Efficacy of kidney stone management through extracorporeal shock wave lithotripsy at a tertiary care center in Mexico City

Abstract

Background: The incidence of urinary lithiasis in children is low (~3%). Extracorporeal shockwave lithotripsy is a first-line therapeutic alternative for kidney stones smaller than 20 mm. However, it has the disadvantage of a variable success rate (after the first session it varies from 60 to 90%) that is directly associated with stone size, density, and composition. The predictive factors for success of the procedure are stone load, lower infundibular length, and the infundibulopelvic angle (> 45o).

Objective: To determine the overall efficiency of extracorporeal shock wave lithotripsy as treatment for kidney stones in the pediatric population at the Hospital General de México.

Material and methods: : A cross-sectional, analytic, retrospective study included 45 case records of pediatric patients that underwent extracorporeal shock wave lithotripsy as kidney stone management. The inclusion criteria were patient age from 1 to 18 years, stone diameter  20 mm, and stone located in the kidney; the exclusion criteria were patients > 18 years of age, stone diameter > 20 mm, stone located outside the kidney, obstruction, pregnancy, or blood dyscrasia; and the elimination criteria were patients with no radiologic follow-up (1 month).

Results: Kidney stones were resolved in 28 patients, resulting in a success rate of 62.2% (95% CI: 47.5-77.0). The factors associated with therapeutic failure were stone size (p=0.03) and stone location in the kidney unit (p= 0.03).

Conclusions: Our study results were similar to those reported in the literature for the management of kidney stones in the pediatric population, with respect to safety, efficacy, and stone-free status.