Increased risk of microscopic colitis with use of proton pump inhibitors and non-steroidal anti-inflammatory drugs

PROTON-PUMP INHIBITORS ARE ASSOCIATED WITH AN INCREASED RISK OF MICROSCOPIC COLITIS: A POPULATION-BASED STUDY AND REVIEW OF THE LITERATURE

BACKGROUND

•The study evaluated the risk of developing microscopic colitis and its subtypes in patients on PPI therapy.

BACKGROUND

•Using a large multicenter database, a retrospective cohort analysis was conducted, excluding patients with autoimmune diseases, and adjusting for confounders.

BACKGROUND

•An increased risk of developing microscopic colitis was associated with female gender, smoking, and the use of PPI, SSRI, and NSAIDs.

BACKGROUND

•The use of PPI represented the highest odds of developing microscopic colitis.

BACKGROUND

Microscopic colitis is a relatively new diagnosis that was first described in the 1980s. Patients usually present with chronic watery and non-bloody diarrhea and are typically characterized by an unremarkable gross appearance of the colon on lower endoscopy while having evidence of lymphocytic infiltration of the lamina propria and the epithelium on histology. Two subtypes have been described in the literature: Collagenous colitis, with marked thickening of the subepithelial layer, and Lymphocytic colitis. Multiple risk factors such as female gender, older age and celiac disease have been associated with this entity. A few studies have found an association between microscopic colitis and proton-pump inhibitor (PPI). The aim of our study was to evaluate the risk of developing microscopic colitis and its subtypes for patients who are on PPI therapy.

METHODS

A validated multicenter and research platform database of more than 360 hospitals from 26 different healthcare systems across the United States from 1999 to September 2022 was utilized to construct this study. Patients aged 18 years and above were included. Individuals who have been diagnosed with any autoimmune disease have been excluded. A multivariate regression analysis was performed to assess risk of developing microscopic, lymphocytic, and collagenous colitis by accounting for potential confounders including female gender, smoking history, and the use of proton pump inhibitor, nonsteroidal anti-inflammatory drugs, and selective serotonin receptor inhibitors. A two-sided P value <0.05 was considered as statistically significant, and all statistical analyses were performed using R version 4.0.2 (R Foundation for Statistical Computing, Vienna, Austria, 2008).

RESULTS

78,256,749 individuals were screened in the database and 69,315,150 were selected in the final analysis after accounting for inclusion and exclusion criteria. The baseline characteristics of patients with microscopic, lymphocytic, and collagenous colitis is seen in table 1. Using a multivariate regression analysis, the risk of developing microscopic, lymphocytic, and collagenous colitis was calculated and illustrated in table 2.

DISCUSSION

Our study showed that the risk of microscopic colitis, lymphocytic colitis and collagenous colitis was higher in females and smokers. Although medications like SSRI and NSAIDs showed a positive correlation with colitis, the highest likelihood of developing this disease was associated with PPIs. Lansoprazole has been documented to be associated with microscopic colitis as it is believed to inhibit colonic proton pumps, and subsequently promote diarrhea and inflammation. Interestingly, the prevalence of lymphocytic colitis and collagenous colitis was similar in the cohort of patients treated with PPIs, indicating no specific predisposition to either subtype. This study further confirms the risk factors associated with microscopic colitis. It can help guide physicians to recognize and eliminate these risk factors prior to initiating treatment for this disease. Future studies can focus on identifying the incidence of microscopic colitis with the different types of PPIs in the market.

Microscopic Colitis: An Underestimated Disease of Growing Importance

The aim of this paper is to raise awareness of MC as a clinically significant condition and to highlight its under-recognition, risk factors, diagnosis, management, and complications. This paper underlines the diagnostic and therapeutic challenges associated with the often nonspecific symptoms of MC. In order to create this article, we reviewed available articles found in the PubMed database and searched for articles using the Google Scholar platform. Microscopic colitis (MC) is a chronic inflammatory bowel disease, classified into three types: lymphocytic, collagenous, and unspecified. The average age of onset of MC is around 62-65 years and the disease is more common in women than men (nine times more common). The main symptom of MC is watery diarrhoea without blood, other symptoms include defecatory urgency, faecal incontinence, abdominal pain, nocturnal bowel movements, and weight loss. Once considered a rare disease, MC is now being diagnosed with increasing frequency, but diagnosis remains difficult. To date, a number of causative factors for MC have been identified, including smoking, alcohol consumption, medications (including NSAIDs, PPIs, SSRIs, and ICPIs), genetic factors, autoimmune diseases, bile acid malabsorption, obesity, appendicitis, and intestinal dysbiosis. It may be difficult to recognize and should be differentiated from inflammatory bowel diseases (Crohn's disease and ulcerative colitis), irritable bowel syndrome (IBS), coeliac disease, infectious bowel disease, and others. Diagnosis involves biopsy at colonoscopy and histopathological evaluation of the samples. Treatment consists of budesonide oral (the gold standard) or enema. Alternatives include bile acid sequestrants (cholestyramine, colesevelam, and colestipol), biologics (infliximab, adalimumab, and vedolizumab), thiopurines, methotrexate, and rarely, surgery.

