Long-term prognosis of clinical symptoms and health-related quality of life in microscopic colitis: a case-control study

Association of distinct microbial and metabolic signatures with microscopic colitis

Microscopic colitis (MC) is a chronic inflammatory disease of the large intestine that primarily affects older adults and presents with chronic diarrhea. The etiology is unknown and there are currently no FDA approved medications or biomarkers for treatment or monitoring of the disease. Emerging evidence have implicated the gut microbiome and metabolome disturbances in MC pathogenesis. We conduct a comprehensive analysis of gut microbial and metabolic changes in a cohort of 683 participants, including 131 patients with active MC, 159 with chronic diarrhea, and 393 age- and sex-matched controls without diarrhea. Stool microbiome and metabolome are profiled using whole-genome shotgun metagenomic sequencing and ultra-high performance liquid chromatography-mass spectrometry, respectively. Compared to controls, eight microbial species including pro-inflammatory oral-typical Veillonella dispar and Haemophilus parainfluenzae, and 11 species, including anti-inflammatory Blautia glucerasea and Bacteroides stercoris are enriched and depleted in MC, respectively. Pro-inflammatory metabolites, including lactosylceramides, ceramides, lysophospholipids, and lysoplasmalogens, are enriched in active MC. Multi-omics analyses reveal robust associations between microbial species, metabolic pathways, and metabolites, suggesting concordant disruptions in MC. Here, we show distinct shifts in gut microbiome and metabolome in MC that can inform the development of non-invasive biomarkers and novel therapeutics.

Single-cell transcriptomic characterization of microscopic colitis

Microscopic colitis (MC) is a chronic inflammatory disease of the large intestine and a common cause of chronic diarrhea in older adults. Here, we use single-cell RNA sequencing analysis of colonic mucosal tissue to build a cellular and molecular model for MC. Our results show that in MC, there is a substantial expansion of tissue CD8+ T cells, likely arising from local expansion following T cell receptor engagement. Within the T cell compartment, MC is characterized by a shift in CD8 tissue-resident memory T cells towards a highly cytotoxic and inflammatory phenotype and expansion of CD4+ T regulatory cells. These results provide insight into inflammatory cytokines shaping MC pathogenesis and highlight notable similarities and differences with other immune-mediated intestinal diseases, including a common upregulation of IL26 and an MC-specific upregulation of IL10. These data help identify targets against enteric T cell subsets as an effective strategy for treatment of MC.

Antibiotic Use and Risk of Microscopic Colitis in Older Adults: A Nationwide Self-Controlled Case Series Study

BACKGROUND

Several drugs have been linked to the risk of microscopic colitis (MC), a condition characterised by watery, non-bloody diarrhoea. Antibiotics can induce similar symptoms, but their connection to MC remains unclear.

AIM

To investigate the antibiotic-related risks of MC in adults aged 65 years and older.

METHODS

This was a nationwide, self-controlled case series study including adults aged ≥ 65 years with a new prescription for antibiotics and biopsy-confirmed, incident MC (Sweden, 2007-17). We identified cases from the nationwide histopathology cohort ESPRESSO individually linked to several registers. Using conditional Poisson regression, we estimated incidence rate ratios (IRR) for four risk periods: on treatment, and 1-14, 15-91, and 92-365 days post-treatment, compared with the non-treatment periods in the same individual. We also conducted a negative control outcome analysis to assess whether the association was specific to MC or due to diagnostic workup. E-values were used to assess robustness to unmeasured confounding.

RESULTS

We identified 2393 persons with incident biopsy-confirmed MC (median age at diagnosis 74; 67% women). Compared with the non-treatment periods, the risk of MC in the age-adjusted analysis increased with antibiotic treatment (IRR: 1.44 [95% CI: 1.13-1.84], E-value: 2.24), 1-14 days (IRR: 1.12 [0.83-1.49]), 15-91 days (1.12 [0.97-1.31]) and 92-365 days post-treatment (1.19 [1.07-1.32]). The negative control outcome analysis showed similar risks of biopsy-confirmed normal mucosa after antibiotic use.

CONCLUSION

The observed association between antibiotic use and MC may result from detection bias rather than a causal relationship.

Psychiatric Disorders Among 5,800 Patients With Microscopic Colitis: A Nationwide Population-Based Matched Cohort Study

INTRODUCTION

Microscopic colitis (MC) is an inflammatory condition of the large intestine. Primarily diagnosed in middle-aged and older adults, the incidence of the disease has increased markedly during the past few decades. While MC is associated with a reduced quality of life, large-scale studies on the association with future psychiatric disorders are lacking.

METHODS

We conducted a nationwide matched cohort study in Sweden from 2006 to 2021. Through a nationwide histopathology database (the Epidemiology Strengthened by histoPathology Reports in Sweden study), we identified 5,816 patients with a colorectal biopsy consistent with MC. These patients were matched with 21,509 reference individuals from the general population all of whom with no previous record of psychiatric disorders.

RESULTS

From 2006 to 2021, 519 patients with MC (median age 64.4 years [interquartile range = 49.5-73.3]) and 1,313 reference individuals were diagnosed with psychiatric disorders (9.9 vs 6.5 events per 1,000 person-years), corresponding to 1 extra case of psychiatric disorder in 29 patients with MC over 10 years. After adjustments, the hazard ratio for psychiatric disorders was 1.57 (95% confidence interval = 1.42-1.74). We found significantly elevated estimates up to 10 years after MC diagnosis and a trend toward higher risk with increasing age. Specifically, we observed increased risks for unipolar depression, anxiety disorders, stress-related disorders, substance abuse, and suicide attempts. In sibling-controlled analysis, the adjusted hazard ratio was 1.76 (95% confidence interval = 1.44-2.15).

DISCUSSION

Patients with MC are at increased risk of incident psychiatric disorders compared with the general population.

SARS-CoV-2 as a potential trigger for microscopic colitis in a young adult: A case report

This case highlights the potential role of SARS-CoV-2 in triggering lymphocytic colitis, emphasizing the need for further research and vigilance in identifying potential post-COVID-19 GI complications. We describe a case of a young adult who experienced chronic diarrhea and abdominal pain for 10 months after a SARS-CoV-2 infection. Extensive laboratory and imaging investigations yielded no significant findings. Despite a preliminary diagnosis of irritable bowel syndrome and symptomatic treatment, symptoms persisted. Colonoscopy with biopsies revealed unremarkable colonic mucosa but confirmed moderate lymphocytic infiltration consistent with lymphocytic colitis. Treatment with budesonide achieved complete symptom resolution. The findings underscore the importance for clinicians to consider triggered microscopic colitis in patients presenting with persistent diarrhea following SARS-CoV-2 infection.

Coeliac Disease and Microscopic Colitis: The Largest Study Assessing Prognosis and Risk of Hospital Admission

Microscopic colitis (MC) and coeliac disease (CD) are common associated gastrointestinal conditions. We present the largest study assessing hospitalisation in patients with MC and the effect of a concomitant diagnosis of CD. Data were retrospectively collected between January 2007 and December 2021 from all patients diagnosed with MC and compared to a database of patients with only CD. In total, 892 patients with MC (65% female, median age 65 years (IQR: 54-74 years) were identified, with 6.4% admitted to hospital due to a flare of MC. Patients admitted were older (76 vs. 65 years, p < 0.001) and presented with diarrhoea (87.7%), abdominal pain (26.3%), and acute kidney injury (17.5%). Treatment was given in 75.9% of patients, including intravenous fluids (39.5%), steroids (20.9%), and loperamide (16.3%). Concomitant CD was diagnosed in 3.3% of patients and diagnosed before MC (57 versus 64 years, p < 0.001). Patients with both conditions were diagnosed with CD later than patients with only CD (57 years versus 44 years, p < 0.001). In conclusion, older patients are at a higher risk of hospitalisation due to MC, and this is seen in patients with a concomitant diagnosis of CD too. Patients with MC are diagnosed with CD later than those without.

