entire colon to rule out MC.

Microscopic colitis and risk of incident rheumatoid arthritis: A nationwide population-based matched cohort study

BACKGROUND

Microscopic colitis (MC) has been linked to several autoimmune conditions. Results from previous studies on the association with rheumatoid arthritis (RA) have been inconsistent.

AIM

To assess the risk of future RA in MC.

METHODS

We conducted a nationwide matched cohort study in Sweden of 8179 patients with biopsy-verified MC (diagnosed in 2007-2017), 36,400 matched reference individuals and 8202 siblings without MC, with follow-up until 2021. Information on MC was obtained from all of Sweden's regional pathology registers (n = 28) through the ESPRESSO cohort. Data on incident RA were collected from the National Patient Register. Using Cox regression, we calculated adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs).

RESULTS

During a median follow-up of 9.1 years (interquartile range = 6.7-11.7), 73 MC patients and 183 reference individuals from the general population were diagnosed with RA (99 vs. 55 events per 100,000 person-years), equivalent to one extra case of RA in 226 patients with MC followed for 10 years. These rates corresponded to an aHR of 1.83 (95% CI = 1.39-2.41). The aHR was highest during the first year of follow-up (2.31 [95% CI = 1.08-4.97]) and remained significantly elevated up to 5 years after MC diagnosis (aHR 2.16; 95% CI = 1.42-3.30). Compared to siblings, without MC, the aHR was 2.04 (95% CI = 1.18-3.56).

CONCLUSION

Patients with MC are at a nearly two-fold risk of developing RA compared to the general population. Knowledge of this increased risk may expedite evaluation for RA in patients with MC presenting with joint symptoms and/or arthralgia, thus preventing delay until RA diagnosis.

Microscopic Colitis and Risk of Incident Acute Pancreatitis: A Nationwide Population-Based Matched Cohort Study

INTRODUCTION

Several gastrointestinal diseases have been linked to acute pancreatitis, but the risk of acute pancreatitis in microscopic colitis (MC) has not been studied.

METHODS

We conducted a nationwide, population-based, matched cohort study in Sweden of 12,140 patients with biopsy-verified MC (diagnosed in 2003-2017), 57,806 matched reference individuals, and 12,781 siblings without MC with a follow-up until 2021. Data on MC were obtained from all of Sweden's regional pathology registers (n = 28) through the ESPRESSO cohort. Data on acute pancreatitis were collected from the National Patient Register. Adjusted hazard ratios (aHR) and 95% confidence intervals (CI) were calculated using Cox regression.

RESULTS

During a mean follow-up of 9.9 years (SD = 4.3), 146 patients with MC and 437 reference individuals were diagnosed with acute pancreatitis (127.8 vs 80.1 per 100,000 person-years), corresponding to an aHR of 1.57 (95% CI = 1.30-1.90). Moreover, we found a positive association between MC and acute nongallstone-related pancreatitis (aHR 1.99 [95% CI = 1.57-2.51]), but not with acute gallstone-related pancreatitis (aHR 1.08 [95% CI = 0.78-1.49]). Comparing patients with MC with their unaffected siblings yielded an aHR of 1.28 (95% CI = 0.92-1.78). The risk of acute pancreatitis remained elevated also for patients with MC with a follow-up exceeding 10 years (aHR 1.75 [95% CI = 1.14-2.67]).

DISCUSSION

This nationwide study of more than 12,000 patients with MC demonstrated an increased risk of acute pancreatitis after MC. Hence, clinicians should have a low threshold for the evaluation of acute pancreatitis in patients with MC. In addition, these patients should receive advice and care aimed at reducing the risk of acute pancreatitis.

Pericardial Effusion as the Initial Presentation of Systemic Lupus Erythematosus in a 37-Year-Old Female

Systemic lupus erythematosus (SLE) is a complex autoimmune disease that can affect various organs and systems in the body, leading to a wide range of clinical manifestations. Pericardial effusion, which is an accumulation of excessive fluid in the pericardial sac surrounding the heart, can be one of the early presentations of SLE in some individuals. When it occurs in young females, it can be particularly concerning, as SLE predominantly affects women of childbearing age. In this case report, we describe pericardial effusion as the initial presentation of SLE in a 37-year-old mother of four children. Importantly, early diagnosis and consistent follow-up are critical for improving the prognosis and quality of life for individuals with SLE.

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.

Misinterpreting Diarrhea-Predominant Irritable Bowel Syndrome and Functional Diarrhea: Pathophysiological Highlights

Irritable bowel syndrome with predominant diarrhea (IBS-D) and functional diarrhea (FD) are disorders of gut-brain interaction characterized by recurring symptoms which have a serious impact on the patient's quality of life. Their pathophysiology is far from being completely understood. In IBS-D growing evidence suggests that bile acid malabsorption (BAM) could be present in up to 30% of patients. Microscopic colitis (MC) is a well-known cause of watery diarrhea and some patients, at first, can be diagnosed as IBS-D or FD. Both BAM and MC are often responsible for the lack of response to conventional treatments in patients labelled as "refractory". Moreover, because BAM and MC are not mutually exclusive, and can be found in the same patient, they should always be considered in the diagnostic workout when a specific treatment for BAM or MC is unsatisfactory. In the present review the possible shared pathogenetic mechanisms between BAM and MC are discussed highlighting how MC can induce a secondary BAM. Moreover, a brief overview of the current literature regarding the prevalence of their association is provided.

Colon perforation due to collagenous colitis: A case report

Collagenous colitis (CC) is generally benign, and serious complications are rare. It is important to note that spontaneous perforation of CC is a possible complication. In the case of colon perforation of unknown origin, CC should be considered.

Effectiveness and Safety Profile of Budesonide Maintenance in Microscopic Colitis: A Systematic Review and Meta-Analysis

BACKGROUND

Microscopic colitis (MC) is a common cause of chronic diarrhea. Randomized controlled trials (RCTs) have demonstrated the efficacy of budesonide treatment for MC. However, relapse is frequent after discontinuation of budesonide, and data on maintenance therapy are limited. We performed a systematic review and meta-analysis evaluating these outcomes in clinical trials and real-world settings.

