Schistosomal polyposis of the urinary bladder.

Anatomic, clinical, and digestion analyses were done on 18 human urinary bladder polyps from patients with Schistosoma haematobium infections. Variations in histologic pattern conformed to stages in progression of the disease; most were from active cases with significant egg burdens. The data suggest that polypoid lesions of active schistosomiasis may persist as polyps in the inactive stage if antecedent active infection was heavy.