Microscopic Colitis Secondary to Leflunomide: A Case Report

Microscopic colitis (MC) is characterized by chronic watery diarrhea that requires histological examination for diagnosis. Here, we present a case of a 63-year-old female with rheumatoid arthritis who developed persistent diarrhea following leflunomide initiation. Despite a normal colonoscopy, random colonic biopsies confirmed MC. Discontinuation of leflunomide led to symptom resolution, implicating it as the causative agent. Leflunomide-induced MC is exceedingly rare, with limited documented cases. Understanding its variability in presentation and timely recognition is crucial. This case underscores the importance of thorough medication history assessment and consideration of drug-induced colitis in patients presenting with unexplained diarrhea, facilitating prompt management and resolution.

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.

Follow-Up of Microscopic Colitis Patients and Diarrhea Controls at 1 Year

BACKGROUND AND AIMS

Microscopic colitis (MC) is a common cause of chronic diarrhea; however, the clinical course of this disease is poorly understood. We aimed to investigate how patients diagnosed with MC were treated in routine clinical practice and how their symptoms compared to patients with other causes of chronic diarrhea at one year follow-up.

METHODS

We conducted a case-control study of patients undergoing outpatient colonoscopy to evaluate diarrhea. The study pathologist determined whether patients were classified as MC cases or non-MC controls. One year after colonoscopy, we interviewed cases (n = 74) and controls (n = 162) about their diagnosis, medications for diarrhea, and symptom burden.

RESULTS

At 1-year follow-up after colonoscopy, 10% of MC cases were unaware of the diagnosis, 60% had been prescribed a medication for diarrhea, 40% had fecal urgency, 32% had weight loss, and 21% had fecal incontinence. Among cases, 46% were treated with budesonide. Compared to cases, controls had worse symptoms based on the Microscopic Colitis Disease Activity Index score with a median score of 3.0 (interquartile range 1.9-4.2) vs 2.3 (interquartile range 1.4-3.2) at 1-year follow-up. Controls had more frequent stools, urgency, fecal incontinence, and abdominal pain.

CONCLUSION

In a cohort of patients with biopsy-confirmed MC and diarrhea controls, we found that some cases remained unaware of their diagnosis, many cases had persistent symptoms, and controls had worse symptoms than cases. These findings suggest there are opportunities to improve management of this chronic disease.

Patients With Microscopic Colitis Are at Higher Risk of Major Adverse Cardiovascular Events: A Matched Cohort Study

BACKGROUND AND AIMS

Inflammatory diseases are associated with an increased risk of incident major adverse cardiovascular events (MACE). However, data on MACE are lacking in large population-based histopathology cohorts of microscopic colitis (MC).

METHODS

This study included all Swedish adults with MC without previous cardiovascular disease (1990-2017; N = 11,018). MC and subtypes (collagenous colitis and lymphocytic colitis) were defined from prospectively recorded intestinal histopathology reports from all pathology departments (n = 28) in Sweden. MC patients were matched for age, sex, calendar year, and county with up to 5 reference individuals (N = 48,371) without MC or cardiovascular disease. Sensitivity analyses included full sibling comparisons, and adjustment for cardiovascular medication and healthcare utilization. Multivariable-adjusted hazard ratios for MACE (any of ischemic heart disease, congestive heart failure, stroke, and cardiovascular mortality) were calculated using Cox proportional hazards modelling.

RESULTS

Over a median of 6.6 years of follow-up, 2181 (19.8%) incident cases of MACE were confirmed in MC patients and 6661 (13.8%) in reference individuals. MC patients had a higher overall risk of MACE outcomes compared with reference individuals (adjusted hazard ratio [aHR], 1.27; 95% confidence interval [CI], 1.21-1.33) and higher risk of its components: ischemic heart disease (aHR, 1.38; 95% CI, 1.28-1.48), congestive heart failure (aHR, 1.32; 95% CI, 1.22-1.43), and stroke (aHR, 1.12; 95% CI, 1.02-1.23) but not cardiovascular mortality (aHR, 1.07; 95% CI, 0.98-1.18). The results remained robust in the sensitivity analyses.

CONCLUSIONS

Compared with reference individuals, MC patients had a 27% higher risk of incident MACE, equal to 1 extra case of MACE for every 13 MC patients followed for 10 years.

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.

Adult-Onset Still's Disease (AOSD) Associated With Collagenous Colitis (CC) and Basedow's Disease: A Case Report

Adult-onset Still's disease (AOSD) is a rare auto-inflammatory syndrome of unknown etiology. Basedow's disease is a common cause of auto-immune hyperthyroidism. Collagenous colitis (CC) is a form of microscopic colitis (MC) affecting predominantly young women. While the etiology of the disease remains unclear, some studies suggest the role of auto-immunity. The association between AOSD and Basedow's disease has been reported in previous cases, suggesting auto-inflammation as a potential trigger of relapsing thyroid dysfunction. Although the co-existence of AOSD with inflammatory gastrointestinal disorders such as Crohn's disease and ulcerative colitis has also been described, we did not find any correlation with MC in the literature. We here describe the case of a woman having AOSD associated with Basedow's disease and CC.

Meta-analysis: Placebo rates in microscopic colitis randomised trials and applications for future drug development using a historical control arm

BACKGROUND

Effective medical therapies for patients with microscopic colitis (MC) who fail budesonide are lacking. However, conducting randomised controlled trials (RCTs) in MC has been challenging due to small sample sizes. Understanding placebo responses can help inform more efficient future trials.

AIMS

The aim of this study is to estimate clinical and histologic placebo response rates and to determine factors associated with placebo response in MC.

METHODS

EMBASE, MEDLINE, and CENTRAL were searched until 7 January 2022, to identify placebo-controlled RCTs in adult patients with MC. Clinical and histologic response in the placebo arms were pooled using random-effects models. Stratified analyses based on disease- and trial-level characteristics, leave-one-out meta-analysis, and cumulative meta-analysis were performed.

RESULTS

Twelve RCTs enrolling a total of 391 patients (placebo n = 163) with MC were included. Pooled clinical and histologic placebo response rates were 24.4% (95% CI: 12.4%-38.4%), I²  = 60.8%, p < 0.01, and 19.9% (95% CI: 5.3%-39.0%), I²  = 66.4%, p = 0.01 (tests for heterogeneity), respectively. Clinical response to placebo was numerically higher in patients with lymphocytic compared to collagenous colitis (39.9% vs. 19.8%, p = 0.08). Heterogeneity in clinical response to placebo was significantly reduced when the Miehlke 2014 RCT was excluded in the leave-one-out meta-analysis or when a more stringent secondary definition of response based on the Hjortswang criteria was applied.

CONCLUSIONS

Approximately one-quarter of patients in MC trials respond to placebo, although with substantial heterogeneity, reflecting the need for standardised outcome definitions and study designs for MC. This analysis also serves to inform future MC trials that may consider incorporating an external, historical placebo control arm, rather than directly randomising patients to placebo.

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.

Rheumatologic Associations of Microscopic Colitis: A Narrative Review

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

Course of Disease in Patients with Microscopic Colitis: A European Prospective Incident Cohort Study

BACKGROUND AND AIMS

The disease course of microscopic colitis [MC] is considered chronic but benign. However, this assumption is based on mainly retrospective studies, reporting on incomplete follow-up of selective cohorts. Systematic, prospective and unbiased data to inform patients and healthcare professionals on the expected course of the disease and real-life response to therapy are warranted.

METHODS

A prospective, pan-European, multi-centre, web-based registry was established. Incident cases of MC were included. Data on patient characteristics, symptoms, treatment and quality of life were systematically registered at baseline and during real-time follow-up. Four disease course phenotypes were discriminated and described.

RESULTS

Among 381 cases with complete 1-year follow-up, 49% had a chronic active or relapsing disease course, 40% achieved sustained remission after treatment and 11% had a quiescent course. In general, symptoms and quality of life improved after 3 months of follow-up. A relapsing or chronic active disease course was associated with significantly more symptoms and impaired quality of life after 1 year.

CONCLUSIONS

A minority of MC patients follow a quiescent disease course with spontaneous clinical improvement, whereas the majority suffer a chronic active or relapsing disease course during the first year after diagnosis, with persisting symptoms accompanied by a significantly impaired quality of life.