Perindopril-Induced Collagenous Colitis: Case Report and Literature Review

We report the first case of collagenous colitis attributed to perindopril use, in a 90-year-old woman. The patient developed diarrhea with hypokalemia, 3 weeks after perindopril was introduced in her medications for uncontrolled hypertension. Significant thickening of the basal epithelial membrane (up to 80 μm) was found on random colon biopsies. Diarrhea resolved within 3 days after perindopril withdrawal. Four months later, left colon biopsies revealed a normalization of the basal membrane thickness. The intrinsic imputability of perindopril as the causative agent of microscopic colitis is considered to be reasonable by the French accountability technique. There was no rechallenge test conducted.

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.

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.

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.

Multidisciplinary Consensus for Rationalizing the Use of Acid Suppressants in Children and Adults: CONFOR

The use of acid suppression therapy (AST) is a common approach for managing a wide spectrum of acid peptic disorders. Histamine type 2-receptor antagonists (H2RAs) and proton pump inhibitors (PPIs) are the most widely prescribed AST in routine clinical practice. However, an exponential surge in the prescriptions of PPIs, such as Omeprazole, Esomeprazole, Pantoprazole, Lansoprazole in recent years and their associated adverse effects have raised concern about their inappropriate and overuse, both in children and adults. To address these issues, a three-step modified Delphi polling process was employed to establish best practice consensus statements for rationalizing the use of acid suppressants. A multidisciplinary expert panel of 13 health professionals across medical specialties, including gastroenterologists, hepatologists, pediatric gastroenterologists, pediatricians, otolaryngologists, cardiologists, nephrologists, gynecologist and orthopedists actively contributed to this collaborative process of consensus development. The expert panel proposed 21 consensus statements providing best practice points on the general use and safety of acid suppressants based on a comprehensive review of scientific literature and clinical expertise. The panel also collaboratively developed a PPI deprescribing algorithm. Altogether, this consensus paper offers evidence-based recommendations and guidance for the rational use of acid suppressants with a blueprint for deprescribing PPIs. This consensus paper contributes to aiding primary care practitioners in improving patient outcomes and minimizing healthcare costs. Additionally, it enhances patient safety and curtail inappropriate usage.

How to cite this article

Prabhoo RY, Pai UA, Wadhwa A, et al. Multidisciplinary Consensus for Rationalizing the Use of Acid Suppressants in Children and Adults: CONFOR. Euroasian J Hepato-Gastroenterol 2024;14(1):99-119.

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.

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.

Endoscopic plication compared to laparoscopic fundoplication in the treatment of gastroesophageal reflux disease: a systematic review and meta-analysis

INTRODUCTION

Endoscopic plication offers an alternative to surgical fundoplication for treatment of gastroesophageal reflux disease (GERD). This systematic review and meta-analysis evaluate outcomes following endoscopic plication compared to laparoscopic fundoplication.

METHODS AND PROCEDURES

Systematic search of MEDLINE, Embase, Scopus, and Web of Science was conducted in September 2022. Study followed PRISMA guidelines. Studies comparing endoscopic plication to laparoscopic fundoplication with n > 5 were included. Primary outcome was PPI cessation, with secondary outcomes including complications, procedure duration, length of stay, change in lower esophageal sphincter (LES) tone, and DeMeester score.

RESULTS

We reviewed 1544 studies, with five included comparing 105 (46.1%) patients receiving endoscopic plication (ENDO) to 123 (53.9%) undergoing laparoscopic fundoplication (LAP). Average patient age was 47.6 years, with those undergoing plication being younger (46.4 ENDO vs 48.5 LAP). BMI (26.6 kg/m² ENDO vs 26.2 kg/m² LAP), and proportion of females (42.9% ENDO vs 37.4% LAP) were similar. Patients undergoing laparoscopic procedures had worse baseline LES pressure (12.8 mmHg ENDO vs 9.0 mmHg LAP) and lower preoperative DeMeester scores (34.6 ENDO vs. 34.1 LAP). The primary outcome demonstrated that 89.2% of patients undergoing laparoscopic fundoplication discontinued PPI compared to 69.4% for those receiving plication. Meta-analysis revealed that plication had significantly reduced odds of PPI discontinuation (OR 0.27, studies = 3, 95% CI 0.12 to 0.64, P = 0.003, I² = 0%). Secondary outcomes demonstrated that odds of complications (OR 1.46, studies = 4, 95% CI 0.34 to 6.32, P = 0.62, I² = 0%), length of stay (MD - 1.37, studies = 3, 95% CI - 3.48 to 0.73, P = 0.20, I² = 94%), and procedure durations were similar (MD 0.78, studies = 3, 95% CI - 39.70 to 41.26, P = 0.97, I² = 98%).

CONCLUSIONS

This is the first meta-analysis comparing endoscopic plication to laparoscopic fundoplication. Results demonstrate greater likelihood of PPI discontinuation with laparoscopic fundoplication with similar post-procedural risk.

Dietary Calcium and Risk of Microscopic Colitis

BACKGROUND

Microscopic colitis (MC) is an increasingly common cause of watery diarrhea particularly in older individuals. The role of diet in MC has received little study.

METHODS

We conducted a case-control study at a single institution enrolling patients referred for elective outpatient colonoscopy for diarrhea. Patients were classified as cases with MC or non-MC controls after a review of colon biopsies by 1 research pathologist. Study subjects were interviewed by a trained telephone interviewer using a validated food frequency questionnaire. Adherent microbes were evaluated from colonic biopsies using 16s rRNA sequencing.

