Polyps of the rectosigmoid colon are common complications of intestinal schistosomiasis and found present in 17–20 per cent of our cases. Schistosomiasis was found present in 26.5 per cent of our series of autopsy cases of persons over 5 years of age.
Patients with polyp formation of the rectosigmoid colon associated with schistosomiasis, ranged from 19–40 years of age, and presented complaints referable to the rectum and colon. The most frequent symptoms in our series were rectal bleeding and tenesmus.
Clinical and autopsy studies indicated that the polyps are primarily limited to the rectosigmoid portion of the bowel.
The gross and microscopic findings have been described in detail.
The majority (74.8%) of the 159 polyps contained eggs of the mansoni type whereas 30.2 per cent contained the S. haematobium type.
The combination of S. mansoni and S. haematobium was present in 17.6 per cent of the polyps. Worms were found in less than 2 per cent of the polyps.
Studies in regard to pathogenesis, mucosal changes, and relationship to neoplasia are in progress and are to be reported in the future.