[Obstructive ureteral calculi in children. Retrospective analysis of 24 cases]

To specify the characteristics of symptomatic ureteric stones in children and to define therapeutic indications for these stones.

Between 1993 and 2000, 24 children were treated for obstructive ureteric stones. The assessment comprised ultrasound and plain x-ray of the abdomen. A metabolic work-up and cystography +/- IVU were performed secondarily. First-line treatment consisted of medical treatment only in 34% of cases (8/24), piezoelectric extracorporeal lithotripsy (ESWL) (EDAP LT02) in 58% of cases (14/24) and ureteroscopy with ballistic fragmentation in 8% of cases (2/24).

This series consisted of 15 boys and 9 girls with a mean age of 6 years (range: 1 month to 15 years). The most frequent presenting complaints were renal colic in 14 cases and acute pyelonephritis in 7 cases. The obstructive ureteric stone was associated with urinary tract infection in 1/3 of cases. 12 children had a single stone and 12 children had multiple stones. The stone was situated in the pelvic ureter in 15 cases, the iliac ureter in 4 cases, and the lumbar ureter in 6 cases. The aetiological survey revealed hypercalciuria in 6 cases, cystinuria in 2 cases, and 4 urinary tract malformations. In 34% of cases (8/24), the stone was eliminated spontaneously (phi < or = 5 mm). 78% (11/14) of stones treated by ESWL (14/24) (mean phi = 8.3 mm) left no residual fragments with this treatment alone. The re-treatment rate was 36% (4/11). Three failures of ESWL were treated by ureteroscopy in 2 cases and surgery in 1 case. 92% (22/24) of these children were stone-free with a mean follow-up of 16 months.

Obstructive ureteric stones in children are associated with a high risk of infectious complications, justifying rapid and appropriate treatment. A metabolic abnormality must always be investigated and is present in 1/3 of cases. A stone diameter of 5 mm corresponds to the upper limit allowing spontaneous elimination during medical treatment. ESWL is the treatment of choice for ureteric stones greater than 5 mm in diameter, especially in the pelvic ureter. Ureteroscopy can be performed in children after failure of ESWL and for complicated stones.