Abstract: In Crohn’rs disease specific clinical and pathological findings are often lacking,and it is easy to make a wrong diagnosis.This paper deals with a retrospective study of fifty cases seen during the period of 1958 to 1980.The diagnosis of this series of patents had been mistaken in 92%.On the basis of an analysis of the clinical pathological findings,the disease was classified into the following clinical and pathological patterns, hoping that it would be helpful in reaching a correct diagnosis.
（1）Ulcerative colitis pattern:There were four patients of this pattern,in whom the distal ileum and ascending colon were involved,significant symptoms included diarrhea, usually with blood and pus cells in the stools,bleeding and fever.
（2）Intestinal tuberculosis pattern:There were ten patients in this pattern.The small intestine was the main site of involvement,and in only one the lesion was localized to ascending colon.In all these ten cases the lumen of the bowel was markly narrowed,but narrowing was usually localized to a single segment.The involved small bowels were encircled by“fingers”of mesenteric fat.Cardinal symptoms of this pattern were low fever,anorexia,loss of weight and diarrhea alternation with constipation.
（3）Colonic carcinoma pattern:Six patients showed this pattern,with involvement of ileocecal junction,cecum,decending colon,and transverse colon.Enlargement of ruesenteric nodes,marked thickening of the bowel wall,and extension of mesenteric fat around the involved bowel were the chief pathological findings.Fibrosis in these structures produces irregular masses in various sizes.
（4）Intestinal ohstruction pattern:There were eleven patients in this pattern.The lesion was mainly located in the distal ileum,with clinical symptoms and signs of intestinal obstruction.
（5）Complication pattern:Massive bleeding,perforation,and fistula were the major complications in this pattern, Among 50 cases,death occurred in four patients because of serious complications.