Endoscopic combined intrarenal surgery for complex ureteral lithiasis in a renal allograft: A case report.

Ureteral lithiasis in renal allografts can quickly compromise graft function, particularly as the transplant kidney often serves as a solitary functioning unit. A 45-year-old male renal allograft recipient presented with acute graft dysfunction four years post-transplantation, with imaging revealing a 5-mm proximal ureteral stone and hydronephrosis. Retrograde ureteroscopic access and stent placement failed due to severe ureteral tortuosity. The procedure was converted to endoscopic combined intrarenal surgery(ECIRS), successfully removing the stone via a rendezvous-assisted approach. Postoperative outcomes were favorable, with improved serum creatinine and stable graft function at six months, demonstrating ECIRS as a salvage approach when retrograde methods fail.