METHODS

A systematic search was performed on October 31, 2022, of Medline, Embase, Cochrane, and Scopus. Case series, case-control, cohort studies, and RCTs of adults with MC were included. Data were pooled using random effects models to calculate weighted pooled estimates and 95% confidence intervals. Heterogeneity was assessed using the I2 statistic.

RESULTS

We included 35 studies (11 RCTs, 24 observational studies) with 1657 MC patients treated with budesonide induction and 146 for maintenance. The overall pooled clinical remission rate with budesonide treatment was similar between RCTs and observational studies. The pooled remission rate with budesonide maintenance therapy was 84% (95% CI, 0.60-1.00; I2 = 91%). After budesonide discontinuation, the pooled relapse rate was 53% (95% CI, 0.42-0.63; I2 = 76%). On maintenance therapy, no differences were noted in adverse events (eg, metabolic bone disease, hypertension, hyperglycemia, cataracts/glaucoma) in those on budesonide vs placebo or other noncorticosteroid medications for MC (P = .9).

CONCLUSIONS

Budesonide is an effective maintenance treatment for MC. There is a high risk of recurrence after budesonide discontinuation, but long-term use at the lowest effective dose appears to be relatively safe and have limited adverse effects.

Case report: Exploring teduglutide as a therapeutic option for refractory microscopic colitis: insights and implications

Microscopic colitis is a chronic inflammatory condition of the colon characterized by chronic watery diarrhea, generally with endoscopically normal or nonspecific findings, and can be diagnosed by histopathological examination of colon mucosal biopsies. Some patients experience severe symptoms that do not respond to conventional medical treatment. A glucagon-like peptide-2 (GLP-2) analog, teduglutide, is used in patients with short bowel syndrome (SBS) dependent on parenteral support. In this case report, we describe a patient with microscopic colitis who demonstrated significant symptom improvement following teduglutide treatment.

Microscopic Colitis: Pathogenesis and Diagnosis

Microscopic colitis is a type of inflammatory bowel disease and is classified as either collagenous colitis or lymphocytic colitis. The typical presentation is chronic watery diarrhea. The disease occurs more frequently in women aged 60-65 years and is increasing in incidence. The pathophysiology of microscopic colitis remains poorly understood and has not been well-described with possible several pathogeneses. To date, the diagnosis of microscopic colitis depends on histological tissue obtained during colonoscopy. Other non-invasive biomarkers, such as inflammatory markers and fecal biomarkers, have been studied in microscopic colitis, but the results remains inconclusive. The approach to chronic diarrhea is important and being able to differentiate chronic diarrhea in patients with microscopic colitis from other diseases, such as inflammatory bowel disease, functional diarrhea, and malignancy, by using non-invasive biomarkers would facilitate patient management. The management of microscopic colitis should be based on each individual's underlying pathogenesis and involves budesonide, bile acid sequestrants, or immunosuppressive drugs in refractory cases. Cigarette smoking and certain medications, especially proton pump inhibitors, should be eliminated, when possible, after the diagnosis is made.

What do we know today about drug-induced microscopic colitis? A case of lymphocytic colitis on olmesartan

Microscopic colitis is part of the differential diagnosis of chronic watery diarrhea. Colonoscopy discloses a normal looking mucosa, therefore its diagnosis is based on histology of colonic biopsies. Two main phenotypes are distinguished: collagenous colitis and lymphocytic colitis. A third entity, incomplete microscopic colitis or unspecified microscopic colitis has been reported in the literature. It affects preferentially women over 60 years of age and its association with certain drugs is increasingly established. In case of suspected drug-induced microscopic colitis, identification of the responsible drug is a key to management. After discontinuation of the suspected drug, the gold standard of treatment is budesonide both for induction and for maintenance in case of clinical relapse, as is often the case after discontinuation. Therapy with immunomodulators, biologics, or surgery is reserved for refractory forms of microscopic colitis after multidisciplinary consultation. Through the clinical case of colitis on olmesartan, we will review the latest recommendations on drug-induced microscopic colitis.

Regional differences in the incidence of lymphocytic and collagenous colitis over time

BACKGROUND

In microscopic colitis (MC), the incidence has increased over the last decades. The aim of the present study was to determine the incidence of lymphocytic (LC) and collagenous colitis (CC) in the county Skåne (Scania), southern Sweden, during the period 2010-20 with focus both on the temporal and spatial variations.

METHODS

The MC diagnosis was retrieved from the biopsy registries at the Departments of Pathology. Established diagnostic criteria (increased lymphocyte count, inflammation in lamina propria and in CC a collagen band) were used for diagnosis. Age, gender, date for diagnosis and municipality of residence were retrieved for all patients.

RESULTS

In total 1985 patients could be identified with a mean age of 62.9 years (SD 15.7) whereof 1415 were women. The incidence for CC was stable with a total age-standardized rate (ASR) per 100 000 person-years of 6.34, (range 4.6-8.1). In LC the ASR was 7.90 (range 1.7-15.2) but increased markedly 2015-20 reaching 15.2 in 2019. Also, the northwest part of the region showed significantly higher ASR:s of LC during the last part of the decade in comparation to the whole region.

CONCLUSIONS

The incidence of CC was stable during the period while LC differed substantially in a way that indicates that it most probably must be two different disease entities. In LC, in view of the marked and rapid increase, although no definitive explanation could be found, causative environmental factors could be contemplated, why further studies are indicated.

Microscopic colitis is a risk factor for low bone density: a systematic review and meta-analysis

Background

Microscopic colitis (MC) is a chronic inflammatory disease of the large bowel characterized by watery diarrhea, substantially decreasing the patient's quality of life. Scarce data suggest that MC is associated with low bone density (LBD).

Objectives

We aimed to assess whether MC is a risk factor for LBD and the proportion of patients with MC having LBD.

Design

A systematic review and meta-analysis of studies reporting bone density measurements in MC patients.