RESULTS

The study population included 106 cases with MC and 215 controls. Compared with controls, the cases were older, better educated, and more likely to be female. Cases with MC had lower body mass index and were more likely to have lost weight. Subjects in the highest quartile of dietary calcium intake had a lower risk of MC compared with those in the lowest quartile (adjusted odds ratio 0.22, 95% confidence interval 0.07-0.76). The findings were not explained by dairy intake, body mass index, or weight loss. We found that dietary calcium intake had significant associations with the abundance of Actinobacteria and Coriobacteriales in the microbial community of colonic biopsies.

DISCUSSION

Compared with patients with diarrhea, cases with MC had a lower intake of dietary calcium. Diet can be associated with alterations in the gut microbiota and with luminal factors that could affect the risk of MC.

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.

Psychiatric medications and the risk of autoimmune and immune-mediated inflammatory diseases: A systematic review and meta-analysis of observational studies

BACKGROUND

Pharmacovigilance reports have suggested that certain commonly used medications may trigger autoimmune diseases (ADs) and immune-mediated inflammatory diseases (IMIDs). We systematically reviewed the literature to evaluate whether psychiatric medication use is associated with ADs and IMIDs.

METHODS

The protocol was registered in PROSPERO (CRD42022296524) before the start of the study. We searched Medline Ovid and Scopus up to November 28th, 2021, for comparative studies, with any psychiatric medication as exposure and ADs and IMIDs as outcomes. Meta-analysis was performed using DerSimonian-Laird random-effects modeling. The PRISMA 2020 guidelines were followed in reporting. Study-level risk of bias was assessed using the Newcastle-Ottawa Scale, and the overall certainty of evidence using GRADE.

RESULTS

There were 7,265 citations from which 31 studies were eligible, all from high-income countries, covering 15 distinct immune diseases. The evidence for the association between selective serotonin reuptake inhibitor (SSRI) use and higher risk of microscopic colitis (meta-OR 2.60, 95% CI 1.05-6.39, I2 97.5%, 6 studies) was of low certainty. A subgroup analysis by the histological type of microscopic colitis showed a statistically significant association only with lymphocytic colitis (meta-OR 2.88, 95% CI 2.60-3.18, I2 00.00%, three studies). In two case-control studies, SSRI use had no significant association with psoriasis (meta-OR 0.80, 95% CI 0.58-1.10, I2 82.4%). The risk of acute pancreatitis was slightly increased with exposure to SSRIs (meta-OR 1.13, 95% CI 1.01-1.26, I2 00.0%), as was the risk of bullous pemphigoid after exposure to antipsychotics (meta-OR 1.79, 95% CI 1.17-2.73, I2 0%).

CONCLUSIONS

We reviewed the literature on whether psychiatric medications associate with the risk of ADs and IMIDs and concluded that, despite several signals, the credibility of evidence remains low at best. Prospective cohort studies would be needed as the next step to confirm the suggestions of increased risk.

Appendectomy and Future Risk of Microscopic Colitis: A Population-Based Case-Control Study in Sweden

BACKGROUND AND AIMS

Microscopic colitis (MC) is an inflammatory bowel disease and a common cause of chronic diarrhea. Appendectomy has been suggested to have immunomodulating effects in the colon, influencing the risk of gastrointestinal disease. The relationship between appendectomy and MC has only been sparsely studied.

METHODS

This was a case-control study based on the nationwide ESPRESSO (Epidemiology Strengthened by histoPathology Reports in Sweden) cohort, consisting of histopathological examinations in Sweden, linked to national registers. Patients with MC were matched to population controls by age, sex, calendar year of biopsy, and county of residence. Data on antecedent appendectomy and comorbidities were retrieved from the Patient Register. Unconditional logistic regression models were conducted presenting odds ratios (ORs) and 95% confidence intervals (CIs) adjusted for country of birth and matching factors. Further subanalyses were made based on MC subtypes (lymphocytic colitis and collagenous colitis), follow-up time postappendectomy and severity of appendicitis.

RESULTS

The study included 14,520 cases of MC and 69,491 controls, among these 7.6% (n = 1103) and 5.1% (n = 3510), respectively, had a previous appendectomy ≥1 year prior to MC or matching date. Patients with a previous appendectomy had an increased risk of MC in total (OR, 1.50; 95% CI, 1.40-1.61) and per the collagenous colitis subtype (OR, 1.67; 95% CI, 1.48-1.88) or lymphocytic colitis subtype (OR, 1.42; 95% CI, 1.30-1.55). The risk remained elevated throughout follow-up, and the highest risk was observed in noncomplicated appendicitis.

CONCLUSIONS

This nationwide case-control study found a modestly increased risk of developing MC following appendectomy.

Microscopic colitis: lymphocytic colitis, collagenous colitis, and beyond

Microscopic colitis (MC) is a chronic inflammatory disease of colon with clinical presentations of chronic, watery, nonbloody diarrhea, and normal or almost normal endoscopic findings. Confirmation of a diagnosis of MC requires microscopic examination on colon biopsy to identify characteristic morphological features, in which 2 main subtypes of MC, lymphocytic colitis (LC) and collagenous colitis (CC), have been described. Although the pathogenesis of MC is still unclear, studies have revealed associations of MC with many risk factors and other diseases such as celiac disease, inflammatory bowel disease, and medication use. Meanwhile, variants of MC, MC incomplete, or MC-like changes in other conditions are still diagnostic dilemmas for pathologists. The goal of this paper is to systemically introduce the clinicopathologic features of MC and focus on unusual features of MC and its associations with other conditions.

