Comparison of two percutaneous nephrolithotomy methods for the treatment of pediatric kidney stones: mini-percutaneous nephrolithotomy and standard percutaneous nephrolithotomy.

Objective: In this study, the aim was to compare the results of mini and standard percutaneous nephrolithotomy (PCNL) for the treatment of pediatric kidney stones.

Materials and methods: Data for 128 patients < 18 years of age who underwent mini and standard PCNL due to pediatric kidney stones were retrospectively examined. Patients were divided into two groups: mini-PCNL (16-20 Fr) and standard PCNL (26 Fr). Surgery time, number of punctures to the pelvicalyceal system, hospital stay, postoperative hemoglobin drop, complications and stone-free status (SFR) were compared between the groups. Additional surgical intervention (double-J stent, ureterorenoscopy, secondary PCNL) performed after the surgery was recorded. The absence of residual stones or < 3 mm residual stones on kidney, ureter and bladder radiography (KUB) and ultrasonography (USG) performed in the third postoperative month were accepted as success criteria.

Results: There were 32 (43.8%) patients in the mini-PCNL group and 41 (56.2%) patients in the standard PCNL group. The mean age was 9.3 ± 4.1 years in the mini-PCNL group and 10.1 ± 5.4 years in the standard PCNL group. Mean stone size in the mini-PCNL group was 2.1 ± 1.2; while for standard PCNL it was 2.3 ± 1.4. The mean surgery time was statistically significantly higher in the mini-PCNL group (p = 0.005). There was no difference between the groups in terms of intraoperative double J stent use, postoperative complications and SFR. A double J stent was inserted in two patients in the mini-PCNL group and in one patient in the standard PCNL group due to urine leakage from the nephrostomy tract in the postoperative period. Although the postoperative hemoglobin drop was found to be significantly higher in standard PCNL (p = 0.001), hematuria and blood transfusion rates were low in both groups. Mean hospital stay was shorter in the mini-PCNL group compared to standard PCNL (3.6 ± 1.2 days vs. 2.5 ± 1.1; p = 0.018).

Conclusions: Although mini-PCNL has longer surgery time compared to standard PCNL, it should be preferred for the treatment of pediatric kidney stones due to advantages such as similar success and complication rates to standard PCNL, short hospital stay and less postoperative hemoglobin drop.