Safety and efficacy of percutaneous nephrolithotomy in the pediatric population

Purpose: We reviewed our experience with percutaneous nephrolithotomy (PCNL) in patients in the pediatric age group and compared its efficacy and safety over a 5-year period. Patients and Methods: We studied retrospectively and prospectively 31 patients who were treated with PCNL for renal stones larger than 1.5 cm. Variables assessed were stone bulk, size, location, and type. Metabolic and anatomic factors were also assessed. PCNL punctures and number of tracts were recorded. Clearance with PCNL and ancillary procedures was recorded. Results: There were 31 renal units. Mean age of the patients was 9.6 years (range 1.5-15 years). Fifteen (48.4%) patients had single calculi; eight (25.8%) patients had staghorn calculi. Lower-pole access was the preferred route of entry, and upper-pole access was used only when necessary. We used a 22F nephroscope for the procedure. We dilated the tract to 30F in the majority of patients, but limited dilation to 24F when appropriate. If needed, we used a ureteroscope. Complete clearance was achieved in 83.9% of patients after PCNL and in 90.32% of patients after dual therapy (PCNL + shockwave lithotripsy). Average hemoglobin drop was less than 1 g/dl. Factors responsible were the size of the tract (larger than 24F) and the number of tracts. Six patients were treated for an anatomic abnormality. A metabolic abnormality was diagnosed in three patients. Conclusion: PCNL is effective in children, with a clearance rate of 83% and, with dual therapy, more than 90%. We recommend that tract dilation be restricted to 24F or smaller whenever possible. Approximately 40% of patients had either an anatomic or metabolic abnormality.