The Safety and Efficacy of Percutaneous Nephrolithotomy for Management of Large Renal Stones in Single-Versus Double-Functioning Kidney Patients

Purpose: To demonstrate the safety and efficacy of percutaneous nephrolithotomy (PCNL) for management of large renal stones between single-functioning kidney and double-kidney patients. Patients and Methods: Thirty single-functioning kidneys and 30 double-kidney patients with a mean age of 38.5 (+/- 15.6) years in the single group and 42.1 (+/- 14.3) years in the double group (range 11-72 years) underwent PCNL for renal stones larger than 2 cm. The effect of PCNL on global and regional cortical activity was measured using quantitative single-photon emission CT measurement of technetium-99m (Tc-99m) dimercaptosuccinic acid (DMSA) scan uptake by the kidneys before and 6 months after PCNL. Variables assessed were stone bulk, size, location, the number of punctures, and anatomic factors. Average hemoglobin and serum creatinine changes, mean operative time, transfusion rate, hospital stay, and different complications were also assessed. Results: Mean stone size, mean hospital stay, success rate, and complications were statistically similar in both groups. Mean serum creatinine changes (preoperative and postoperative) were not statistically significant between the two groups (P = 0.12). Mean hemoglobin drop (preoperative and postoperative) in both groups was significant, and there was a valuable difference between them (P = 0.01). There was a significant difference in the uptake by the treated kidneys before vs after PCNL between both groups statistically (P = 0.019), so that the DMSA renal uptake was obviously higher 6 months after PCNL in the double-kidney group compared with its uptake in the single-functioning kidney group. Conclusion: Tc-99m-DMSA renal scan confirms that renal function was preserved or even often improved after percutaneous stone removal, and the procedure had no detrimental effects on renal function in both groups. There was no statistically significant difference between these groups in terms of morbidity and stone clearance.