Data Sources and Methods

We systematically searched five databases from inception to October 16, 2021 (Pubmed, Embase, Cochrane, Scopus, and Web of Science). We used the random-effect model to calculate pooled odds ratios (ORs) and pooled event rates with 95% confidence intervals (CIs). To ascertain the quality of evidence of our outcomes, we followed the recommendations of the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) Working Group.

Results

The systematic search yielded a total of 3046 articles. Four articles were eligible for quantitative synthesis. All of them used age- and sex-matched controls to evaluate LBD occurrence among patients with MC. The odds of having LBD were twofold increased (OR = 2.13, CI: 1.42-3.20) in the presence of MC, the odds of osteopenia occurrence were 2.4 (OR = 2.45, CI: 1.11-5.41), and of osteoporosis 1.4 (OR = 1.42, CI: 0.65-3.12). The proportion of LBD was 0.68 (CI: 0.56-0.78), osteopenia was 0.51 (CI: 0.43-0.58), and osteoporosis was 0.11 (CI: 0.07-0.16) among the MC population. Our findings' certainty of the evidence was very low following the GRADEPro guideline.

Conclusion

Our data demonstrate that MC is associated with a twofold risk for LBD. Based on our findings, we suggest screening patients for bone mineral density upon diagnosis of MC. Further prospective studies with higher patient numbers and longer follow-up periods on this topic are needed.

Registration

Our protocol was prospectively registered with PROSPERO (CRD42021283392).

Fecal calprotectin level in microscopic colitis: a systematic review and meta-analysis

Background

There are no specific biomarkers for microscopic colitis (MC), and the diagnosis depends on histopathological tissue obtained during colonoscopy. Studies on the role of fecal calprotectin (FCP) in MC are limited. A literature search of PubMed, Embase, and Scopus was conducted from each database's inception through September 2022.

Methods

A DerSimonian-Liard random-effects meta-analysis was performed to examine the standardized mean difference (SMD) in FCP levels between patients with MC and control patients with chronic diarrhea.

Results

Six studies with 96 active MC patients and 200 controls were included in the meta-analysis. Random effects meta-analysis revealed that FCP was significantly and moderately elevated in patients with MC compared to the control group (SMD = 0.6 [95% CI 0.3, 1.0], P = 0.001). Imputing one effect size confirmed the observation that FCP is significantly higher in patients with MC than control subjects with chronic diarrhea (SMD = 0.5 [95% CI 0.2, 0.9], P = 0.004). Study heterogeneity between the SMDs was not significant (I2 = 41%, P = 0.1).

Conclusion

These results indicate that FCP levels in patients with chronic diarrhea can help identify patients with MC. More studies with serial measurements of FCP would provide a better understanding of its utility in MC.

Impact of Anti-CD20 therapies on the immune homeostasis of gastrointestinal mucosa and their relationship with de novo intestinal bowel disease in multiple sclerosis: a review

Multiple sclerosis (MS) and inflammatory bowel disease (IBD) are autoimmune disorders characterized by inflammatory episodes affecting the brain and the gastrointestinal (GI) tract, respectively. The frequent association between MS and IBD suggests that both conditions may share common pathogenic mechanisms. However, different responses to biological therapies indicate differences in immune mechanisms of inflammation. Anti-CD20 therapies are high efficacy treatments increasingly used to control inflammatory bursts in MS, but they may alter GI homeostasis and promote the development of bowel inflammation in susceptible individuals. This review analyzes the mechanistic association between immunity in MS and IBD, the effect of anti-CD20 therapies on the gut microenvironment, and provides recommendations for early detection and management of GI toxicities in the context of B-cell depletion in MS patients.

What is the incidence of celiac disease in patients with microscopic colitis? Why are these two diseases related?

Introduction

Although there are studies in the literature showing that celiac disease (CD) is more common in patients with microscopic colitis (MC), there are publications to the contrary. The pathophysiologies of both diseases are different from each other.

Aim

To investigate the frequency of CD in MC patients, the different features of these 2 diseases, and the relationship between them.

Material and methods

In our prospective and cross-sectional analytical study, the presence of CD was investigated in 90 patients diagnosed with MC by colonoscopy and biopsy due to chronic diarrhoea between September 2011 and December 2021.

Results

We detected MC in 102 (9.3%) of 1096 patients investigated for chronic diarrhoea. We detected CD in 1 (1.1%) of 90 patients with MC who participated in the study. Only 10% of the patients were positive for AGA IgA, 3.3% for EMA IgA, and 2.2% for Anti-TG2 IgA. There was no difference in autoantibody titre in treatment-responsive and treatment-resistant MC patients. HLA DQ2 was positive in 32.2% (n = 29) of the MC patients, and HLA DQ8 was found in 5.5% (n = 5). Intraepithelial lymphocyte increase was remarkable in the duodenal biopsies of MC patients who did not respond to treatment (40% vs. 11.4%; p = 0.007).

Conclusions

We did not reach the conclusion that CD is more common in MC patients. An increase in IEL may also occur in the small intestine in patients with MC who do not respond to treatment.

Microbiome Composition in Microscopic Colitis: A Systematic Review

Believed to be a rare cause of chronic diarrhoea, microscopic colitis (MC) is a condition with rising incidence. Many prevalent risk factors and the unknown pathogenesis of MC rationalise the need for studies on microbiota composition. PubMed, Scopus, Web of Science and Embase were searched. Eight case-control studies were included. The risk of bias was assessed with the Newcastle-Ottawa Scale. Clinical details on the study population and MC were poor. The most consistent result among the studies was a decreased Akkermansia genus in faecal samples. Other results were inconsistent due to the different taxonomic levels of the outcomes. Possible changes in different taxa were observed in patients who suffered from MC compared to healthy controls. The alpha diversity compared between MC and the diarrhoea control may suggest potential similarities. The beta diversity in MC compared to healthy and diarrhoeal populations showed no significant outcomes. The microbiome composition in MC possibly differed from the healthy control, but no agreement regarding taxa was made. It might be relevant to focus on possible factors influencing the microbiome composition and its relationship with other diarrhoeal diseases.

