Microscopic Colitis

Abstract

Microscopic colitis (MC) is the common denominator for lymphocytic and collagenous colitis (CC). It is now recognized as a relatively frequent cause of diarrhea that equals the prevalence of inflammatory bowel disease. Patients are typically middle-aged women, but disease may occur at every age. Patients with MC report watery, non-bloody diarrhea in the absence of endoscopic and radiologic abnormalities. Lymphocytic colitis is characterized by an increased number of intraepithelial lymphocytes, and CC by a thickened subepithelial collagen band, whereas in both an increased mononuclear infiltration of the lamina propria is found. The pathogenesis of MC is largely unknown, but may relate to autoimmunity, adverse reactions to drugs or (bacterial) toxins, and abnormal collagen metabolism in the case of CC. Budesonide is so far the only drug that has proven efficacy in randomized controlled trials both for the induction and maintenance of remission. Patients who are nonresponsive, dependent or who experience side effects on budesonide may benefit from thiopurine or anti-TNF treatment, but these options are still experimental. The long-term prognosis of MC is good; it does not appear to predispose to malignancies and can in some cases be self-limiting. Further research and randomized clinical trials are required to expand our understanding of the natural course and the pathogenesis of MC.

Automated image analysis in the study of collagenous colitis

“… 6 , 14 The pathogenesis of MC is largely unknown although it seems likely that MC is a multifactorial disease. 2 , 15 The histopathology is of crucial importance in diagnostics, and it is therefore mandatory that the criteria are reliable and reproducible.…”

Diagnostic Algorithm and Treatment for Microscopic Colitis: A Review.

“…This study also suggested that bismuth might be most effective in patients with milder degrees of diarrhea (Gentile et al 2015). Although based on these limited data, the use of bismuth appears to be effective and well tolerated (Bouma and Münch 2015). The use of bismuth in Western Europe is limited because it is not regularly available (Bouma and Münch 2015).…”

“…The etiology of MC is unknown, and studies to solve disease pathogenesis are still in their beginning (Park 2015) (Bouma and Münch 2015). The pathophysiology of MC is still unknown, but there is strong evidence that MC is frequently associated with the use of certain medications and certain systemic disorders (such as autoimmune diseases) (Storr 2013).…”

“…Although based on these limited data, the use of bismuth appears to be effective and well tolerated (Bouma and Münch 2015). The use of bismuth in Western Europe is limited because it is not regularly available (Bouma and Münch 2015). For these reasons, the AGA has conditionally recommended bismuth salicylate as a second-line alternative treatment that may be appropriate for select patients who have contraindications to corticosteroids or for whom cost is a determining factor (Nguyen et al 2016).…”

Microscopic colitis—microbiome, barrier function and associated diseases

“…In these cases discontinuation of the medication is the easiest; however not always sufficient solution to treat the MC. Although the primary response to budesonide is often good, with response rate of around 80% (14), relapses occur often (60-80%) when the treatment is stopped (9,18). Besides the relapses, patients in remission can still suffer from persisting symptoms such as abdominal pain, fatigue, arthralgia or myalgia several years after diagnosis (9).…”