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.

Modifiable contributing factors to COVID-19: A comprehensive review

The devastating complications of coronavirus disease 2019 (COVID-19) result from an individual's dysfunctional immune response following the initial severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Multiple toxic stressors and behaviors contribute to underlying immune system dysfunction. SARS-CoV-2 exploits the dysfunctional immune system to trigger a chain of events ultimately leading to COVID-19. The current study identifies eighty immune system dysfunction-enabling toxic stressors and behaviors (hereafter called modifiable contributing factors (CFs)) that also link directly to COVID-19. Each CF is assigned to one of the five categories in the CF taxonomy shown in Section 3.3.: Lifestyle (e.g., diet, substance abuse); Iatrogenic (e.g., drugs, surgery); Biotoxins (e.g., micro-organisms, mycotoxins); Occupational/Environmental (e.g., heavy metals, pesticides); Psychosocial/Socioeconomic (e.g., chronic stress, lower education). The current study shows how each modifiable factor contributes to decreased immune system capability, increased inflammation and coagulation, and increased neural damage and neurodegeneration. It is unclear how real progress can be made in combatting COVID-19 and other similar diseases caused by viral variants without addressing and eliminating these modifiable CFs.

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.

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.

Nonsteroidal anti-inflammatory drug exposure and the risk of microscopic colitis

BACKGROUND

Medication consumption has been suggested as a risk factor for microscopic colitis (MC), but studies of varying design have yielded inconsistent results. Our aim was to evaluate the association between medications and MC.

METHODS

A hybrid cohort of prospectively identified patients undergoing colonoscopy with biopsies for suspicion of MC (N = 144) and patients with MC enrolled within three months of diagnosis into an MC registry (N = 59) were surveyed on medication use. Medication use was compared between patients with and without diagnosis of MC by chi-squared test and binomial logistic regression adjusted for known risk factors of MC: age and gender.

RESULTS

In total, 80 patients with MC (21 new, 59 registry) were enrolled. Patients with MC were more likely to be older (p = 0.03) and female (p = 0.01) compared to those without MC. Aspirin and other non-steroidal anti-inflammatory drugs were more commonly used among patients who developed MC (p < 0.01). After controlling for age and gender, these medications remained independent predictors of MC with odds ratio for any non-steroidal anti-inflammatory drug use of 3.04 (95% CI: 1.65-5.69). No association between MC and other previously implicated medications including proton pump inhibitors and selective serotonin reuptake inhibitors was found.

CONCLUSIONS

In this cohort of patients with chronic diarrhea, we found use of aspirin and non-steroidal anti-inflammatory drugs, but not other implicated medications to be associated with the development of MC. Whether these drugs trigger colonic inflammation in predisposed hosts or worsen diarrhea in undiagnosed patients is unclear. However, we feel that these findings are sufficient to discuss potential non-steroidal anti-inflammatory drug cessation in patients newly diagnosed with MC.

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

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

Diagnosis and Management of Microscopic Colitis in Pediatric Patients

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

The Epidemiology of Microscopic Colitis in Olmsted County, Minnesota: Population-Based Study From 2011 to 2019

BACKGROUND & AIMS

Epidemiologic studies from Europe and North America have reported an increasing incidence of microscopic colitis (MC) in the late 20th century, followed by a plateau. This population-based study assessed recent incidence trends and the overall prevalence of MC over the past decade.

METHODS

Residents of Olmsted County, MN, diagnosed with collagenous colitis (CC) or lymphocytic colitis (LC) between January 1, 2011, and December 31, 2019 were identified using the Rochester Epidemiology Project. Clinical variables were abstracted by chart review. Incidence rates were age- and sex-adjusted to the 2010 US population. Associations between incidence and age, sex, and calendar periods were evaluated using Poisson regression analyses.

RESULTS

A total of 268 incident cases of MC were identified with a median age at diagnosis of 64 years (range, 19-90 y); 207 (77%) were women. The age- and sex-adjusted incidence of MC was 25.8 (95% CI, 22.7-28.9) cases per 100,000 person-years. The incidence of LC was 15.8 (95% CI, 13.4-18.2) and CC was 9.9 (95% CI, 8.1-11.9) per 100,000 person-years. A higher MC incidence was associated with increasing age and female sex (P < .01). There was no significant trend in age- and sex-adjusted incidence rate over the study period (P = .92). On December 31, 2019, the prevalence of MC, LC, and CC (including cases diagnosed before 2011) was 246.2, 146.1, and 100.1 per 100,000 persons, respectively.

CONCLUSIONS

The incidence of MC and its subtypes was stable between 2011 and 2019, but its prevalence was higher than in previous periods. The incidence of MC continues to be associated with increasing age and female sex.

Quantifying risk factors for microscopic colitis: A nationwide, retrospective cohort study

BACKGROUND

Microscopic colitis (MC) is associated with several risk factors; however, their relative risk has been variable and not thoroughly evaluated. We aimed to quantify the risk of medical comorbidities and medications associated with MC and treatment offered to these patients.

METHODS

A population-based retrospective analysis in International Business Machines (IBM) Explorys (1999-2018), a pooled, de-identified database of 63 million patients in the USA, was performed. Odds ratios (OR) were calculated between MC and other diseases/medications. MC patients were also stratified by age to assess trends of MC in different age groups.

