Bilateral ureteral endometriosis with end-stage renal failure.

Only 16 cases of bilateral ureteral endometriosis have been reported to date. A contiguous spread of the disease is generally thought to be the mechanism of ureteral involvement. We report a case in which the left ureter contains both intrinsic and separated extrinsic forms and the right one an extrinsic form of endometriosis, giving us the opportunity to discuss the different pathogenetic mechanisms and to suggest that dissemination of endometriosis by lymphatic pathways is the most probable explanation.