Ultrasound evaluation of uncommon renal transplant complications.

Twenty-five patients who had undergone renal transplants developed uncommon complications that were detected and followed serially with sonography. Two patients developed renal calculi, which produced hydronephrosis in both instances. Other uncommon causes of postoperative hydronephrosis occurred in 5 cases; the causes included ureteral necrosis, ureteral stricture, and a renocutaneous fistula. Eight cases of renal infarction, manifesting 3 different sonographic appearances, were encountered. The presence and disappearance of postoperative gas in the collecting system were documented in 3 patients. The other unusual abnormalities detected involving the transplanted kidney include tuberculosis, pyonephrosis, 3 solitary cysts, a corpus lutem cyst simulating a perinephric fluid collection, and massive urinary ascites.