Microscopic colitis

Microscopic colitis (MC) is an inflammatory disease of the large intestine associated with urgent watery diarrhoea. MC may occur in people of all ages, although the disease primarily affects older women. Once believed to be rare, MC is now known to be a common cause of chronic watery diarrhoea in high-income countries, affecting 1 in 115 women and 1 in 286 men during their lifetime in Swedish population-based estimates. An inappropriate immune response to disturbances in the gut microenvironment is implicated in the pathogenesis of MC. Evidence also supports an underlying genetic basis for disease. The diagnosis of MC relies on clinical symptoms and microscopic assessment of colonic biopsy samples. MC is categorized histologically into collagenous colitis, lymphocytic colitis and their incomplete forms. The mainstay of treatment includes the use of budesonide, with or without adjunctive therapies, and withdrawal of offending drugs. Emerging studies suggest a role for biologicals and immunosuppressive therapies for the management of budesonide-refractory or budesonide-dependent disease. MC can have a substantial negative effect on patient quality of life. The outlook for MC includes a better understanding of the immune response, genetics and the microbiome in disease pathogenesis along with progress in disease management through robust clinical trials.

Microscopic Colitis: A Concise Review for Clinicians

Microscopic colitis (MC) is an inflammatory disease of the colon and a common cause of chronic watery diarrhea, predominantly in older patients. Microscopic colitis encompasses 2 different subtypes, lymphocytic colitis and collagenous colitis. The colon typically appears normal endoscopically in MC, and the diagnosis requires histologic evaluation. Whereas recent studies suggest that the incidence of MC has plateaued, given the aging of the population, the prevalence of MC will likely increase. Risk factors for MC include increasing age; female sex; presence of other autoimmune diseases; and possibly use of certain medications, including proton pump inhibitors, nonsteroidal anti-inflammatory drugs, selective serotonin reuptake inhibitors, and statins. The clinical presentation of MC is nonspecific and includes watery nonbloody diarrhea, nocturnal stools, fecal urgency, abdominal pain, arthralgias, and weight loss. The disease course of MC is variable; some patients experience occasional, intermittent symptoms, and others demonstrate more chronic and even progressive symptoms. The approach to treatment is similar for both lymphocytic colitis and collagenous colitis and should be guided by the severity of the patient's symptoms. Offending medications highly associated with MC should be eliminated as clinically possible. In patients with mild symptoms, antidiarrheals such as loperamide are the initial choice; for moderate-severe disease, budesonide is recommended for induction of clinical remission. In those with recurrent symptoms, low-dose budesonide may be required for maintenance therapy with close monitoring for potential adverse effects. In rare cases, immunomodulators may be required.

European guidelines on microscopic colitis: United European Gastroenterology and European Microscopic Colitis Group statements and recommendations

INTRODUCTION

Microscopic colitis is a chronic inflammatory bowel disease characterised by normal or almost normal endoscopic appearance of the colon, chronic watery, nonbloody diarrhoea and distinct histological abnormalities, which identify three histological subtypes, the collagenous colitis, the lymphocytic colitis and the incomplete microscopic colitis. With ongoing uncertainties and new developments in the clinical management of microscopic colitis, there is a need for evidence-based guidelines to improve the medical care of patients suffering from this disorder.

METHODS

Guidelines were developed by members from the European Microscopic Colitis Group and United European Gastroenterology in accordance with the Appraisal of Guidelines for Research and Evaluation II instrument. Following a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation methodology was used to assess the certainty of the evidence. Statements and recommendations were developed by working groups consisting of gastroenterologists, pathologists and basic scientists, and voted upon using the Delphi method.

RESULTS

These guidelines provide information on epidemiology and risk factors of microscopic colitis, as well as evidence-based statements and recommendations on diagnostic criteria and treatment options, including oral budesonide, bile acid binders, immunomodulators and biologics. Recommendations on the clinical management of microscopic colitis are provided based on evidence, expert opinion and best clinical practice.

CONCLUSION

These guidelines may support clinicians worldwide to improve the clinical management of patients with microscopic colitis.

Faecal microbiota transfer in patients with microscopic colitis - a pilot study in collagenous colitis

OBJECTIVES

Faecal microbiota transfer (FMT) consists of the infusion of donor faecal material into the intestine of patients with the aim to restore a disturbed gut microbiota.

METHODS

In this pilot study (NCT03275467), the effect of three repeated FMTs (day 0, two weeks, four weeks) was studied and followed up for six months in nine collagenous colitis (CC) patients, using two stool donors.

RESULTS

Five patients had an active disease at the time of baseline sampling. The primary endpoint (remission at six weeks, defined as <3 stools whereof <1 watery stool per day) was achieved by two of these patients, and by one at eight weeks. Overall, in all nine patients, FMT did not result in a significant reduction of watery stools, assessed by daily diary. However, diarrhoea (assessed by gastrointestinal symptom rating scale) was significantly improved at four (p = .038) and eight weeks (p = .038), indigestion at eight (p = .045) and 12 weeks (p = .006), disease-related worries at four (p = .027) and eight weeks (p = .027), and quality of life at six months (p = .009). FMT resulted in an increased number of lamina propria lymphocytes, possibly indicating an initial mucosal immune activation. No serious adverse events, no systemic effects, and no changes in faecal calprotectin and psychological symptoms were observed.

CONCLUSIONS

FMT is able to improve symptoms in a yet undefined subset of CC patients. Further studies could help to characterise this subset and to understand if these results can be generalised to all microscopic colitis patients.

Overview of microscopic colitis

Microscopic colitis encompasses both collagenous and lymphocytic colitis and is a relatively common condition with rising incidence. Diagnosis is by colonoscopy (which is usually normal but may show some mild changes) and biopsies which reveal characteristic histological findings. Symptoms include non-bloody diarrhoea with urgency which may be associated with faecal incontinence and abdominal pain. Microscopic colitis is associated with a reduced health-related quality of life, and treatment is aimed at symptom control. Medications linked with the development of microscopic colitis, including proton pump inhibitors, non-steroidal anti-inflammatory drugs and selective serotonin-reuptake inhibitors, should be discontinued. If symptoms persist, budesonide is a licensed treatment for microscopic colitis which has been shown to be effective in clinical trials and real-world practice.

Campylobacter concisus is prevalent in the gastrointestinal tract of patients with microscopic colitis

OBJECTIVES

Microscopic colitis (MC) is potentially induced by an inflammatory reaction to a luminal gut factor. The emerging pathogen Campylobacter concisus is associated with prolonged diarrhoea and subsequently increased risk of MC. We aimed to examine the prevalence of C. concisus in clinical samples from MC patients, analyse the subtypes collagenous colitis (CC) and lymphocytic colitis (LC), and characterise C. concisus isolates from MC patients by genomic sequencing.

METHODS

Mucosal biopsies were collected by sigmoidoscopy in 55 MC patients (CC n = 34, LC n = 21). Saliva and faecal samples were also collected. A two-step cultivation method and PCR established C. concisus prevalence. Biopsy and faecal isolates were sequenced for genomic analysis.

RESULTS

Cultivation revealed C. concisus in saliva 55/55, faeces 14/55 and biopsies 69/436, which was confirmed by PCR in faeces 28/55 and biopsies 215/430. Interestingly, biopsy prevalence was higher in CC patients than in LC patients both by cultivation (50/270 vs.19/166, p = .058) and by PCR (175/270 vs. 40/160, p < .0001). Long disease duration also affected biopsy prevalence both by cultivation 30/244 (<2 years) vs. 39/192 (>2 years) (p = .025) and by PCR 103/239 (<2 years) vs. 112/191 (>2 years) (p = .002). Genomic analysis on sixty biopsy and twenty faecal isolates revealed division into two clusters/genomospecies and a high presence of various, putative virulence genes (zot, exotoxin 9 and hcp).

CONCLUSIONS

Campylobacter concisus was prevalent in MC patients. Interestingly, the biopsy prevalence differed in biopsies from CC and LC patients and with regard to disease duration. Further studies are needed to elucidate this possible association.

