Avulsion of Ureteropelvic Junction

Although microscopic hematuria was discovered on the initial trauma work up, there was no episode of hypotension. The abdominal CT demonstrated prompt bilateral nephrograms with only minimal perirenal fluid(figure 1). A diagnosis of renal contusion was made, and no further evaluation was deemed necessary. The patient subsequently developed a large urinoma with failure of opacification of the right ureter on contrast CT (figure 2). In retrospect, the initial CT would likely have identified the injury if delayed views had been taken to better document the collection system.

The patient underwent cystoscopy for retrograde evaluation of the extent of ureteral injury. Contrast did not pass beyond the level of the ureteropelvic junction (UPJ). This was thought to be consistent with avulsion of the UPJ. Because the injury was almost two weeks old, and the patient was febrile, it was decided to drain the urinoma percutaneously, and treat with iv antibiotics for several days. Subsequent exploration revealed a dense inflammatory mass surrounding the right lower renal pole with complete disruption of the UPJ. The renal pelvis was inflamed and atrophic, and not felt to be suitable for reanastomosis. Thus, the inferior renal pole was opened, and a ureterocalycostomy performed without complications. A nephrostomy tube and ureteral stent were left in place for drainage.

Although commonly seen in the pediatric population where the kidney is more mobile within the retroperitoneum, complete disruption of the UPJ is rare in adults. Had the injury been identified immediately, primary reanastomosis would have been the optimal repair.