[Bilateral ureteral obstruction by periarterial fibrotic reactions in aortoiliac arteriosclerosis: report of a case].

A 60-year-old man visited our hospital with the chief complaint of right flank pain. A right ureteral stone was suspected by the findings of KUB and DIP, and conservative treatment was carried out. Repeat KUB and DIP a month after treatment showed that the stone shadow was not visible and right hydronephrosis had increased. Closer examinations by RP and CT scan revealed right ureteral obstruction caused by periarterial fibrosis accompanied with arteriosclerotic changes of the aortoiliac region. The arteriosclerotic changes were confirmed by pelvic arteriography, and then right ureterolysis and lateral displacement were performed. DIP four months after the operation showed improvement of right hydronephrosis, but left hydronephrosis was observed. As the same cause as the right side was suspected, left ureterolysis and intraperitoneal transposition were also performed. Histological findings of each periureteral tissue resembled idiopathic retroperitoneal fibrosis. DIP three months after the second operation showed no hydronephrosis. Case reports of ureteral obstruction due to perianeurysmal fibrosis have not been infrequent recently, but our case showed severe arteriosclerotic changes instead of conspicuous aneurysm. The possibility of occurrence of periarterial fibrosis caused by severe arteriosclerotic changes is discussed.