Les colites microscopiques

Microscopic colitis is frequently found as a cause of chronic watery diarrhea in women after menopause. The disease can be associated with a medication side effect in half of the patients (non-steroidal anti-inflammatory drugs or proton pump inhibitors for instance). Colonic biopsies are mandatory for the diagnosis of microscopic colitis and should be performed in several locations of the colon. Management of microscopic colitis is first based on avoiding iatrogenic factors and smoking together with symptomatic treatment of diarrhea (loperamide, cholestyramine). In case of failure or severe symptoms, budesonide is the key treatment. The aim of the treatment is to achieve clinical remission, defined as less than 3 liquid stools per day, to improve quality of life. After a first course of budesonide, recurrence of diarrhea is frequent and a maintenance therapy can be prescribed for several months. In case of intolerance or refractoriness, second-line therapy (immunosuppressants, biological therapy, surgery) should be discussed in multidisciplinary team meeting.

All-cause and cause-specific mortality in microscopic colitis: a Danish nationwide matched cohort study

BACKGROUND

The long-term natural history of microscopic colitis remains uncertain.

AIM

To describe the mortality in a large unselected cohort of patients with microscopic colitis.

METHODS

All Danish patients above 18 years with an incident diagnosis of microscopic colitis from 2001 to 2018 were identified from nationwide registries and compared to age- and sex-matched controls (variable 1:10 ratio). Patients were categorised according to subtypes: lymphocytic colitis and collagenous colitis. The relative risk of death by any cause was analysed with Cox regression models estimating both crude and comorbidity-adjusted hazard ratios (HRs) with 95% confidence intervals (CIs). Cause-specific death was evaluated with cumulative incidence functions. An E-value was calculated to address the impact of unmeasured confounding.

RESULTS

The final cohort consisted of 14 024 patients with microscopic colitis. The mean follow-up was 5.8 (standard deviation SD, 2.9) years and the mean age at diagnosis was 61.1 (SD 13.9) years, 70% were women and 41% were diagnosed with lymphocytic colitis. The main results showed a 25% increased risk of all-cause death in patients with microscopic colitis; however, the relative risk was attenuated to 9% when adjusting for comorbidities (95% CI, 1.05-1.14). The E-value indicates that unmeasured confounding could explain the residual observed increased all-cause mortality. Mortality was significantly increased in patients with both lymphocytic colitis (HR 1.15; 95% CI, 1.08-1.23) and collagenous colitis (HR 1.06; 95% CI, 1.01-1.12) in fully adjusted analyses. The absolute difference in death between patients with microscopic colitis and matches was 0.9% at 1 year, 2.8% at 5 years, 5.0% at 10 years and 3.0% at 15 years. Cumulative incidence functions showed that patients with microscopic colitis were more likely to die due to smoking-related diseases including ischemic heart and lung diseases, but had a significant decreased risk of death due to colorectal cancers (P < 0.0001).

CONCLUSION

In an unselected large nationwide cohort of patients with microscopic colitis, the risk of death was significantly increased compared to the background population. However, the increased mortality seemed to be associated to a high burden of comorbidities and unmeasured life-style factors including smoking and not microscopic colitis per se.

Microscopic colitis: pathophysiology and clinical management

Microscopic colitis is a chronic inflammatory disease of the colon that frequently causes chronic watery diarrhoea that might be accompanied by abdominal pain, nocturnal diarrhoea, urgency, and faecal incontinence. These symptoms lead to poor quality of life and increased health-care costs. Diagnosis relies on histological examination of multiple biopsy samples from the colonic mucosa, which often show no or only few abnormalities on endoscopy. Two major histological subtypes can be distinguished-collagenous colitis and lymphocytic colitis-but incomplete and variant forms with fewer characteristic features have been reported. Here we summarise the latest evidence on epidemiology, pathogenesis, and risk factors, and discuss established and novel therapeutic options for clinical remission. Finally, we propose an updated treatment algorithm. Further prospective studies are needed to clarify the natural history of microscopic colitis, supported by validated criteria for the assessment of disease activity.

Undiagnosed microscopic colitis: a hidden cause of chronic diarrhoea and a frequently missed treatment opportunity

Microscopic colitis (MC) is a treatable cause of chronic, non-bloody, watery diarrhoea, but physicians (particularly in primary care) are less familiar with MC than with other causes of chronic diarrhoea. The colon in patients with MC is usually macroscopically normal. MC can only be diagnosed by histological examination of colonic biopsies (subepithelial collagen band >10 µm (collagenous colitis) or >20 intraepithelial lymphocytes per 100 epithelial cells (lymphocytic colitis), both with lamina propria inflammation). The UK National Health Service exerts downward pressure to minimise colonoscopy referrals. Furthermore, biopsies are often not taken according to guidelines. These factors work against MC diagnosis. In this review, we note the high incidence of MC (comparable to ulcerative colitis and Crohn's disease) and its symptomatic overlap with irritable bowel syndrome. We also highlight problems with the recommendation by National Health Service/National Institute for Health and Care Excellence guidelines for inflammatory bowel diseases that colonoscopy referrals should be based on a faecal calprotectin level of ≥100 µg/g. Faecal calprotectin is <100 µg/g in over half of individuals with active MC, building into the system a propensity to misdiagnose MC as irritable bowel syndrome. This raises important questions-how many patients with MC have already been misdiagnosed, and how do we address this silent burden? Clarity is needed around pathways for MC management; MC is poorly acknowledged by the UK healthcare system and it is unlikely that best practices are being followed adequately. There is an opportunity to identify and treat patients with MC more effectively.

Obesity and Weight Gain Since Early Adulthood Are Associated With a Lower Risk of Microscopic Colitis

BACKGROUND & AIMS

Obesity promotes intestinal inflammation and might contribute to the pathogenesis of inflammatory bowel disease. We examined the association between obesity and risk of microscopic colitis in a prospective cohort study.

METHODS

We collected data from 192,101 women enrolled in the Nurses' Health Study (NHS) (from 1986 through 2014) or the NHSII (from 1991 through 2015). Anthropomorphic and lifestyle information were self-reported biennially. Obesity was defined using body mass index (BMI). Microscopic colitis was confirmed by review of medical records. We used Cox proportional hazard models to estimate adjusted hazard ratios (aHRs) and 95% CIs.

RESULTS

Among the participants in the NHS and NHSII, we confirmed 244 cases of microscopic colitis during 4,223,868 person-years of follow-up evaluation. Higher BMI was associated inversely with risk of microscopic colitis (Ptrend < .001). Compared with women with BMIs ranging from 18.5 to 20.9 kg/m², the aHRs were 0.61 (95% CI, 0.41-0.91) for overweight women (BMI, 25-29.9 kg/m²) and 0.50 (95% CI, 0.32-0.79) for obese women (BMI ≥ 30 kg/m²). The aHR for each 5-kg/m² increase in BMI was 0.79 (95% CI, 0.69-0.90). Weight gain since early adulthood (age, 18 y) also was associated inversely with risk of microscopic colitis (Ptrend = .001). The aHR for each 10-kg weight gain since early adulthood was 0.85 (95% CI, 0.77-0.94). The associations were not modified by age, cohort, physical activity, or smoking status (all Pinteraction ≥ .26).

CONCLUSIONS

Unlike many other immune- and metabolic-related disorders, obesity and weight gain since early adulthood were associated with a lower risk of microscopic colitis, based on an analysis of participants in the NHS and NHSII.

Single-centre experience with anti-tumour necrosis factor treatment in budesonide-refractory microscopic colitis patients

Background

Microscopic colitis is an inflammatory bowel disease that causes chronic, watery diarrhoea. Microscopic colitis is usually effectively treated with budesonide, but some patients are refractory. Data on alternative treatments are sparse.

Aims

The purpose of this study was to retrospectively evaluate outcome of microscopic colitis patients receiving anti-tumour necrosis factor therapy at our centre.

Methods

Treatment results, including side effects, for all microscopic colitis patients receiving anti-tumour necrosis factor therapy were registered at week 12 and at end of follow-up. Clinical remission was defined as a mean of <3 stools and <1 watery stools/day/week and clinical response as a 50% reduction of mean stool frequency/day/week. Induction and maintenance treatment was either adalimumab or infliximab.