RESULTS

A total of 1130 patients had MC in the database. Among medications, non-steroidal anti-inflammatory agents (OR, 20.2) and proton pump inhibitors (OR, 12.1) were associated with highest odds of MC. Among medical comorbidities, infectious gastroenteritis (OR, 26.6) and celiac disease (OR, 22.5) had the highest odds of being associated with MC. Tobacco smoking, psoriasis, Sjogren's syndrome, Clostridium difficile infection, and malabsorption syndromes all conferred odds greater than 10.

CONCLUSION

Early identification of MC is critical for minimizing morbidity and mortality. Epidemiologic information can be integrated with current clinical algorithms to more rapidly identify patients at risk.

Intraepithelial and lamina propria lymphocytes do not correlate with symptoms or exposures in microscopic colitis

Microscopic colitis, a common cause of diarrhea, is characterized by a largely normal appearance of the mucosa but increased numbers of lymphocytes in the epithelium and lamina propria on microscopy. We sought to determine whether T-cell percentage was associated with exposures or symptoms.

Pathogenesis of Microscopic Colitis: A Systematic Review

BACKGROUND

Whereas the exact aetiology of microscopic colitis [MC] remains unknown, a dysregulated immune response to luminal factors or medications is the most accepted pathogenesis hypothesis.

METHODS

We conducted a systematic review of the pathogenesis of MC. We applied the Joanna Briggs Institute methodologies and the PRISMA statement for the reporting of systematic reviews [PROSPERO Trial Identifier: CRD42020145008]. Populations, Exposure of interest, and Outcome [PEO] questions were used to explore the following topics in MC: 1] intestinal luminal factors; 2] autoimmunity; 3] innate immunity; 4] adaptive immunity; 5] extracellular matrix; 6] genetic risk factors; and 7] mechanism of diarrhoea. A search was done in PubMed, Embase, and Web of Science up to February 2020. A narrative description was performed explaining the findings for each aspect of MC aetiopathogenesis.

RESULTS

Thirty-eight documents provided evidence for PEO1, 100 for PEO2, 72 for PEO3 and 4, 38 for PEO5, 20 for PEO6, and 23 for PEO7. The majority of documents were cohorts, case reports, and case series, with a few case-control and some experimental studies. Consistency among data provided by different studies was considered to support pathogenetic hypotheses. MC is a multifactorial disease believed to involve innate and adaptive immune responses to luminal factors, genetic risk, autoimmunity, and extracellular matrix alterations, all contributing by varied mechanisms to watery diarrhoea.

CONCLUSIONS

This is the first systematic review on the aetiology of MC supporting the notion that MC is a multifactorial disease. However, high-profile studies are lacking, and most evidence derives from small heterogeneous studies.

Obesity is associated with decreased risk of microscopic colitis in women

BACKGROUND

Microscopic colitis is a leading cause of diarrhea in the older adults. There is limited information about risk factors. We hypothesized that obesity would be associated with microscopic colitis.

AIM

To examine the association between obesity and microscopic colitis in men and women undergoing colonoscopy.

METHODS

We conducted a case-control study at the University of North Carolina Hospitals. We identified and enrolled men and women referred for elective, outpatient colonoscopy for chronic diarrhea. We excluded patients with a past diagnosis of Crohn’s disease or ulcerative colitis. A research pathologist reviewed biopsies on every patient and classified them as microscopic colitis cases or non-microscopic colitis controls. Patients provided information on body weight, height and exposure to medications via structured interviews or Internet based forms. The analysis included 110 patients with microscopic colitis (cases) and 252 non-microscopic colitis controls. Multivariable analyses were performed using logistic regression to estimate odds ratios and 95% confidence intervals.

RESULTS

Cases were older and more likely than controls to be white race. Study subjects were well educated, but cases were better educated than controls. Cases with microscopic colitis had lower body mass index than controls and reported more weight loss after the onset of diarrhea. Compared to patients who were normal or under-weight, obese (BMI > 30 kg/m²) patients were substantially less likely to have microscopic colitis after adjusting for age and education, adjusted OR (aOR) 0.35, 95% confidence interval (CI) 0.18-0.66). When stratified by sex, the association was limited to obese women, aOR 0.21, 95%CI: 0.10-0.45. Patients with microscopic colitis were more likely to report weight loss after the onset of diarrhea. After stratifying by weight loss, there remained a strong inverse association between obesity and microscopic colitis, aOR 0.33, 95%CI: 0.10 – 1.11 among the patients who did not lose weight. Ever use of birth control pills was associated with lower risk of microscopic colitis after adjusting for age, education and BMI, aOR 0.38, 95%CI: 0.17-0.84.

CONCLUSION

Compared to controls also seen for diarrhea, microscopic colitis cases were less likely to be obese. Mechanisms are unknown but could involve hormonal effects of obesity or the gut microbiome.

Clinical Characteristics and Treatment Response in Microscopic Colitis Based on Age at Diagnosis: A Multicenter Retrospective Study

BACKGROUND

Microscopic colitis (MC) primarily affects older adults; thus, data in younger patients are scarce.

AIMS

To compare clinical characteristics and treatment response by age at diagnosis.

METHODS

This retrospective cohort study was performed at Mayo Clinic and Massachusetts General Hospital. Patients were chosen consecutively using established databases. Patients were 'younger' if age at diagnosis was ≤ 50 years and 'older' if age > 50 years. Treatment outcomes were captured for induction (12 ± 4 weeks), based on the total number of daily stools, and defined as remission (complete resolution), response (≥ 50% improvement), non-response (< 50% improvement), and intolerance. Patients were considered 'responders' if they had remission or response and 'non-responders' if they had non-response or intolerance.

