Review
English
Fathi O. Dakhil
Department of Medicine, Faculty of Medicine, El Arab Medical University, Benghazi, Libya
JMJ Vo1. 8 No.4 (Winter) 2008:239-246
Abstract
Microscopic colitis, encompassing collagenous and lymphocytic colitis, is now considered a fairly common cause of chronic watery diarrhoea, especially in elderly women. It is becoming more frequently diagnosed. The aetiology of this disease is still unknown. Collagenous colitis is characterised by a thick subepithelial band of collagen (CB); (CC > 10 µm : normal < 3 µm). The estimated incidence varies in different reports, from 0.6 to 2.3 cases/100,000 inhabitants. A prevalence of 15.7 cases/100,000 inhabitants has been reported. The aetiology of the disease is as yet undetermined; four potential mechanisms for collagen deposition are suggested: firstly; an inflammatory condition or injury, secondly; plasmatic vasculosis, thirdly; pericryptal-subepithelial myofibroblast sheath dysfunction, and finally; reduced degradation and pathological accumulation of matrix components. Both the endoscopic and radiological appearances are usually normal and the majority of laboratory analyses are unhelpful. The diagnosis relies on recognition of the widened subepithelial collagenous band by an alert histopathologist. There is an association with autoimmune diseases such as coeliac disease, connective tissue diseases and thyroid disorders. Currently treatment with either oral or rectal budesonide seems the most efficacious medication. The natural history appears to be benign in most reported cases, and tends to follow a variable course, waxing and waning and often resolving either spontaneously or with treatment. The diagnosis should be considered in any patient especially in the elderly population presenting with watery nonbloody diarrhea. Keywords: Coeliac disease, Colitis, Collagenous colitis, Diarrhoeal diseases, Lymphocytic colitis, Microscopic colitis Link/DOI: http://www.jmj.org.ly/PDF/winter2008/239.pdf