Results

The study cohort comprised 18 patients; mean age at diagnosis was 47 years (range 19-77). Ten and eight patients, respectively, received adalimumab and infliximab as first-line anti-tumour necrosis factor; seven patients received second-line anti-tumour necrosis factor due to non-response, loss of response or side effects. At week 12, 9/18 patients had achieved remission, 6/18 were responders and 3/18 were non-responders. Of the nine remission patients, 3/18 (16%) had long-lasting clinical remission post-induction therapy alone. Five patients (28%) (one first-line, four second-line anti-tumour necrosis factor) were in remission and one patient (6%) responded to maintenance treatment; follow-up was mean 22 (range 4-60) months. Six patients (33%) had minor, reversible side effects.

Conclusions

Over half of budesonide-refractory microscopic colitis patients can achieve clinical remission or response on anti-tumour necrosis factor agents. Prospective studies are mandatory to evaluate the efficacy and safety of anti-tumour necrosis factor treatments in budesonide-refractory microscopic colitis.

Budesonide treatment for microscopic colitis: systematic review and meta-analysis

Microscopic colitis (MC), encompassing lymphocytic and collagenous colitis, is a common cause for chronic nonbloody diarrhoea, which impacts significantly on the quality of life for patients. Despite increasing awareness of the condition and its treatment, there is considerable variation in therapeutic approaches. To conduct a systematic review and meta-analysis on the efficacy and safety of budesonide in the treatment of MC. We searched Medline, Embase and Central databases using predefined search methodology for randomised trials using budesonide in the treatment of MC. We extracted data, on the efficacy and safety of budesonide, from studies identified that met the feasibility for analysis criteria. These data were pooled with a fixed effects model. Nine studies met the inclusion criteria for analysis. The pooled odds ratios (ORs) for a response to budesonide therapy at induction and maintenance were 7.34 [95% confidence interval (CI): 4.08-13.19] and 8.35 (95% CI: 4.14-16.85) respectively. Histological response rates were superior in budesonide-treated patients compared to placebo following induction (OR: 11.52; 95% CI: 5.67-23.40) and maintenance treatment (OR: 5.88; 95% CI: 1.90-18.17). There was no difference in adverse events. Significant relapse rates (>50%) were observed following treatment cessation with no difference noted between the budesonide or the placebo-treated patients. Budesonide is an effective treatment option for MC for achieving induction and maintenance of both clinical and histological response. High relapse rates on treatment cessation were observed.

Microscopic colitis: Struggling with an invisible, disabling disease

Background and aims

Microscopic colitis causes chronic or recurrent nonbloody, watery diarrhoea, which is associated with urgency, faecal incontinence and abdominal pain. The patient's health‐related quality of life is often impaired. In microscopic colitis, health‐related quality of life has been studied using questionnaires originally constructed and validated for patients with inflammatory bowel disease. The aim of this study was to explore the impact of microscopic colitis on everyday life.

Methods and results

Inductive, qualitative, semi‐structured interviews were performed with 15 persons suffering from microscopic colitis. Content analysis was used to explore the impact of the condition on everyday life. The study followed the consolidated criteria for reporting qualitative research. The qualitative inductive content analysis generated one theme and five subthemes. The theme was “struggling with an invisible, disabling disease.” The five subthemes were as follows: physical experience of bowel function; associated symptoms affecting quality of life; impact of the disease on everyday life; disease‐related worry; and strategies for managing everyday life.

Conclusions

The semi‐structured interviews with persons suffering from microscopic colitis provided a wide spectrum of answers to the question of how everyday life is affected. Microscopic colitis can be a disabling life experience, and patients develop different strategies to adapt, cope and regain their previous performance level.

Relevance to clinical practice

There are new and interesting findings in our study that everyday life still remains affected even when patients are in remission. These findings have relevance in clinical practice and may create a better understanding of the patient's symptoms and situation.

Microscopic colitis: a narrative review with clinical approach

Microscopic colitis (MC) is diagnosed in presence of microscopic alterations of colonic mucosa, in patients without macroscopic lesions who referred for chronic diarrhea. The two types of MC are lymphocytic colitis (LC) and collagenous colitis (CC), but it is unclear whether these are the different expression of one unique disease or if they are distinct conditions. Today, although MC represents a consistent health problem, being responsible for a large part of gastroenterological consultations for diarrhea, it remains often underestimated. The detailed pathogenesis of MC has not been determined yet. Probably, it is the result of an interaction between individual, environmental and genetic factors. The most relevant risk factor for the development of MC is the use of certain drugs (such as non-steroidal anti-inflammatory drugs [NSAIDs], proton pump inhibitors [PPIs], selective serotonin reuptake inhibitors, beta-blockers, statins). Smoking is another relevant factor reported as associated with the development of MC. Diagnosis needs the execution of a colonoscopy in patients complaining about chronic diarrhea and abdominal pain. The crucial role is played by histology: MC is characterized by the presence of colonic mucosal lymphocytic infiltrate, with intraepithelial lymphocytes ≥20 per 100 enteric surface cells, in CC there is a typical subepithelial collagen layer, whose thickness is ≥10 μm. We carried out a review of the current literature to rule out what is new on epidemiology, diagnosis and therapy of MC.

Management of microscopic colitis: challenges and solutions

Microscopic colitis (MC) is a chronic inflammatory bowel disease characterized by nonbloody diarrhea in the setting of normal appearing colonic mucosa. MC has two main subtypes based on histopathologic features, collagenous colitis and lymphocytic colitis. Management of both subtypes is the same, with treatment goal of reducing the number of bowel movements and improving consistency. First-line treatment involves counseling the patient about decreasing their risk factors, like discontinuing smoking and avoiding medications with suspected association such as NSAIDs, proton pump inhibitor, ranitidine, and sertraline. Starting loperamide for immediate symptomatic relief is used as an adjunct to therapy with glucocorticoids. Budesonide is considered first-line treatment for MC given its favorable side effect profile and good efficacy, though relapse rates are high. Systemic glucocorticoids should be reserved to patients unable to take budesonide. In glucocorticoid refractory disease, medications that have been tried include cholestyramine, bismuth salicylate, antibiotics, probiotics, aminosalicylates, immunomodulators, and anti-tumor necrosis factor-alpha inhibitors. More research is needed for the creation of a systematic stepwise approach for relapsing and refractory disease.

Proinflammatory Sulfur-Reducing Bacteria Are More Abundant in Colonic Biopsies of Patients with Microscopic Colitis Compared to Healthy Controls

BACKGROUND

Microscopic colitis (MC), a subtype of inflammatory bowel disease, is a chronic condition of unknown etiology. Recent evidence has linked MC with intriguing changes in the stool microbiota, which may be linked to disease pathogenesis. The composition of the mucosal microbiome in patients with MC remains unclear.

METHODS

We performed a cross-sectional study comparing colonic tissue samples from patients with MC to those of healthy controls at the Michael E. DeBakey VA Medical Center. We included adults older than 18 who underwent a colonoscopy with biopsies to evaluate chronic diarrhea. Cases were defined by histology consistent with MC and controls by the absence of histologic disease. We conducted structured chart review to exclude other gastrointestinal diseases and obtain demographic (age, sex, race) and clinical (duration of symptoms and concurrent medications) information for cases and controls. We extracted bacterial DNA from formalin-fixed paraffin-embedded tissue samples and sequenced the v4 region of the 16S rRNA gene. Operational taxonomic unit (OTU) clustering was performed using UPARSE, and OTUs were assigned using the SILVA database. Statistical analysis was performed in QIIME and LEfSe. Comparisons with FDR-adjusted p values of less than 0.05 were considered statistically significant.

RESULTS

We included 20 MC patients and 20 controls with mean ages of 62 and 54, respectively. Most cases were White (95%), 60% had symptoms for greater than 12 months, and 50% were taking PPIs and NSAIDs at the time of their diagnosis. Compared to controls, MC patients had a significant increase in the proinflammatory sulfur-reducing bacterial family Desulfovibrionales. The Coriobacteriaceae family, abundant in the healthy gut, was significantly decreased in MC cases. There was also an increase in the genus Actinomyces in MC patients on PPI and an increase in the class Bacilli among those taking NSAIDs.