RESULTS

We included 295 patients (52 younger, 243 older). There were no differences in sex, race, MC subtype, and diarrhea severity between groups (all P > 0.05). Younger patients were more likely to have celiac disease (17.3% vs. 5.8%, P = 0.01), while older patients had higher BMI (mean 25.0 vs. 23.8 kg/m², P = 0.04) were more likely smokers (53.9% vs. 34.6%, P = 0.01) and use NSAIDs (48.6% vs. 15.4%, P < 0.01) and statins (22.6% vs. 3.8%, P < 0.01). Overall treatment response was highest for budesonide (88.3%) and did not differ when comparing older to younger patients (90.6% vs. 77.8%, P = 0.12) or by MC subtype (LC, 81.5% vs. CC, 92.9%, P = 0.07).

CONCLUSIONS

There are no significant differences in MC treatment response based on age or disease subtype. These findings support treating patients with MC based on symptom severity rather than age.

Letter: association between medication use and microscopic colitis-selection of controls matters

This article is linked to Sandler et al paper. To view this article, visit https://doi.org/10.1111/apt.16594

Medication use and microscopic colitis

BACKGROUND

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

AIMS

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

METHODS

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

RESULTS

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

CONCLUSION

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

Drug-Induced Colitis

Drug-induced colitis encompasses a wide spectrum of colon disorders that can manifest microscopically or macroscopically. Patients present with new-onset colitis or exacerbations of inflammatory bowel diseases; in some cases, colitis resolves with discontinuation of medication. Mucosal injury can be focal or extensive, involving the entire colonic mucosa, and sometimes involves other parts of the gastrointestinal tract. It has been a challenge to determine the proportion of new-onset colitis caused by medication and there are few data on the overall prevalence. We review the drugs that have been linked with development of drug-induced colitis and strategies for physicians who believe their patients have this disorder-usually discontinuation of the drug believed to cause colitis and treatment with steroids or immune-modulating therapies. Physicians must be aware of medications that can cause colitis.

Proton pump inhibitors long term use-trends and patterns over 15 years of a large health maintenance organization

BACKGROUND

Proton pump inhibitors (PPI) are used for a variety of indications. Despite reported associations with undesirable effects, their long-term use is on the rise, while appropriate indications, dose, and treatment duration may deviate from guideline recommendations.

OBJECTIVES

Primary to examine the annual patterns of PPI use. Secondary- to assess indications for initiating PPI treatment, long-term use, and factors associated with long-term use in a large Israeli health maintenance organization.

METHODS

A historical cohort study of 528 420 eligible PPI users during 2000-2015, analyzed PPI use using defined daily doses and the proportion of patients covered method. Data on indications for treatment initiation, clinical and socio-demographic parameters were captured as well. A multivariable logistic-regression model was used to identify factors associated with long-term use of PPI.

RESULTS

The annual incidence rates of patients initiating PPI treatment were relatively constant, ranging between 2.4% and 3.1% of the adult population, with a monotonic increase in annual consumption and prevalence (reaching 12.7% in 2015). Reflux, functional symptoms, and Helicobacter pylori eradication were the most common indications for initiating PPI therapy. However, 27% of patients had no recorded indication for treatment. Fifteen percent of patients used PPI for over 6 months, especially in older age groups.

CONCLUSIONS

Utilization of PPI increases steadily, mainly due to chronic use. Prolonged consumption is associated with specific clinical indications and older age. Health organizations should encourage awareness of appropriate use among physicians, specifically in the elderly, patients with reflux, and those with functional disorders.

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.

Incidence of collagenous colitis in NHS Lothian: a population-based study

OBJECTIVE

Increases in incidence of collagenous colitis (CC) have been documented across Europe; however, previous data from NHS Lothian (1998-2003) demonstrated this to be a low-prevalence area. We aimed to assess incidence of CC in NHS Lothian over time by comparing a more recent cohort (2013-2018) with our existing cohort.

METHODS

All histologically confirmed diagnoses of CC between 2013 and 2018 were obtained from the NHS Lothian colorectal pathology department (Western General Hospital, Edinburgh). Case record review was performed to obtain relevant demographic and clinical data. Data were also collected regarding the availability of colonoscopy in NHS Lothian.

RESULTS

224 cases of CC were diagnosed between 2013 and 2018, compared with 25 between 1998 and 2003. Mean annual incidence rose from 0.5/100 000 population to 4.3/100 000 population. Incidence in females ≥60 years old rose from 2.3/100 000 population to 22.4/100 000 population (p<0.001). The total number of colonoscopies performed increased by 179.1% from 15 262 (1998-2003) to 42 600 (2013-2018), with the number of CC cases per 1000 colonoscopies performed rising from 1.7 to 5.3 (p<0.001).

CONCLUSION

We describe the increasing incidence of CC in Southeast Scotland, with temporal trends comparable to other European countries. The increase is particularly marked in older females and parallels increasing numbers of colonoscopies being performed.

Medication use and microscopic colitis: a multicentre retrospective cohort study

BACKGROUND

Medication use has been implicated in the development of microscopic colitis (MC). However, studies have demonstrated inconsistent findings and there exist variations in design.

AIM

To measure the association between medication use and MC.