Tofacitinib for celiac disease and microscopic colitis: killing two birds with one stone

Microscopic colitis is a chronic inflammatory condition of the colon. Firstline treatment consists of budesonide, with the consideration of biological agents in refractory cases. Celiac disease is a chronic immune mediated and gluten-induced enteropathy, with treatment consisting of a gluten-free diet. There is an association between microscopic colitis and instead of xand celiac disease, especially in refractory cases they can coincide. In this manuscript, we report for the first time the efficacy of tofacitinib, a pan Janus kinase inhibitor, in the treatment of concomitant microscopic colitis and celiac disease, resulting in persistent clinical and histological remission.

Celiac disease and risk of microscopic colitis: A nationwide population-based matched cohort study

BACKGROUND

An association has been reported between celiac disease (CD) and microscopic colitis (MC). However, large, population-based cohort studies are rare.

OBJECTIVE

To systematically examine the association between CD and MC in a large, nationwide cohort.

METHODS

We conducted a nationwide population-based matched cohort study in Sweden of 45,138 patients with biopsy-verified CD (diagnosed in 1990-2016), 223,149 reference individuals, and 51,449 siblings of CD patients. Data on CD and MC were obtained from all (n = 28) pathology departments in Sweden. Adjusted hazard ratios (aHRs) were calculated using Cox regression.

RESULTS

During follow-up, 452 CD patients and 197 reference individuals received an MC diagnosis (86.1 vs. 7.5 per 100,000 person-years). This difference corresponded to an aHR of 11.6 (95% confidence interval [CI] = 9.8-13.8) or eight extra MC cases in 1000 CD patients followed up for 10 years. Although the risk of MC was highest during the first year of follow-up (aHR 35.2; 95% CI = 20.1-61.6), it remained elevated even after 10 years (aHR 8.1; 95% CI = 6.0-10.9). Examining MC subtypes lymphocytic colitis (LC) and collagenous colitis (CC) separately, the aHR was 12.4 (95% CI = 10.0-15.3) for LC and 10.2 (95% CI = 7.7-13.6) for CC. MC was also more common before CD (adjusted odds ratio [aOR] = 52.7; 95% CI = 31.4-88.4). Compared to siblings, risk estimates decreased but remained elevated (CD and later MC: HR = 6.2; CD and earlier MC: aOR = 7.9).

CONCLUSION

Our study demonstrated a very strong association of MC with CD with an increased risk of future and previous MC in CD patients. The magnitude of the associations underscores the need to consider the concomitance of these diagnoses in cases in which gastrointestinal symptoms persist or recur despite a gluten-free diet or conventional MC treatment. The comparatively lower risk estimates in sibling comparisons suggest that shared genetic and early environmental factors may contribute to the association between CD and MC.

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.

Diagnostic yield of colonoscopy for organic disease in irritable bowel syndrome and its risk factors: A meta-analysis

BACKGROUND

Colonoscopy is commonly performed in patients with irritable bowel syndrome (IBS) to rule out organic disease. We performed a meta-analysis to assess the prevalence of organic disease detected at colonoscopy in IBS and its potential risk factors.

METHODS

Medline, Embase, and Web of Science were searched through January 2022. Observational studies that reported diagnostic yield of colonoscopy for organic disease including colorectal cancer (CRC), inflammatory bowel disease (IBD), or microscopic colitis (MC) in adult IBS patients were eligible. Pooled prevalence and risk difference (RD) with 95% confidence intervals (CIs) were calculated.

RESULTS

Of 2490 citations identified, 12 studies were eligible containing 28,630 patients with IBS undergoing colonoscopy. Pooled prevalence of CRC, IBD, and MC in IBS was 0.78%, 4.48%, and 2.35%, respectively. No difference in the yield for CRC, IBD, and MC was seen between IBS and non-IBS patients. CRC was rare in IBS patients without alarm symptoms or younger than 40 years (<0.1%). Pooled Prevalence of CRC (2.47% vs. 0.11%; RD 2.57%, 95% CI 0.37%-4.78%) and IBD (8.86% vs. 4.25%; RD 10.75%, 95% CI 4.81%-16.68%) was significantly higher in IBS patients with alarm symptoms compared with those without. IBD and MC were more likely to be detected at colonoscopy in IBS-D compared with IBS-C. The prevalence of CRC and MC was higher in IBS patients with older age than younger age.

CONCLUSION

We provide the first pooled estimate of yield of colonoscopy in IBS and its risk factors, which may be used to inform clinical decision and support guidelines.

Medically Refractory Lymphocytic Colitis Successfully Treated With Upadacitinib

Lymphocytic colitis is a microscopic colitis characterized endoscopically by nearly normal-appearing colonic mucosa and histology demonstrating intraepithelial lymphocytosis. Microscopic colitis that is refractory to conventional therapies, including budesonide, is rare but challenging and with scarce evidence. Upadacitinib is a novel Janus kinase 1 selective inhibitor approved by the US Food and Drug Administration for atopic dermatitis, rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, and moderately to severely active ulcerative colitis. We present the first case of lymphocytic colitis refractory to conventional and immunosuppressive therapies, which responded promptly to upadacitinib.

The natural history of histological changes in microscopic colitis

Background

Microscopic colitis (MC) causes chronic diarrhea. It has two histologic subtypes: lymphocytic colitis (LC) and collagenous colitis (CC). Little is known about the natural progression of disease with time and with treatment.

Objectives

We aimed to assess histological changes over time.

Design

We designed a retrospective study including adults diagnosed with MC from January 1992 to January 2020 at Mayo Clinic.

Methods

Pathology reports were reviewed until 31 October 2020. Histological assessments at least 8 weeks apart were considered as adequate follow-up. Histological change from one subtype to the other and resolution were tracked with univariate and multivariable Cox proportional hazards models.

