A Case Report of Left Pyelonephritis With Low‐Grade Contralateral Vesicoureteral Reflux After Robot‐Assisted Right Nephroureterectomy

ABSTRACT Introduction Pyelonephritis with contralateral vesicoureteral reflux (VUR) after robot‐assisted radical nephroureterectomy (RANU) in a solitary kidney has rarely been reported. Case Presentation A 73‐year‐old woman with preoperative lower urinary tract symptoms (LUTS; IPSS 15, OABSS 7) underwent right RANU for urothelial carcinoma of the renal pelvis (cT3N0M0). On postoperative day (POD) 12 she developed fever, and on POD 16 she was readmitted with left pyelonephritis and Escherichia coli bacteremia. Contrast‐enhanced computed tomography revealed multiple wedge‐shaped hypoenhancing areas in the left kidney, consistent with acute focal bacterial nephritis. Inflammatory markers improved promptly with antibiotics. Cystography on POD 21 demonstrated left grade 1 VUR limited to the storage phase, which resolved spontaneously 1 month after discharge. Conclusion Latent lower urinary tract dysfunction may unmask contralateral VUR in patients with a solitary kidney after RANU. Preoperative LUTS evaluation and prompt cystography during postoperative infection may help preserve contralateral renal function.