METHODS

Patients who underwent a colonoscopy over a 10-year period at two academic medical centres (Columbia University Medical Centre and Mayo Clinic) were identified. Cases were patients with biopsy-proven MC and controls were patients who underwent colonoscopy for evaluation of diarrhoea with biopsies negative for MC. Cases were matched by age, gender and calendar period with up to two controls. Demographics, medication use, smoking history and coeliac disease status were collected. Conditional logistic regression was used with and without adjustment for smoking.

RESULTS

A total of 344 patients with MC were matched to 668 controls. After adjusting for smoking, there was an inverse association between MC and use of proton pump inhibitors (PPIs) (OR 0.64; 95% CI 0.47-0.87), H2 blockers (OR 0.46; 95% CI 0.24-0.88) and oral diabetes medications (OR 0.47; 95% CI 0.27-0.81). There was a positive association with nonsteroidal anti-inflammatory drug (NSAID) use and MC (OR 1.63; 95% CI 1.12-2.38).

CONCLUSIONS

NSAID use was associated with MC, while use of PPIs, H2 blockers and oral diabetes medications were inversely related to MC. Our use of a control group with diarrhoea, as opposed to healthy controls, may have contributed to these inverse associations. Future studies of drug-induced microscopic colitis should include control groups with diarrhoea, and not only healthy controls.

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.

Gastrointestinal Infection and Risk of Microscopic Colitis: A Nationwide Case-Control Study in Sweden

BACKGROUND AND AIMS

Gastrointestinal infections have been linked to changes in the composition and function of gut microbiome and development of inflammatory bowel diseases. We therefore sought to examine the relationship between gastroenteritis and risk of microscopic colitis (MC).

METHODS

We conducted a case-control study of all adult patients with MC diagnosed between 1990 and 2016 in Sweden matched to up to 5 general population controls according to age, sex, calendar year, and county. Cases of MC were identified using Systematized Nomenclature of Medicine codes from the ESPRESSO (Epidemiology Strengthened by histoPathology Reports in Sweden) study, a cohort of gastrointestinal pathology reports from all 28 pathology centers in Sweden. We used logistic regression modeling to estimate adjusted odds ratios (aORs) and 95% confidence intervals (CIs).

RESULTS

Through December of 2016, we matched 13,468 MC cases to 64,479 controls. The prevalence of previous diagnosed gastrointestinal infection was 7.5% among patients with MC, which was significantly higher than in controls (3.0%, P_comparison < .001). After adjustment, gastroenteritis was associated with an increased risk of MC (aOR 2.63; 95% CI 2.42-2.85). Among specific pathogens, Clostridioides difficile (aOR 4.39; 95% CI 3.42-5.63), Norovirus (aOR 2.87; 95% CI 1.66-4.87), and Escherichia species (aOR 3.82; 95% CI 1.22-11.58), but not Salmonella species, were associated with an increased risk of MC. The association between gastrointestinal infections and risk of MC was stronger for collagenous subtype (aOR 3.23; 95% CI 2.81-3.70) as compared with lymphocytic colitis (aOR 2.51; 95% CI 2.28-2.76; P_{heterogeneity} = .005). The associations remained significant after adjustment for immune-mediated conditions and polypharmacy and when compared with unaffected siblings.

CONCLUSION

In a nationwide study, we found that gastrointestinal infection, particularly Clostridioides difficile, is associated with an increased risk of subsequent MC. This study was approved by the Regional Ethics Committee, Stockholm, Sweden (Protocol no. 2014/1287-31/4).

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.

Association between use of proton pump inhibitors and colorectal cancer: A nationwide population-based study

BACKGROUND

Proton pump inhibitors (PPIs) use is associated with hypergastrinemia and gut microbiota alteration. Concern over the risk that these factors may increase chances of colorectal cancer (CRC) has risen. To investigate the association between PPIs use and CRC using a large population-based cohort and examine whether the PPIs may differ regarding the risk of CRC.

METHODS

We conducted a nationwide cohort study using a database from Taiwan National Health Insurance followed up longitudinally from 1999 through 2011. Patients with PPIs use were compared with non-use controls at a 1:1 ratio, for age, sex, comorbidities, and medications. We performed Cox proportional-hazards regression analysis to estimate the association between PPIs use and the development of CRC.

RESULTS

Among the 45382 eligible PPIs users, 172 (0.4%) developed CRC during a median follow-up of 5.4 years. PPIs use was associated with a higher risk of CRC with an adjusted HR of 2.03 (95% CI 1.56-2.63, P<0.001). The risk increased with more frequent use of PPIs (HR 1.59, 95% CI 1.19-2.14; 2.59, 95% CI 1.84-3.65 and 4.33, 95% CI 2.75-6.80 for ≤30 cDDD per year, 30-90 cDDD per year, and ≥90 cDDD per year, respectively). There was also a statistically significant trend toward an increased risk with long-term PPIs use for more than one year. All PPIs, except pantoprazole and rabeprazole, were associated with an increased risk of CRC.

CONCLUSIONS

The present study suggests that PPIs use might increase the risk of CRC in a dose-dependent manner.

Case Report: Ramipril and microscopic colitis; a necessary tool of cardiologists can rarely be devastating for patients

Angiotensin converting enzyme inhibitors could lead to severe diarrhoea related to microscopic colitis. Few of such cases have been reported before and this serious problem, from a widely used class of drugs in hypertension and heart failure, needs to be more recognised. We describe the case of collagenous colitis related to ramipril use in the following case report.