DISCUSSION

Patients with MC have an increase in the proinflammatory family Desulfovibrionales. Actinomyces and Bacilli were associated with medications (PPI and NSAID) known to increase the risk of MC. Our findings may have important implications for understanding the pathogenesis of MC.

Efficacy and Safety of Budesonide, vs Mesalazine or Placebo, as Induction Therapy for Lymphocytic Colitis

BACKGROUND & AIMS

Lymphocytic colitis is a common cause of chronic, nonbloody diarrhea. However, the effects of treatment are unclear and randomized placebo-controlled trials were requested in a Cochrane review. We performed a randomized, placebo-controlled, multicenter study to evaluate budesonide and mesalazine as induction therapy for lymphocytic colitis.

METHODS

Patients with active lymphocytic colitis were randomly assigned to groups given budesonide 9 mg once daily (Budenofalk granules), mesalazine 3 g once daily (Salofalk granules), or placebo for 8 weeks in a double-blind, double-dummy design. The primary endpoint was clinical remission, defined as ≤21 stools (including ≤6 watery stools), in the 7 days before week 8.

RESULTS

The final analysis included 57 patients (19 per group). Most patients were female (72%) and the mean age was 59 years. The proportion of patients in clinical remission at week 8 was significantly higher in the budesonide group than in the placebo group (intention-to-treat analysis, 79% vs 42%; P = .01). The difference in proportions of patients in clinical remission at week 8 between the mesalazine (63%) and placebo groups was not significant (P = .09). The proportion of patients with histologic remission at week 8 was significantly higher in the budesonide group (68%) vs the mesalazine (26%; P = .02) or placebo (21%; P = .008) groups. The incidence of adverse events was 47.4% in the budesonide group, 68.4% in the mesalazine group, and 42.1% in the placebo group.

CONCLUSIONS

In a randomized multicenter study, we found oral budesonide 9 mg once daily to be effective and safe for induction of clinical and histologic remission in patients with lymphocytic colitis, compared with placebo. Oral mesalazine 3 g once daily was not significantly better than placebo. ClinicalTrials.gov no: NCT01209208.

Fatigue and its associated factors in microscopic colitis

BACKGROUND

Fatigue is a well-recognized symptom in patients with inflammatory bowel disease and irritable bowel syndrome (IBS), and has been associated with psychological comorbidity and impaired quality of life in both. However, features associated with fatigue in patients with microscopic colitis (MC) are less clear.

MATERIALS AND METHODS

We conducted a cross-sectional survey of patients with a new diagnosis of MC including levels of anxiety, depression, somatization, quality of life, and IBS-type symptoms. Levels and impact of fatigue were assessed using the Inflammatory Bowel Disease Fatigue self-assessment scale. Mean scores were compared against various patient characteristics, and were also correlated with anxiety, depression, somatization, and quality-of-life scores.

RESULTS

In total, 129 patients with MC diagnosed between 2010 and 2015 returned completed postal questionnaires. Common histological subtypes were collagenous colitis (53.5%, n = 69) and lymphocytic colitis (38.8%, n = 50). Higher mean fatigue severity and impact scores were associated with the presence of irritable-bowel-syndrome-type symptoms, abnormal levels of anxiety and depression, and high levels of somatization (p < 0.0001 for all), but those reporting ongoing symptoms attributable to MC did not report significantly higher scores. There were significant positive correlations between total anxiety, depression, or somatization scores and fatigue severity and impact scores, and significant negative correlations with quality-of-life measures (p < 0.001 for all).

CONCLUSIONS

Fatigue in MC appears to be associated with reporting IBS-type symptoms, psychological comorbidity and impaired quality of life. It may therefore represent an important target for treatment.

High prevalence of irritable bowel syndrome-type symptoms in microscopic colitis: implications for treatment

BACKGROUND

Patients with microscopic colitis (MC) often present with abdominal pain and diarrhoea, and previous data suggest that there may be overlap between MC and irritable bowel syndrome (IBS). We evaluated the prevalence of IBS-type symptoms in patients with MC, and assess the impact of these symptoms on psychological health and quality of life.

METHODS

We conducted a cross-sectional survey of individuals with a histological diagnosis of MC, collecting demographic data, Rome III IBS-type symptoms, and mood, somatization, and quality of life data.

RESULTS

In total, 151 (31.6%) of 478 individuals with a new diagnosis of MC completed questionnaires, 52 (34.4%) of whom reported IBS-type symptoms. The commonest histological subtype was collagenous colitis (51.7%, n = 78), followed by lymphocytic colitis (39.1%, n = 59). Individuals with IBS-type symptoms had significantly higher levels of anxiety [Hospital Anxiety and Depression Scale (HADS) anxiety score 8.6 versus 5.1, p < 0.001], depression (HADS depression score 6.2 versus 3.6, p = 0.001), and somatoform-type behaviour (Patient Health Questionnaire 15 score 12.7 versus 8.0, p < 0.001) compared with individuals who did not. Those with IBS-type symptoms scored significantly worse across all domains of the 36-item Short Form questionnaire, except for physical functioning.

CONCLUSIONS

More than one third of individuals with MC reported IBS-type symptoms, although whether this is due to ongoing inflammation is unclear. These individuals had higher levels of anxiety, depression, and somatization, and impaired quality of life. Identifying concomitant IBS in individuals with MC may have important implications for management decisions.

Development of a Microscopic Colitis Disease Activity Index: a prospective cohort study

OBJECTIVE

Microscopic colitis (MC) is a common cause of chronic diarrhoea, often with additional symptoms. No validated instruments exist to assess disease activity in MC, making it difficult to compare efficacy of treatments between clinical trials. We aimed to identify clinical features that independently predicted disease severity and create a Microscopic Colitis Disease Activity Index (MCDAI).

DESIGN

Patients with MC were prospectively administered a survey assessing their GI symptoms and the IBD Questionnaire (IBDQ). A single investigator also scored a physician global assessment (PGA) of disease severity on a 10-point scale. Multiple linear regression identified which symptoms best predicted the PGA. These symptoms were then combined in a weighted formula to create the MCDAI. The relationship between MCDAI and the IBDQ was investigated.

RESULTS

Of the 175 patients enrolled, 13 (7.4%) did not complete the survey. The remaining 162 had a median age of 66 years (range, 57-73) and 74% were female. Several clinical features were independently associated with PGA (number of unformed stools daily, presence of nocturnal stools, abdominal pain, weight loss, faecal urgency and faecal incontinence). These parameters were combined to create the MCDAI, which strongly predicted the PGA (R²=0.80). A 1-unit decrease in disease activity (ΔMCDAI) was associated with a 9-unit increase in quality of life (ΔIBDQ).

CONCLUSIONS

The MCDAI strongly predicted the PGA and correlated with a validated measure of quality of life. Several symptoms in addition to diarrhoea are associated with disease severity in MC.

Endoscopic findings and colonic perforation in microscopic colitis: A systematic review

INTRODUCTION

Microscopic colitis (MC) is a clinical syndrome of severe watery diarrhea with few or no endoscopic abnormalities. The incidence of MC is reported similar to that of other inflammatory bowel diseases. The need for histological confirmation of MC frequently guides reimbursement health policies. With the advent of high-definition (HD) coloscopes, the incidence of reporting distinct endoscopic findings in MC has risen. This has the potential to improve timely diagnosis and cost-effective MC management and diminish the workload and costs of busy modern endoscopy units.

METHODS

Publications on distinct endoscopic findings in MC available until March 31st, 2017 were searched systematically (electronic and manual) in PubMed database. The following search terms/descriptors were used: collagenous colitis (CC) OR lymphocytic colitis (LC) AND endoscopy, colonoscopy, findings, macroscopic, erythema, mucosa, vasculature, scars, lacerations, fractures. An additional search for MC AND perforation was made.

