Retrograde intrarenal surgery for a staghorn renal calculus in a patient with solitary kidney and urinary tract deformity: a case report

Staghorn renal calculi are large, branched stones in the kidney that partially or completely fill the renal pelvis and renal calyces. Percutaneous nephrolithotomy (PCNL) is the gold standard treatment for staghorn calculi. However, we report a retrograde intrarenal surgery (RIRS) performed to treat a staghorn calculus in a patient with a solitary kidney and a deformed urinary tract. The 37-year-old male patient presented with right-sided lumbar pain. The computed tomography (CT) scan found a solitary kidney on the right side with an opaque 4.5 cm × 2.4 cm renal stone and grade I hydronephrosis. Additionally, a urinary tract deformity was observed, and it was secondary to the deformity of the pelvis caused by a previous pubis fracture, which significantly increased the risk and the difficulty of intrarenal surgery. A total number of 3 sessions of RIRS were conducted, and the patient was discharged 3 days after each session on average. The postoperative X-ray exam of the third session revealed that the renal stone was completely removed. The patient recovered well without any complications. This case demonstrates that RIRS is a safe and effective treatment of staghorn calculi with the presence of urinary tract deformation. This suggests RIRS may be of particular interest in minimizing the procedure-related damage of a solitary kidney.