Results

Overall, 416 patients with a median age at diagnosis of 63.9 years with >1 histopathological assessment were identified. Histology at initial diagnosis was CC in 218 (52.4%) patients and LC in 198 (47.6%). No medications were associated with a histological change. However, histological resolution was more likely with the use of aspirin [hazard ratio (HR): 2.10, 95% confidence interval (CI): 1.34-3.31, p = 0.001) and proton-pump inhibitors (PPIs; HR: 2.01, 95% CI: 1.34-3.02, p = 0.001). Histological resolution was more likely with budesonide treatment (HR: 1.86, 95% CI: 1.16-3.00, p = 0.010) and less likely with mesalamine (HR: 0.40, 95% CI: 0.19-0.83, p = 0.014), compared to medications such as prednisone, loperamide, and bismuth. Patients with CC were less likely to change their histology compared to patients with LC (HR: 0.24, 95% CI: 0.14-0.42, p < 0.001). There was no difference in histological resolution between the two subtypes (HR: 0.70, 95% CI: 0.47-1.05, p = 0.084).

Conclusion

Patients with LC have a higher chance of changing their histology as compared to CC. However, histological resolution was associated with the use of PPIs and aspirin, and treatment with budesonide.

Autoimmune and immune-mediated inflammatory diseases after exposure to acid-suppressive medication: A systematic review and meta-analysis

BACKGROUND

Pharmacovigilance risk signals have proposed a relationship between the use of acid-suppressive medications and the development of certain autoimmune and immune-mediated inflammatory diseases.

OBJECTIVE

A systematic review and a meta-analysis was performed.

METHODS

We reviewed MEDLINE (Ovid) and Scopus for comparative observational studies between these diseases and previous exposure to proton-pump inhibitors (PPI), H2-receptor antagonists (H2RA), and antacids. The protocol was registered on the PROSPERO database (CRD42020192715).

RESULTS

From 3,191 citations, 25 articles were eligible and covered 16 diseases. Microscopic colitis (MC) was studied the most (7 studies). In a random-effects meta-analysis, there was low certainty evidence (GRADE approach) of a non-significant relationship between exposure to any PPIs and MC (meta-OR 3.28, 95% CI 0.98-11.0, I2 98.2%, six studies, 4,436 PPI-exposed MC patients). Moderate certainty evidence pointed towards large odds of collagenous colitis after exposure to lansoprazole (meta-OR 14.5, 95% CI 9.37-22.3, I2 10.2%, three studies, 1,725 lansoprazole-exposed patients). After PPI exposure, the risk of rheumatoid arthritis was slightly increased based on low certainty evidence from two cohort studies totaling 475 diagnoses (meta-RR 1.62, 95% CI 1.12-2.34, I2 34.5%).

CONCLUSIONS

In patients with MC, it would be reasonable to carefully review the indication of PPI, especially in CC patients using lansoprazole.

Are Drugs Associated with Microscopic Colitis? A Systematic Review and Meta-Analysis

There is growing evidence of the association of Microscopic Colitis (MC) with the use of specific medications such as proton pump inhibitors (PPIs), Selective serotonin reuptake inhibitors (SSRIs), Non-Steroidal anti-inflammatory drugs (NSAIDs), Statins and H2-receptor antagonists (H2RA). In our study, we calculated the pooled odds of MC in patients using these drugs. We performed a detailed search of major databases, including PubMed/Medline, Scopus, web of science, and Embase, to include the studies in which odds of MC were reported after using above mentioned drugs. A random-effects model was used to pool the estimates. Thirteen studies were included in our analysis consisting of 304,482 patients (34,194 cases and 270,018 controls). In eight studies, the control group consisted of a random population selected based on age, gender and same birth year, whereas 3 studies recruited patients who presented with diarrhea and underwent colonoscopy and biopsy to rule out MC. Two studies reported odds of MC for both diarrhea and random control groups. Patients taking PPIs were more likely to develop MC, AOR 2.65 (95% CI 1.81-3.50, I² 98.13%). Similarly, higher odds of association were found in patients taking SSRIs (OR 2.12, 95% CI 1.27-2.96, I² 96.46%), NSAIDs (OR 2.02, 95% CI 1.33-2.70, I² 92.70%) and Statins (OR 1.74, 95% CI 1.19-2.30, I² 96.36%). No difference in odds of developing MC was seen in patients using H2RA compared to the control group (OR 2.70, 95% CI 0.32-5.08, I² 98.67%). We performed a subgroup analysis based on the control group and found higher odds of MC in patients on PPIs compared to the random control group (OR 4.55, 95% CI 2.90-6.19, I² 98.13%). Similarly, higher odds of MC were noted for SSRI (OR 3.23, 95% CI 1.54-4.92, I² 98.31%), NSAIDs (OR 3.27, 95% CI 2.06-4.48, I² 95.38%), and Statins (OR 2.23, 95% CI 1.41-3.06, I² 98.11%) compared to the random control group. Contrary lower odds of MC were seen in the PPI and H2RA group compared to the diarrhea control group (OR 0.68, 95% CI 0.48-0.88, I² 7.26%), (OR 0.46, 95% CI 0.14-0.78, I² 0%) respectively. We found no difference in odds of MC in patients on SSRIs (OR 0.96, 95% CI 0.49-1.42, I² 37.89%), NSAIDs (OR 1.13, 95% CI 0.49-1.76, I² 59.37%) Statins (OR 0.91, 95% 0.66-1.17, I² 0%) and H2RA (OR 3.48, 95% CI -0.41-7.36, I² 98.89%) compared to the diarrhea control group. We also analyzed the association use of PPIs and NSAIDs with the development of collagenous colitis (CC) and lymphocytic colitis. Only the use of NSAIDs was associated with increased odds of developing collagenous colitis (OR 1.61, 95% CI 1.50-1.72, I² 0%). No increased odds of CC and LC were seen in PPI users. PPIs, NSAIDs, SSRIs, and Statins are associated with an increased risk of MC compared to the random control group. On the contrary, the use of PPIs, NSAIDs, SSRIs, and Statins is not associated with an increased risk of MC when compared to the diarrhea control group.

Biologic Therapy for Budesonide-refractory, -dependent or -intolerant Microscopic Colitis: a Multicentre Cohort Study from the GETAID

BACKGROUND

Budesonide remains the backbone therapy for microscopic colitis [MC]; however, relapses are frequent, and some patients are intolerant or dependent. Anti-TNF therapy is increasingly used to treat these patients, but available evidence is still limited. The aim of this study was to evaluate the effectiveness and safety of anti-TNF therapy in MC patients failing budesonide.

