MICROSCOPIC COLITIS ByOmar Mohammed Saleh Assistant Lecturer of Tropical Medicine and Gastroenterology- HUCOM-2015.
Objectives: Definition Epidemiology EtiologyPathophysiology DiagnosisTreatment Complications and Prognosis
Diarrhea:Diarrhea is defined in adults by abnormal stool weight (>200 g/day), consistency (loose or liquid), and/or frequency (>3 times/day). A 4-week symptom duration is generally considered as a cutoff point to distinguish acute (4 weeks) diarrhea.
Definition:Microscopic colitis is a clinical syndrome of unknown etiology, characterized by chronic watery diarrhea in the absence of macroscopic changes in the large bowel. Ianiro G, et al. Microscopic colitis. WJG. 2012. Types :Lymphocytic colitis Collagenous colitis Incomplete MCMC not otherwise specified Paucicellular LC MC with giant cellsPseudomembranous CCMC with granulomatous inflammationCryptal LC
Epidemiology:Is it a missed disease ? OR Under diagnosed illness !!
Risk factors:Female gender Older age Concomitant autoimmune diseases Solid organ transplantation
Etiology:Multifactorial Idiopathic Autoimmune phenomena; 30-50 % of MC have autoimmune diseases Drugs Familial Possible enteric infections or toxinsSmoking
Review of the literature, modified from Beaugerie and Pradi
Drug- induced microscopic colitis Low likelihoodIntermediate likelihood Highly likelihood CimetidineGold saltspiasciedineCarbamazepineCelecoxibDuloxetineFluvastatinFlutamideOxetoroneMadoparParoxetineSimvastatinstalevoAcarbose Aspirin and NSAIDsClozapine EntocaponeFlavonoidLansoprazoleOmeprazole/esomeprazoleRanitidineSertralineticlopidine
Pathogenesis: Still not clearly understood !Genetic; family cluster, diseases with strong genetic component Infectious element , chronic inflammation Bile salts; increased malabsorption, response to bile acid binding agents Abnormal immune response to luminal antigens.> cytotoxic tissue damage In CC, dysfunction of subepithelial myofibroblast excessive Collagen deposition mechanical diffusion barrier
Diagnosis:Clinical presentation: Chronic watery diarrhea Abdominal pain Weight lossFecal incontinence
Histopathological examination of the taken biopsy is the golden tool for making diagnosis
Lymphocytic colitis Collagenous colitis 1-Intraepithelial lymphocytosis (20IEL per 100 surface epithelial cells
2-Inflammation in the lamina propria consisting of mainly lymphocytes and plasma cells3-Epithelial damage, such as flattening and detachment4-Subepithelial collagen layer not present or less than