A 74-year-old farmer who had a history of triple vessel coronary artery disease was admitted to district general hospital with non-ST elevation myocardial infarction. He had known alcohol-related chronic pancreatitis with chronic diarrhoea as a complication, which was managed with pancreatic enzyme replacement therapy. However, he developed severe worsening of diarrhoea causing bowel incontinence and nocturnal symptoms during his admission to hospital. The explosive and watery nature of diarrhoea with urgency was so troublesome that it delayed coronary revascularisation and lead him to have significant psychological distress and low mood while nocturnal bowel motions meant he was unable to sleep. He was compliant with his pancreatic enzyme replacement therapy during this period. Infective causes were ruled out by stool microbiology examination and coeliac disease by oesophagogastroscopy and biopsy. It was noticed that he was recently prescribed ramipril that was later stopped as a possible diarrhoea trigger. Diarrhoea started settling immediately and resolved to his baseline within a week. A colonoscopy was performed in the meantime and biopsies demonstrated microscopic colitis (MC). He did not tolerate budesonide well so was stopped. However, a follow-up colonoscopy with biopsy in two months showed resolution of MC.

Latest insights into the hot question of proton pump inhibitor safety - a narrative review

Proton pump inhibitors (PPIs) are among the most widely prescribed medications worldwide and their use is continuously increasing. Although they have been shown to combine high therapeutic efficacy and good safety profile in many studies, in last years we have witnessed the publication of many articles reporting the possible association of long-term PPI therapy with important unexpected adverse events and these observations have created alarmism in both patients and physicians. However, the majority of these studies are observational, retrospective and prone to residual confounding. Also, the odds ratio values are generally comprised between 1 and 2 and therefore devoid of strong clinical relevance. As it is unlikely that prospective randomized trials will be ever done to reinforce these associations, we can only attempt to distinguish clear- from unclear-defined adverse events from the available literature. Nowadays we can reasonably exclude cardiovascular diseases, community-acquired pneumonia, all-cause mortality, dementia and bone fractures from PPI-related adverse events. However, physicians should be aware of the existence of possible risks when treating their patients, especially the elderly and frail ones, with long-term PPIs, which should be prescribed only to persons with defined indications and at lowest dose and duration.

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.

The association between smoking and both types of microscopic colitis: A systematic review and meta-analysis

BACKGROUND AND STUDY AIMS

It has been suggested that smoking may be associated with microscopic colitis (MC) in some studies; however, there are conflicting results in the current literature with many of these studies having significant limitations. Our study aims to offer a meta-analysis evaluating the association between MC, including both its subtypes, and smoking.

PATIENTS AND METHODS

A systemic review was conducted in PUBMED, Embase, PubMed Central, and ScienceDirect databases from inception through December 2019. Effect estimates from the individual studies were extracted and combined using the random effect, generic inverse variance method of DerSimonian and Laird and a pooled odds ratio (OR) was calculated. Forest plots were generated, and publication bias was assessed for using conventional techniques.

RESULTS

Eight observation studies with a total of 1461 patients with MC were included in this study, 383 of whom were active smokers (26.2%). Current smoking was significantly associated with MC (OR 3.58, 95% CI, 2.51-5.11), lymphocytic colitis (LC) (OR 3.64, 95% CI, 2.46-5.38), and collagenous colitis (CC) (OR 4.43, 95% CI, 2.68-7.32). Gender-specific subgroup analysis showed a significant association with smoking was found for CC in men (OR 4.53, 95% CI, 1.59-12.85), CC in women (OR 3.27, 95% CI, 2.35-4.54), LC in women (OR 2.27, 95% CI, 1.27-4.06) and MC in women (OR 2.93, 95% CI, 2.09-4.10). We found no publication bias as assessed by the funnel plots and Egger's regression asymmetry test.

CONCLUSION

Our meta-analysis found a statistically significant association between smoking and both subtypes of MC.

Microscopic colitis and its associations with complications observed in classic inflammatory bowel disease: a systematic review

Objectives: Crohn's disease and ulcerative colitis are associated with an increased risk to develop anemia, cutaneous diseases, liver diseases, malignancy, osteoporosis, rheumatic diseases, thromboembolism and uveitis. The association between these diseases and microscopic colitis (MC) is not known. The aim of the present systematic review was to examine associations between MC and diseases observed in association with Crohn's disease and ulcerative colitis.Material and methods: According to the review protocol, original articles which described the prevalence of abovementioned diseases in relation to MC, were searched for in PubMed, Embase and Web of Science.Results: After exclusion of duplicates, 928 articles remained. Based on relevancy of their title, abstract or type of article, 16 articles were ordered in full text and after assessment, nine articles could be included in the review. A second research strategy with individual diseases rendered further two articles. Seven articles covered malignancy/neoplasia, where four showed no association with malignancy and three a reduced association compared with controls. Four articles covering rheumatic diseases showed an association between these diseases and MC. One study showed an association between MC and osteoporosis, whereas one did not. One study showed an association between MC and cutaneous diseases, whereas anemia, eye diseases and thromboembolism showed no associations.Conclusions: Due to short follow-up time in small studies, with selection bias due to exclusion of former or prevalent malignancy in an older population, no conclusions can be drawn concerning the true association between MC and malignancy. Rheumatic diseases seem to be associated with MC.