METHODS

In a multicentre retrospective cohort study, budesonide-refractory, -dependent, or -intolerant MC patients treated with anti-TNF agents were included. Clinical remission was defined as fewer than three bowel movements per day, and clinical response was defined as an improvement in stool frequency of at least 50%.

RESULTS

Fourteen patients were included. Median age was 58.5 years, median disease duration was 25 months, and median follow-up was 29.5 months. Seven patients were treated with infliximab [IFX], and seven with adalimumab. Clinical remission without steroids at 12 weeks was reached in 5/14 [35.7%] patients; all of these received IFX. Clinical response at 12 and 52 weeks, was obtained in 9/14 [64.3%] and 7/14 [50%] patients, respectively. Five patients switched to another anti-TNF agent. When considering both first- and second-line anti-TNF therapies, 7 [50%] patients were in clinical remission at Week 52. Mild to moderate adverse events were reported in six ptients. Two patients were treated with vedolizumab, of whom one had clinical response; one patient treated with ustekinumab had no response.

CONCLUSIONS

This is the first multicentre cohort study showing that half of patients treated with anti-TNF therapy for MC achieved clinical remission in case of budesonide failure.

Microscopic colitis in Northern Ireland: an updated clinicopathological audit and assessment of compliance with European guidelines

AIM

We previously reported the first population-based study of the epidemiology of microscopic colitis in Northern Ireland. The aim of the current study is to provide updated data on incidence, diagnostic methods and clinicopathological associations, following dissemination of the previous report. A further aim was to compare the findings against relevant recommendations from the 2020 European guidelines.

METHOD

Study cases were identified via the Belfast Health and Social Care Trust pathology laboratory system for new cases of collagenous colitis or lymphocytic colitis diagnosed from 2017 to 2020 inclusive. Demographic and clinical information was collated from electronic healthcare records.

RESULTS

Two hundred and seventeen new diagnoses of microscopic colitis were made between 2017 and 2020, comprising 89 (41%) collagenous colitis and 128 (59%) lymphocytic colitis. The overall incidence of microscopic colitis, expressed per 100,000 adult population, ranged from 7.6 to 11.5 (5.9 to 9.0 per 100,000 total population). The 2019 peak of 11.5 cases per 100,000 adult population represents a 71.6% increase in incidence compared with the mean incidence of 6.7 per 100,000 adult population from previous data for 2008-2016. There has also been a significant increase in number of cases diagnosed on separate sampling from the right and left colon (85% in 2019-2020 compared with 30% in 2008-2016; p < 0.001). Overall compliance with coeliac serology testing has improved, with 89% tested in 2017-2018 compared with 75% in 2008-2016.

CONCLUSION

Clinicopathological communication has contributed to an increased incidence of microscopic colitis in Northern Ireland through better endoscopic diagnostic sampling and pathology coding practices. Coeliac serology testing has also improved, although continued clinical awareness is required of the need for coeliac serology testing in all patients diagnosed with microscopic colitis.

Increased incidence of late-onset inflammatory bowel disease and microscopic colitis after a Cryptosporidium hominis outbreak

OBJECTIVES

In 2010, 27,000 inhabitants (45% of the population) of Östersund, Sweden, contracted clinical cryptosporidiosis after drinking water contaminated with Cryptosporidium hominis. After the outbreak, local physicians perceived that the incidence of inflammatory bowel disease (IBD), including ulcerative colitis (UC), Crohn's disease (CD), and IBD-unclassified, and microscopic colitis (MC) increased. This study assessed whether this perception was correct.

MATERIALS AND METHODS

This observational study included adult patients (≥18 years old) from the local health care region who were diagnosed with pathology-confirmed IBD or MC during 2006-2019. We collected and validated the diagnosis, date of diagnosis, age at diagnosis, and sex from the Swedish quality register SWIBREG and electronic patient records. Population data were collected from Statistics Sweden. The incidences for 2006-2010 (pre-outbreak) and 2011-2019 (post-outbreak) were evaluated by negative binomial regression analysis and presented as incidence rate ratios (IRRs). Data were analyzed for IBD, for UC and CD separately, and MC.

RESULTS

During the study period, we identified 410 patients with new onset IBD and 155 new cases of MC. Overall, we found a trend toward an increased incidence of IBD post-outbreak (IRR 1.39, confidence interval (CI) 0.99-1.94). In individuals ≥40 years old, the post-outbreak incidence significantly increased for IBD (IRR 1.69, CI 1.13-2.51) and CD (IRR 2.23, CI 1.08-4.62). Post-outbreak incidence of MC increased 6-fold in all age groups (IRR 6.43, CI 2.78-14.87).

CONCLUSIONS

The incidence of late-onset IBD and MC increased after the Cryptosporidium outbreak. Cryptosporidiosis may be an environmental risk factor for IBD and MC.

Is mastocytic colitis a specific clinical-pathological entity?

The number of intestinal mast cells (MC) is increased in several types of colitis, but the mucosa of patients with chronic non-bloody diarrhea has not been studied. The current study sought to determine the relationship between MC counts and degranulation and the severity of symptoms in patients with chronic loose stools. Following a negative laboratory workup for the most common causes of chronic diarrhea, patients with chronic non-bloody loose stools were included in the study. Patients with macroscopic evidence of inflammation or organic disease were excluded after endoscopy with biopsies. Biopsies from the 179 patients in the study were stained with hematoxylin and eosin and anti-CD117 c-kit antibodies. Immunohistochemistry was used to assess the degree of MC degranulation. Out of the 179 patients, 128 had normal histologic findings suggestive of irritable bowel syndrome and were used as controls. Twenty-four presented with abnormally high MC counts (≥40 MC x HPF), 23 with ≥20 intraepithelial lymphocytes x HPF suggesting lymphocytic colitis, and 4 had both (≥40 MC and ≥20 intraepithelial lymphocytes x HPF). In the patients with high MC counts, figures were significantly higher in the right colon versus the left colon (p=0.016), but degranulation did not differ in the right versus the left colon (p=0.125). No age or sex-related difference was observed (p=0.527 and p=0.859 respectively). The prevalence of abdominal pain and bloating did not differ in the three groups (p=0.959 and p=0.140, respectively). Patients with lymphocytic colitis (p=0.008) and those with high MC counts (p=0.025) had significantly higher evacuation rates compared to controls. There was no difference between these two groups (p=0.831). Mast cell degranulation was not associated with the number of evacuations, abdominal pain, or bloating (p=0.51; p=0.41; p=0.42, respectively). The finding that a significantly higher number of evacuations was linked to increased MC in the colonic mucosa of a subset of patients with otherwise normal laboratory and endoscopic findings suggests that "mastocytic colitis" may be a new clinical-pathological entity responsible for chronic non-bloody diarrhea. Prospective studies with a larger number of patients, as well as endoscopic and histological follow-up, are needed to confirm this hypothesis.

