<prompt> Dermatological manifest of IBD:Pyoderma gangrenosumNecrolytic migratory erythemaImpetigoPsoriasis  <response>: Ans. a Pyoderma gangrenosumRef: Sabiston 20th edition, Page 1341 Skin manifests in ulcerative colitis: Most common erythema nodosum In 10-15 cases Pyoderma gangrenosum Most common site pretibial region--erythematous plaque 