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What is True about Crohn&;s disease - and explain in detail?
Ans. is 'b' i.e., Sinus & fistula Features Ulcerative coliits Crohn's ds o Rectal involvement o Distribution of lesions o Mucosal appearance o Associated ileal* o Perianal abscess, fistulas o intestinal strictures & obstruction o Intestinal fistulas o Fissures (Radiological) o Toxic megacolon* o Extraintestinai Manifestation - * Sclerosing pericholangitis * Uveitis & Arbritis * Pyoderma gangrenosum >90%* Continuous* Friable, diffusely involved 10%, mild, terminal ileal inflammation Rare Not seen Not seen Not seen Rare but more than crohns ds Common* Common* Common Rectum spared in > 50% Skip lesions* Cobblestone* Appearance 50% have combined ilead and colonic involvement Common Common Common Common Very rare Rare Common* Rare Pathological Features o Depth of inflammation o Creeping mesentric fat o Fibrous thickening of wall o Pseudopolyps o Granulomas o Dysplasia o Carcinoma Mucosal* Not seen Not seen Common* Not seen Common* 10%* Transmural* Common* Common (lead pipe)* Rare Common* Rare Rare o Stud ulcers or Collar studbutton ulcers are seen in ulcerative colitis.