Microscopic Colitis Is Associated With a Reduced Risk of Colorectal Adenoma and Cancer: A Meta-Analysis

BACKGROUND

The study sought to conduct a systematic review and meta-analysis of the risk of colorectal adenoma or cancer in patients with microscopic colitis (MC).

METHODS

A comprehensive literature search of PubMed and EMBASE databases was performed. Pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated to examine the effect of MC on the risk of colorectal adenoma or cancer.

RESULTS

Twelve studies reporting the outcomes of 50 795 patients with MC were eligible for this meta-analysis. MC was negatively associated with the risk of colorectal adenoma compared with participants without MC (RR, 0.44; 95% CI, 0.33-0.58; P < .001; I2 = 87.3%). Also, the rate of colorectal cancer was lower in the patients with MC compared with the general population (RR, 0.62; 95% CI, 0.43-0.89; P = .01; I2 = 91.6%). In addition, sensitivity and subgroup analyses indicated that the results were robust.

CONCLUSIONS

The present systematic review indicated that patients with MC may be associated with a lower risk of colorectal adenoma or cancer. The clinical data support the current professional society guideline. A surveillance colonoscopy program is not recommended as standard for patients with MC.

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.

Collagenous Colitis Possibly Associated with Dipeptidyl Peptidase-4 Inhibitor

A 60-year-old man with type 2 diabetes mellitus treated with a dipeptidyl peptidase-4 (DPP-4) inhibitor was referred to our hospital because of his refractory watery diarrhea. Ileocolonoscopy revealed increased capillary growth, fine granular mucosa, and longitudinal mucosal tears mainly in the left side of the colon. A bioptic examination revealed thickened subepithelial collagen bands, thus confirming the diagnosis of collagenous colitis. Systemic steroid therapy was initiated, but his symptoms recurred when tapering the steroid. However, withdrawal of the DPP-4 inhibitor was successful even after the cessation of steroid therapy. We therefore considered his collagenous colitis to have been caused by the DPP-4 inhibitor.

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.

Vedolizumab blocks α4β7 integrin-mediated T cell adhesion to MAdCAM-1 in microscopic colitis

BACKGROUND

In Crohn's disease and ulcerative colitis, the anti-α4β7 integrin antibody vedolizumab has demonstrated efficacy in phase III trials and has been successfully used under real-world conditions. Occasionally, it has also been used in other forms of inflammatory bowel disease (IBD) such as microscopic colitis (MC). However, the mechanisms of vedolizumab in MC have not been studied to date. Therefore, we aimed to investigate the expression and functional role of gut-homing integrins and in particular α4β7 integrin in a cohort study in MC.

METHODS

We studied the expression of gut homing integrins on T cells from patients with MC and healthy controls by flow cytometry. To investigate the function of α4β7 integrin in MC and the potential of vedolizumab to block it, we used dynamic adhesion assays and transmigrations assays. Moreover, we describe two clinical cases of MC patients treated with vedolizumab.

RESULTS

A specific profile of gut homing markers can be found on T cells from patients with MC. α4β7 integrin functionally leads to firm adhesion to MAdCAM-1 and supports transmigration. Vedolizumab is able to block both processes. In two cases of MC, we observed reduced clinical symptoms and histologic improvement upon therapy with vedolizumab.

CONCLUSION

Our data suggest that α4β7 mediates gut homing of T cells also in MC and that, on single cell level, vedolizumab blocks the function of α4β7 in MC. Thus, we provide mechanistic evidence supporting vedolizumab as promising therapeutic option for MC.

Abnormal findings on abdominopelvic cross-sectional imaging in patients with microscopic colitis: a retrospective, multicenter study

OBJECTIVES

Patients with microscopic colitis may have subtle macroscopic findings on colonoscopy such as erythema, edema, or altered vascular pattern; however, radiographic abnormalities on cross-sectional imaging have not been investigated. We aimed at identifying the abdominopelvic radiographic abnormalities in patients with microscopic colitis, as well as possible correlation with endoscopic findings and the need for extended duration of treatment.

MATERIALS AND METHODS

This was a retrospective study of patients with biopsy-proven microscopic colitis at two tertiary centers between 1 January 2010 and 30 April 2020. Patients underwent computed tomography scan or magnetic resonance imaging within 30 days of a diagnostic flexible sigmoidoscopy or colonoscopy. Patients with colon ischemia and other causes of colitis were excluded. Radiographic abnormalities from imaging reports included bowel wall thickening, mucosal hyperenhancement and mesenteric fat stranding. Univariate and multivariable logistic regression models were used to identify predictors of radiographic abnormalities.

RESULTS

498 patients with microscopic colitis underwent abdominopelvic cross-sectional imaging within 30 days of flexible sigmoidoscopy/colonoscopy. Lymphocytic colitis was diagnosed in 54.6% of patients, and collagenous colitis in 45.4%. Endoscopic and radiographic abnormalities were identified in 16.1% and 12.4% of patients, respectively. Radiographic abnormalities were associated with the need for budesonide therapy (p = .029) and budesonide therapy long-term (p = .0028). Budesonide therapy long-term (p = .047) was associated with radiographic abnormalities in multivariate analysis.

