A Leak Beneath the Graft: Description of a Rare Ureteral Injury Following Aortobifemoral Bypass.

Ureteral injury is an uncommon but clinically significant complication of major vascular surgery, including aortobifemoral bypass, due to the close anatomic relationship between the ureters and the aortoiliac vessels. Delayed diagnosis may lead to urinoma formation, urinary obstruction, infection, and contamination of prosthetic vascular grafts; however, clinical presentation is often nonspecific and may resemble more common postoperative vascular complications. We report a 59-year-old man who underwent elective aortobifemoral bypass with Dacron graft placement and presented two weeks later with progressive left lower quadrant pain radiating to the flank and testicle. Contrast-enhanced computed tomography angiography demonstrated a rim-enhancing retroperitoneal fluid collection encasing the vascular graft with mild hydronephrosis, and delayed-phase CT urography confirmed contrast extravasation from the left ureter, consistent with urinoma due to ureteral injury. Management consisted of multidisciplinary consultation, urinary diversion via percutaneous nephrostomy, avoidance of direct drainage due to graft proximity, and intravenous antibiotic therapy. The patient remained clinically stable with preserved renal function, imaging demonstrated resolution of the urinoma, and a ureteral stent was placed to facilitate healing. This case highlights the importance of considering ureteral injury after vascular bypass surgery and underscores the diagnostic value of delayed-phase CT urography, as early recognition and coordinated multidisciplinary management are essential to prevent renal and graft-related complications.