RESULTS

Eighty (n=80) articles, predominantly single case reports (n=49), were found. Overall, 1582 (1159F; 61.6±14.1 years) patients (pts) with MC and endoscopic findings were reported. The majority of articles (n=62) were on CC (pts 756; 77.5% females). We identified 16 papers comprising 779 pts (69.2% females) with LC and 7 articles describing 47 pts (72.3% females) diagnosed as MC. The youngest patient was 10 and the oldest a 97-year-old. Aside diarrhea, symptoms included abdominal pain, weight loss, bloating, flatulence, edema and others. In the study group we found 615 (38.8%) persons with macroscopic lesions in gut. Isolated linear ulcerations were identified in 7 pts (1.1%) while non-ulcerous lesions i.e. pseudomembranes, a variable degree of vasculature pruning & dwindling, mucosal lacerations and abnormalities such as erythema/edema/nodularity, or surface textural alteration in 608 pts (98.1%). The location of endoscopic findings was not reported in 27 articles. The distinct endoscopic findings were described in the left (descending, sigmoid, rectum - 10/21/11 studies), right (cecum, ascending - 7/7 studies), transverse colon (n=12), as well as duodenum (n=4), and terminal ileum (n=2). In 17 (1.1%) pts colonic perforation occurred.

CONCLUSION

Endoscopic findings are recognized with increased frequency in pts with MC. This could improve MC diagnosis by prompting a more extensive biopsy protocol in such cases and an earlier initiation of treatment. Procedure-related perforation has been reported in this group; therefore, cautious air insufflation is advisable when endoscopic findings are recognised.

Macroscopic findings, incidence and characteristics of microscopic colitis in a large cohort of patients from the United Kingdom

OBJECTIVE

Microscopic colitis (MC) is classically associated with normal or near-normal endoscopic appearances. However, non-specific macroscopic findings have been described, the importance of biopsy location for confirming a diagnosis of MC is unclear, and reported incidence data from the United Kingdom are limited. This study was designed to assess macroscopic features, incidence, demographics, and location and positivity of biopsy samples in MC.

MATERIALS AND METHODS

Retrospective, cross-sectional study of individuals with newly diagnosed MC.

RESULTS

From 2010 to 2015, 540 cases of MC were reported. Macroscopic findings occurred in 16.5% (n = 89) cases, with trends towards increased frequency of ulceration or linear scarring in collagenous colitis (CC). The mean incidence of MC was 11.3 per 100,000 population/year, including 291 (53.9%) with CC (incidence 6.1 per 100,000/year), 203 (37.6%) with lymphocytic colitis (incidence 4.2 per 100,000/year) and 46 (8.5%) with MC, not otherwise specified. Most individuals were female (70.2%). Common features in patients with MC included symptom duration <6 months, weight loss, abdominal pain and use of proton pump inhibitors, statins, or non-steroidal anti-inflammatory drugs. In individuals with right- and left-sided biopsies taken, 98.2% had diagnostic features in both. However, rectal biopsies were only positive in 88.7%.

CONCLUSIONS

One in six patients with MC demonstrated distinct macroscopic findings at colonoscopy. Our data confirm a female preponderance in MC, a relatively short symptom duration and use of certain drugs as common features. Both right- and left-sided biopsies were frequently positive, suggesting flexible sigmoidoscopy and biopsy could confirm a diagnosis in certain individuals.

Immune modulator therapy for microscopic colitis in a case series of 73 patients

BACKGROUND

Microscopic colitis (MC) is a common cause of chronic diarrhoea. Various treatment options have been described, but there are limited data describing outcomes of corticosteroid-sparing treatments.

AIM

To evaluate the outcomes of patients with active MC treated with immune modulators.

METHODS

All patients seen at Mayo Clinic, Rochester between January 1, 1997 and November 30, 2016 with a histological diagnosis of MC were identified. Patients treated with an immune modulator of interest were selected and clinical outcomes recorded.

RESULTS

Seventy-three MC patients (50 collagenous colitis and 23 lymphocytic colitis) with a median disease duration of 24 months (range, 7-60) were included. The indications for treatment were budesonide-refractoriness in 66%, budesonide dependence in 29%, and budesonide intolerance in 5%. Median age was 51.8 years (range, 43.4-63.1) and 61 (84%) were female. Thiopurines were used in 49 patients (67%) for a median of 4 months (range, 1.5-15). Complete and partial response occurred in 43% and 22% respectively. Adverse effects resulting in therapy cessation occurred in 17 patients (35%). Twelve patients (16%) were treated with methotrexate for a median of 14 months (3-18.8). Complete and partial response occurred in 58% and 17%, respectively. Anti-TNF therapy was used in 10 patients (14%) for a median of 4 months (range, 2.3-5.5). Complete response occurred in four patients and partial response in four patients.

CONCLUSIONS

The majority of patients with active MC responded to thiopurines, methotrexate, or anti-TNF therapy. Larger controlled studies are required to confirm the efficacy and safety of these medications in MC.

Family history, comorbidity, smoking and other risk factors in microscopic colitis: a case-control study

OBJECTIVES

Data on heredity, risk factors and comorbidity in microscopic colitis, encompassing collagenous colitis (CC) and lymphocytic colitis (LC), are limited.

AIM

The aim was to carry out a case-control study of family history, childhood circumstances, educational level, marital status, smoking and comorbidity in microscopic colitis.

METHODS

A postal questionnaire was sent in 2008-2009 to microscopic colitis patients resident in Sweden and three population-based controls per patient, matched for age, sex and municipality.

RESULTS

Some 212 patients and 627 controls participated in the study. There was an association with a family history of microscopic colitis in both CC [odds ratio (OR): 10.3; 95% confidence interval (CI): 2.1-50.4, P=0.004] and LC (OR not estimated, P=0.008). Current smoking was associated with CC [OR: 4.7; 95% CI: 2.4-9.2, P<0.001) and LC (OR: 3.2; 95% CI: 1.6-6.7, P=0.002). The median age at diagnosis was around 10 years earlier in ever-smokers compared with never-smokers.CC was associated with a history of ulcerative colitis (UC) (OR: 8.7, 95% CI: 2.2-33.7, P=0.002), thyroid disease (OR: 2.3; 95% CI: 1.1-4.5, P=0.02), coeliac disease (OR: 13.1; 95% CI: 2.7-62.7, P=0.001), rheumatic disease (OR 1.9; 95% CI: 1.0-3.5, P=0.042) and previous appendicectomy (OR: 2.2; 95% CI: 1.3-3.8, P=0.003), and LC with UC (OR: 6.8; 95% CI: 1.7-28.0, P=0.008), thyroid disease (OR: 2.4; 95% CI: 1.1-5.4, P=0.037) and coeliac disease (OR: 8.7; 95% CI: 2.8-26.7, P<0.001).

CONCLUSION

Association with a family history of microscopic colitis indicates that familial factors may be important. The association with a history of UC should be studied further as it may present new insights into the pathogenesis of microscopic colitis and UC.

Current Approach to the Evaluation and Management of Microscopic Colitis

PURPOSE OF REVIEW

Microscopic colitis is a common cause of chronic watery diarrhea, particularly in the elderly. The accompanying symptoms, which include abdominal pain and fatigue, can markedly impair patients' quality of life. Diagnosis is based upon characteristic histologic findings of the colonic mucosa. This review focuses on the current approach to evaluation and management of patients with microscopic colitis.

RECENT FINDINGS

Although the incidence of microscopic colitis has been increasing over time, recent epidemiological studies show stabilization at 21.0-24.7 cases per 100,000 person-years. Recent research has further expanded our knowledge of the underlying pathophysiology and emphasized the entity of drug-induced microscopic colitis and the association with celiac disease. Two recent randomized studies have confirmed the effectiveness of oral budesonide for both induction and maintenance treatment of microscopic colitis and is now endorsed by the American Gastroenterological Association as first-line treatment. The incidence of microscopic colitis has stabilized at just over 20 cases per 100,000 person-years. Celiac disease and drug-induced microscopic colitis should be considered in all patients diagnosed with microscopic colitis. There are a number of treatments available for patients with microscopic colitis; however, budesonide is the only option well studied in controlled trials and is effective for both induction and maintenance treatment.