CONCLUSIONS

Radiographic abnormalities may be present on abdominopelvic cross-sectional imaging in a minority of patients with biopsy-proven microscopic colitis, suggesting cross-sectional imaging has low clinical value in the evaluation and treatment of this disease.

Patients With Microscopic Colitis Have Altered Levels of Inhibitory and Stimulatory Biomarkers in Colon Biopsies and Sera Compared to Non-inflamed Controls

Introduction: Microscopic colitis (MC) is an inflammatory bowel condition with two subtypes, lymphocytic colitis (LC) and collagenous colitis (CC). Unlike patients with ulcerative colitis (UC) and non-inflamed individuals, MC patients have reduced risk of developing colorectal cancer, possibly due to increased immune surveillance in MC patients.

Aim: To examine differences in levels of immunomodulatory molecules, including those involved in immune checkpoint mechanisms, in sera from patients with MC and in colonic biopsies from patients with MC and UC compared with controls.

Methods: Using Luminex, 23 analytes (4-1BB, 4-1BBL, APRIL, BAFF, BTLA, CD27, CD28, CD80, CTLA-4, E-cadherin, Galectin-3, GITR, HVEM, IDO, IL-2Rα, LAG-3, MICA, MICB, PD-1, PD-L1, PD-L2, sCD40L and TIM-3) were studied in serum from patients with active MC (n = 35) and controls (n = 23), and in colonic biopsies from patients with active LC (n = 9), active CC (n = 16) and MC in histological remission (LC n = 6, CC n = 6), active UC (n = 15) and UC in remission (n = 12) and controls (n = 58).

Results: In serum, IDO, PD-1, TIM-3, 4-1BB, CD27, and CD80 were decreased whereas 4-1BBL and IL-2Rα were increased in MC patients compared with controls. In contrast, in biopsies, levels of PD-L2 and 4-1BB were increased in MC and UC patients with active disease. Furthermore, in biopsies from CC and UC but not LC patients with active disease, CTLA-4, PD-1, APRIL, BAFF, and IL-2Rα were increased compared with controls. PD-L1 was increased in CC but not UC or LC patients. CD27 and TIM-3 were decreased in biopsies from MC patients in comparison to controls whereas levels of MICB were decreased in patients with active UC compared with controls.

Conclusions: Compared with non-inflamed controls, levels of soluble and membrane-bound immunomodulatory molecules were systemically and locally altered in MC and UC patients, with most analytes being decreased in serum but enhanced in colonic biopsies. These findings contribute to knowledge about checkpoint molecules and their role as biomarkers in MC and may also contribute to knowledge about possible mechanisms behind the seemingly protective effects of MC against colorectal cancer.

Macroscopic to Microscopic - A Case of Crohn's Disease Progressing to Collagenous Colitis

The association between microscopic colitis (MC) and inflammatory bowel disease (IBD) is uncertain and infrequently reported. Rare cases in the literature consist of simultaneous MC and IBD, or progression of one condition to the other. We present a unique case of clinically and endoscopically diagnosed and successfully treated IBD that revealed MC on histology months later due to reappearance of diarrhea. Common pathophysiologic mechanisms, such as tumor necrosis factor α and T helper type 1 cells, may explain the MC and IBD relationship. During endoscopy, a prompt biopsy should be taken if suspicious for MC, thus decreasing the duration of patient's symptoms and saving healthcare costs.

Controversials of Microscopic Colitis

Microscopic colitis (MC) has become a disease with increased awareness due to the availability of new data about the pathogenesis, diagnosis and therapy of this disease. The incidence of MC is increasing, reaching the incidence of the inflammatory bowel disease (IBD) in some populations. However, some aspects of MC are still controversial. It is unknown whether the changes of microbiome play a role in the pathogenesis and what is in the background of the different subtypes of disease that can transform into each other. Is there a connection between MC and IBD or why the histological changes do not follow the clinical activity? We do not know what the etiology of the incomplete MC is, and what its natural course is. The association of MC with celiac disease is well-known- is there a common pathogenesis? The MC treatment is budesonide. Its effectiveness is high, but the relapse rate is high, as well. Why would biologics be effective in these cases when budesonide is not? This mini-review makes an attempt to summarize the data about MC and highlight that there are still unanswered questions in the pathogenesis, diagnosis and therapy of the disease, which can initiate further investigations in the future.

Alcohol Consumption is Associated With An Increased Risk of Microscopic Colitis: Results From 2 Prospective US Cohort Studies

BACKGROUND

No dietary factors have yet been shown to conclusively impact the incidence of microscopic colitis (MC). Here, we sought to examine the relationship between alcohol intake and the risk of MC.

METHODS

We conducted a prospective cohort study of 209,902 participants (age range, 28.5-66.7 years) enrolled in the Nurses' Health Study (NHS) and Nurses' Health Study II (NHSII). Validated data on alcohol consumption were collected at baseline in 1986 in the NHS and 1991 in the NHSII and updated every 4 years. Diagnoses of MC were confirmed via review of histopathology data. We used Cox proportional hazards modeling to estimate adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs).

RESULTS

Through 2016 in the NHS and 2017 in the NHSII, we confirmed 352 incident cases of MC over 4,994,324 person-years. Higher alcohol consumption was associated with an increased risk of MC (Ptrend < .001). Compared to non-users, the aHRs of MC were 1.20 (95% CI, 0.86-1.67) for consumers of 0.1-4.9 g/day of alcohol, 1.90 (95% CI, 1.34-2.71) for consumers of 5-14.9 g/day, and 2.31 (95% CI, 1.54-3.46) for consumers of ≥15 g/day. The associations were consistent across the histologic subtypes of collagenous and lymphocytic colitis (Pheterogeneity = .523). When stratified by alcohol type, the risk according to every 2 servings/week appeared to be strongest with consumption of wine (aHR, 1.08; 95% CI, 1.04-1.12) as compared to beer (aHR, 1.01; 95% CI, 0.91-1.12) or liquor (aHR, 1.00; 95% CI, 0.92-1.09).

CONCLUSIONS

Alcohol consumption was associated with an increased risk of MC. Further studies are needed to determine the mechanism underlying these associations, as well as the impact of reducing alcohol intake in patients with MC.