A histological and kinetic study of an ileal conduit.

Abstract Ileal mucosa used as a urinary bladder for a 9-month period has been studied in a patient with limited life expectancy. Several biopsies removed at intervals up to 48 hr after tritiated thymidine injection revealed a mucosa in various stages of atrophy characterized early by a reduction in villus number and size, and later by a decrease in the number of crypts. A labeled mitosis curve revealed an S phase of approximately 20 hr and a G 1 of greater than 21 hr. The replacement time for this mucosa based on the labeled index at 1 hr and the mitotic index was estimated to be between 10 and 15 days. Histological and kinetic similarities of this tissue to normal human colon were noted and the patchy atrophy contrasted with the conditions of atrophic small bowel.