EFFECT OF EXTRACORPOREAL SHOCK-WAVE LITHOTRIPSY ON RENAL-FUNCTION AND BODY HEIGHT IN PEDIATRIC-PATIENTS

Although extracorporeal shock wave lithotripsy (ESWL) is the preferred modality for treatment of most renal and upper ureteral calculi in adults, little is known about its effect on the pediatric population. We carefully followed 12 children 2.2 to 15.3 years old (mean age 9.4) treated with the Dornier HM3 lithotriptor. Effective renal plasma flow was obtained by quantitative iodine-131 hippurate scan immediately preceding ESWL and at followup (range 74 to 238 weeks, mean 149). The treated kidney received an average of 1,702 shocks (range 1,000 to 2,200). Mean effective renal plasma flow increased in the treated kidney from 185 cc per minute before ESWL to 217 at followup (p = 0.016) and in the untreated kidney from 191 to 224 (p = 0.0013). Total effective renal plasma flow increased from 376 cc per minute before ESWL to 440 at followup (p = 0.0019). In the treated kidney mean and total effective renal plasma flow increased by 31 (expected 32) and 64 (expected 68) cc per minute, respectively, while in the nontreated kidney mean effective renal plasma flow increased by 33 (expected 36) cc per minute. None of the observed changes in effective renal plasma flow was significantly different from the expected changes using the paired t test at the 95% level. In addition, change in body height was evaluated using standard deviation scores. Mean body height (standard deviation) before ESWL was -0.39 (range -3.2 to 2.0) and at last followup it was -0.26 (range -2.6 to 2.4), which is not statistically significant (p = 0.37). Although these patients continue to be followed and caution is advised, this long-term study indicates that ESWL within the range of shocks delivered to this cohort does not statistically affect linear growth (body height) or renal function in the pediatric population.