Schistosomiasis is a chronic granulomatous inflammation that affects many systems in the body including the gastrointestinal tract. Appendiceal schistosomiasis is also described and can be a precursor lesion of schistosomal appendicitis. The present study was done to make a retrospective analysis of histopathological changes in the gastrointestinal tract affected by Schistosoma mansoni among patients attending Sohag University Hospital, Sohag Governorate between June 2013 and June 2016. A total of 150 colon and 30 appendix specimens were collected through out the period from male infected patients aged between 35-50 years and suffering from abdominal pain and dysentery. Histopathological examination of the tissue biopsies was performed. 5μ tissue sections were prepared and examined microscopically. Ten specimens were documented to have intestinal schistosomiasis, nine of the colon 9/150 (6%) were diagnosed as chronic schistosomal colitis and one of the appendix 1/30 (3.3%) as chronic schistosomal appendicitis. Microphotographs of the tissue sections were prepared for histopathological observations. Histopathological examination of all specimens revealed degenerated pinkish and calcified bluish bilharzial eggs in the submucosa and even musculosa with surrounding granulomatous reaction. Bilharzial polyps of the colon were detected in two specimens (20%) and bilharzial worms within venules of the muscle layer in two specimens (20%). During the present study, S. mansoni
was documented as a not uncommon cause of chronic colitis and for the first time from Sohag as a cause of chronic appendicitis. All specimens did not show any malignant or premalignant cells