Percutaneous nephrolithotomy in children: early and late anatomical and functional results

PURPOSE: We report our experience with percutaneous nephrolithotomy (PCNL) in children, and evaluate its early and late anatomical and functional results. MATERIALS AND METHODS: A total of 65 children with renal calculi were treated with PCNL. Patient age at operation ranged from 9 months to 16 years (mean +/- SD of 5.9 +/- 0.9 years), and 27 (41.5%) were younger than 5 years. Seven patients had bilateral renal stones and, therefore, the number of kidneys treated by PCNL was 72. The patients were followed regularly every 3 months during year 1 and every 6 months thereafter. Renal scans using technetium dimercapto-succinic acid for detection of renal scarring and technetium diethylenetetramine-pentaacetic acid for determination of selective glomerular filtration rate (GFR) were performed in all patients at least once during followup, which ranged from 6 to 72 months (mean +/- SD 40 +/- 10). RESULTS: Early complications included significant intraoperative bleeding in 1 case, renal pelvis perforation in 1 and transient fever in 2. Mean hospital stay +/- SD was 3 +/- 1.2 days (range 2 to 21). Of the renal units 62 (86%) were stone-free after a single PCNL, and the remaining 10 with residual stones were treated with a second look PCNL (4) and shock wave lithotripsy (6). Stone-free rates at hospital discharge and at 3 months were 93% and 100%, respectively. During followup 6 patients (9%) had recurrence of small renal stones and were successfully treated with shock wave lithotripsy. None of the kidneys had scarring on dimercapto-succinic acid renal scan. All of the kidneys except 1 showed improvement or stabilization of the corresponding GFR determined by diethylenetetraminepentaacetic acid renal scan. Comparison of the mean preoperative GFR of the corresponding kidney (28.8 +/- 11.2 ml per minute) with mean value at followup (36.1 +/- 9.9) showed an increase of statistical significance (p <0.01). CONCLUSIONS: PCNL is a safe and effective procedure for the treatment of children with renal calculi. At long-term followup the procedure improves renal function without renal scarring.