Lithotripsy in children. Multicentre study of the Paediatric Urology Study Group.

The authors present the results of a survey conducted among French paediatric urologists belonging to the Groupe d'Etudes en Urologie Pediatrique (GEUP) (Paediatric Urology Study Group). This study, based on 122 cases observed in 13 centres, is not exhaustive, but is nevertheless statistically significant. The preoperative assessment confirms the usual findings of urinary stones in children: pyelonephritis, haematuria and abdominal pain, the usual presenting complaint, concomitant malformative uropathy (10% of cases) and a predominance of calcium stones. More than 200 stones were treated, larger than 10 millimetres in diameter in one-third of cases. Renal stones, mainly caliceal (more than 50%), included 11 staghorn calculi. This study also included 22 ureteric stones, mainly in the pelvic ureter, and 2 bladder stones. Lithotripsy was ultrasound-guided in 2/3 of cases and required general anaesthesia in about 3/4 of cases. Ureteric catheterization was required in 19 infants preoperatively, but in only 2 infants (stein strasse) postoperatively. One or two lithotripsy sessions were sufficient in most cases, but 4 sessions were necessary in 5 patients, to the same kidney in 1 case. The mean hospital stay was 2 to 3 days, but the procedure was performed on an outpatient basis in 15 cases. The immediate postoperative course was uneventful and asymptomatic. This survey revealed about 10% of complete failures, corresponding to solitary caliceal stones in 2/3 of cases; 29 partial failures were essentially due to lower caliceal stones and staghorn calculi; 84 successes (stone-free), mainly pelvic or simple caliceal stones. Scintigraphy did not reveal any immediate postoperative impairment of renal function. This study reported a success rate of about 70 %, regardless of the type of apparatus used. Assessment of the results of ESWL requires sufficient follow-up both concerning the outcome of fragmented stones and evaluation of possible functional repercussions. This survey defines the main indications: although ESWL can be applied to most stones, some stones constitute poor indications (cystine stones, stenotic malformative uropathy) or dubious indications: small lower caliceal stones, densely calcified staghorn calculi in older children. This study confirmed the efficacy and low morbidity of ESWL in children. A prospective study needs to be conducted according to a rigorous protocol in order to refine the technique and indications while reducing the possible long-term risks.