Laparoscopy-assisted transperitoneal percutaneous nephrolithotomy for recurrent calculus in isthmic calix of horseshoe kidney

BACKGROUND AND PURPOSE: Management of urolithiasis in a horseshoe kidney (HSK) poses a unique challenge. Although most patients can be managed by a combination of percutaneous nephrolithotomy (PCNL) and extracorporeal shockwave lithotripsy (SWL), calculi in the isthmic calix remain difficult to treat, as this area is out of reach during rigid PCNL, and, owing to the poor evacuation of the fragments, the results of SWL are suboptimal. CASE REPORT: A 59-year-old man known to have an HSK presented with right-sided lower-abdominal pain and episodes of urinary infection. In the past, he had undergone pyelolithotomy and lithotripsy for lithiasis in the kidney. Imaging studies identified a large recurrent calculus in the anteriorly directed isthmic calix. This was treated successfully by a laparoscopy-assisted transperitoneal PCNL. The laparoscopic view allowed the bowel to be retracted away from the site of the HSK, and PCNL guided by fluoroscopy and laparoscopy was performed. Complete stone clearance was achieved in a single stage. The patient remains free of symptoms and recurrence 3 months later. CONCLUSION: We believe this to be the first report describing this novel approach to lithiasis in an HSK.