Optimization of a Scoring System to Predict Microscopic Colitis in a Cohort of Patients With Chronic Diarrhea

GOALS

Our aim was to develop a scoring system to predict risk of microscopic colitis (MC), to identify patients at low risk, potentially avoiding unnecessary biopsies.

BACKGROUND

Patients with chronic diarrhea often undergo colonoscopy with biopsy, but few have histologic abnormalities.

STUDY

We conducted a retrospective study of patients with chronic diarrhea and a macroscopically normal colonoscopy at our institution over a 9-month period. Multivariable logistic regression assessed the association between predictors and the presence of biopsy-proven MC.

RESULTS

The derivation cohort included 617 patients. Median age was 55.1 (39.6 to 68.1) years; 397 (64.3%) were female and 81 (13.1%) had MC. Age ≥55 years, duration of diarrhea ≤6 months, ≥5 bowel movements per day, body mass index <30 kg/m, current smoking, and current use of selective serotonin reuptake inhibitors/serotonin-norepinephrine reuptake inhibitorss and non-steroidal anti-inflammatory drugs were independently associated with MC. A score of ≥10 points in our scoring system, yielded an area under the ROC curve (AUC) of 0.83 with a sensitivity of 93% and specificity of 49% in predicting which patients have MC. The negative predictive value (NPV) was 97.8% (95.0% to 99.1%).In the validation cohort, the scoring system performed similarly (AUC 0.79, sensitivity 91%, specificity 49%, NPV 97%). By avoiding biopsies in patients at low risk of having MC, costs associated with colon biopsies could be reduced by almost 43%.

CONCLUSION

This scoring system including 7 clinical variables was able to identify patients unlikely to have MC, with excellent sensitivity, reasonable specificity, and a high NPV, translating into important potential cost savings.

Clinical and immunologic effects of faecal microbiota transplantation in a patient with collagenous colitis

One to six percent of patients with microscopic colitis are refractory to medical treatment. The effect of faecal microbiota transplantation (FMT) in active collagenous colitis (CC) has, to the best of our knowledge, never been reported before. Here, we report the effect of repeated FMT in a patient with CC. The patient presented with severe symptoms including profuse diarrhea and profound weight loss. Although she responded to budesonide in the beginning, she became gradually refractory to medical treatment, and was therefore treated with FMT. The patient remained in remission for 11 mo after the third faecal transplantation. The immunomodulatory effect of the therapy was evaluated using flow cytometry, which showed alterations in the profile of intraepithelial and lamina propria lymphocyte subsets after the second transplantation. Our observations indicate that FMT can have an effect in CC, which support the hypothesis that luminal factors, influencing the intestinal microbiota, are involved in the pathogenesis of CC.

Diagnosis and Management of Microscopic Colitis

Microscopic colitis (MC) is a relatively common cause of chronic watery diarrhea, especially in older persons. Associated symptoms, including abdominal pain and arthralgias, are common. The diagnosis is based upon characteristic histological findings in the presence of diarrhea. The two types of MC, collagenous and lymphocytic colitis, share similar clinical features, with the main difference being the presence or absence of a thickened subepithelial collagen band. There are several treatment options for patients with MC, although only budesonide has been well studied in multiple controlled clinical trials. This review will describe the clinical features, epidemiology, pathophysiology, diagnostic criteria, and treatment of patients with MC.

Prevalence and Natural History of Microscopic Colitis: A Population-Based Study With Long-term Clinical Follow-up in Terrassa, Spain

BACKGROUND AND AIMS

Few studies have assessed the prevalence of microscopic colitis (MC) and the natural history of this disease is not well known. The aim of this study was to evaluate the prevalence rate of MC, the burden of disease in terms of loss of health and the long-term natural history of MC in a population-based cohort study.

METHODS

Cases were obtained from the pathology department registry Hospital Universitari Mutua Terrassa. Belonging to the catchment area, maintaining residence in that area, and being alive on August 31, 2014 were confirmed for each case. Adjusted prevalence rates were calculated. Current active drugs for MC and diarrhoea persistence in every patient were recorded.

RESULTS

The prevalence rate of MC was 107 per 10(5) inhabitants. The rate of patients with active disease, i.e. those representing the true burden of the disease in terms of loss of health, was 31 per 10(5) inhabitants. After a follow-up of 7.8±0.38 years from diagnosis, 75% of the patients experienced prolonged disease remission, defined as clinical remission without requiring drugs for 1 year or more. The only variable associated with prolonged MC remission was how clinical remission was achieved (spontaneous 93.3%, drug-induced, 60.5%; odds ratio 8.4, 95% confidence interval 2.7-26).

CONCLUSIONS

The rate of patients with MC and active disease, which represents the true disease burden in terms of loss of health, is low. Most patients with MC experience prolonged disease remission, with key differences between spontaneous and drug-induced clinical remission.

Systematic review with meta-analysis: diagnostic overlap of microscopic colitis and functional bowel disorders

BACKGROUND

Microscopic colitis shares certain common clinical manifestations with functional bowel disorders, especially diarrhoea-dominant irritable bowel syndrome (IBS) and functional diarrhoea. However, the exact relationship between microscopic colitis and functional bowel disorders has not been systematically assessed.

AIM

To conduct a systematic review and meta-analysis on the diagnostic overlap between functional bowel disorders and microscopic colitis.

METHODS

We searched MEDLINE, EMBASE and SCOPUS databases, as well as the abstract books of the major gastroenterology meetings, to investigate the prevalence of microscopic colitis among patients with functional bowel disorders (considering all subtypes of both disorders) and vice versa. Data were pooled with a random-effects model.

RESULTS

Of 227 references identified, data were collected from 26 studies and a total of 5,099 adult patients. The pooled prevalence any type of functional bowel disorders in patients who present diagnostic criteria of microscopic colitis was 39.1% (95% CI: 22.8-56.6%; I² : 97%) and was higher for lymphocytic colitis than for collagenous colitis (40.7% vs. 28.4%, respectively; P = 0.58). The prevalence of microscopic colitis in functional bowel disorders patients was 7% (95% CI: 3.6-11.4%), reaching 9.8% (95% CI: 4.4-17.1%; I² : 95%) in patients exhibiting diarrhoea-dominant IBS, nonsignificantly higher than microscopic colitis rates among patients with constipation-dominant IBS (1.3%) or mixed-dominant IBS (1.9%).

CONCLUSIONS

There is a significant overlap of symptoms between microscopic colitis and functional bowel disorders, especially in diarrhoeal subtypes. The high proportion of microscopic colitis among diarrhoea-dominant functional syndromes should serve as a call for more active diagnosis in selected patients.

The Temporal Evolution of Histological Abnormalities in Microscopic Colitis

BACKGROUND AND AIMS

Microscopic colitis (MC) is a common cause of chronic watery diarrhoea but long-term follow-up data are sparse.

METHODS

We performed a retrospective review of health records and all pathology reports in a regional cohort of patients with MC to describe the change in pre- and post-diagnostic colon biopsies.

RESULTS

MC was diagnosed in 468 patients with collagenous colitis (CC), 361 with lymphocytic colitis (LC) and 226 with incomplete MC (MCi). The 2014 incidence of CC, LC and MCi was 14.5, 14.9 and 5 per 10(5). Biopsies from both right and left colon were obtained in 237 (51%) patients with CC, 200 (55%) with LC and 107 (47%) with MCi. The diagnostic sensitivities of both left- and right-sided biopsies for MC were high and did not differ. Pre-diagnostic biopsies were obtained in 150 patients and lamina propria inflammation was described in 59, 47 and 43% of patients with a diagnosis of CC, LC and MCi respectively within 1 year, while histology was normal in 16, 13 and 21%. Post-diagnostic biopsies were obtained in 283 patients. MC persisted for up to one year in 77% with CC, 64% with LC and 45% with MCi, of whom 6, 9 and 18% respectively changed to a different MC subgroup.

CONCLUSIONS

Colonic biopsies obtained prior to the MC diagnosis often revealed increased lamina propria inflammation. The pathological changes of CC and LC are more persistent than those of MCi. Biopsies from the descending or sigmoid colon are sufficient to elucidate whether a patient with chronic watery diarrhoea has MC.

Optimal management of collagenous colitis: a review

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