Comparison of super-mini-percutaneous nephrolithotomy versus mini-percutaneous nephrolithotomy for renal calculi in children

Abstract

Objective To compare the safety and efficacy of super-mini-percutaneous nephrolithotomy (SMP) versus mini-percutaneous nephrolithotomy (MPCNL) in managing renal calculi in children. Methods Medical records were retrospectively reviewed for 40 children with renal calculi. They underwent SMP (n=18) and MPCNL (n=22). In SMP group, there were 14 boys and 4 girls with an age range of (7.90±4.40) years and a stone size of (15.41±5.63) mm; In MPCNL group, there were 14 boys and 8 girls with an age range of (8.62±3.41) years and a stone size of (16.77±3.59) mm. Operative duration, primary stone clearance rate, postoperative complications and other parameters of two groups were statistically analyzed for comparing the characteristics of two operative approaches. Results The time of establishing percutaneous renal channel was shorter in SMP group than that in MPCNL group [(10.75±2.70) vs. (19.68±6.95) min]. And inter-group difference was statistically significant (P=0.016). The first-phase stone clearance, postoperative hemoglobin loss and postoperative complication rate of SMP and MPCNL groups were (83.33±46.72) vs. (101.36±38.91) min, 83.33% vs. 81.81% and (7.59±7.51) vs. (7.75±8.77) g/L. respectively. No significant inter-group difference existed. No blood transfusion was provided. In SMP group, there was Clavien Ⅰ complication (n=1, 5.55%); In MPCNL group (n=5, 22.72%), postoperative fever subsided after aggressive anti-infection treatment. In two groups, there was on onset of Clavien Ⅱ/Ⅲ complications. Ultrasonic follow-ups were conducted for 1-2 years and hydronephrosis or renal atrophy disappeared in both groups. Conclusions Both SMP and MPCNL are safe, effective and mini-invasive for pediatric renal calculi. As compared with MPCNL, SMP has a smaller channel and a thinner mirror body. And SMP is more suitable for infants or toddlers with narrow calyx neck and lower calyx calculi. Key words: Renal calculus; Percutaneous nephrolithotomy; Child