Percutaneous nephrolithotomy for calculi in horseshoe kidneys.
 Between 1983 and 1988, 15 patients (18 kidneys) underwent percutaneous nephrolithotomy at this unit for calculi in horseshoe kidneys.
 A standard 1-stage percutaneous access technique with minor modifications was used.
 In situ disintegration with ultrasound or electrohydraulic lithotripsy was necessary in 15 moieties (83.3%) and nephrostomy drainage was required in 12 (66.7%).
 Percutaneous access was not a problem and there were minimal perioperative problems.
 Blood transfusion was required postoperatively in 2 patients.
 A total of 14 kidneys (77.8%) were rendered free of stone with percutaneous nephrolithotomy alone and 2 kidneys were left with asymptomatic stone fragments of 2 mm.
 or less.
 Another 2 kidneys became free of stone after extracorporeal shock wave lithotripsy, thus giving an over-all stone clearance rate of 88.8%.
 We conclude that percutaneous nephrolithotomy is an acceptable treatment for stones in horseshoe kidneys and it is the treatment of choice for patients in whom imaging is difficult or impossible.
