Percutaneous nephrolithotomy for a partial staghorn calculus in a renal allograft following simultaneous pancreas-kidney transplantation.

Urolithiasis in renal allografts is rare, but large or complex stones present unique surgical challenges due to altered pelvic anatomy and proximity to vascular and visceral structures. Percutaneous nephrolithotomy (PCNL) is the gold-standard treatment for staghorn calculi but is technically demanding in transplanted kidneys. This complexity is amplified in recipients of simultaneous pancreas-kidney (SPK) transplants, where both grafts drain into the bladder. We describe a man in his 40s with type 1 diabetes and end-stage renal disease who underwent SPK transplantation in 2018. He presented with intermittent haematuria, and imaging demonstrated an 18 mm partial staghorn calculus in the transplanted kidney located in the left iliac fossa. Antegrade access was obtained under fluoroscopic guidance, and the stone was fragmented. Stone fragments were extracted, achieving complete clearance. This case highlights the potential value of tailored access planning, image guidance and multidisciplinary involvement when considering stone clearance in anatomically complex transplant recipients.