Medical Expulsive Therapy for Pediatric Ureteral Stones

Initial Management Approach

In pediatric patients with uncomplicated ureteral stones ≤10 mm, observation with or without medical expulsive therapy (MET) using alpha-blockers is recommended as first-line treatment, with a significant proportion of children passing stones spontaneously, averaging 62% for stones under 5 mm and 35% for stones >5 mm 1, 2
Alpha-blockers have been shown to facilitate stone passage in children through ureteral smooth muscle relaxation mediated by alpha-1 receptor blockade, although the American Academy of Pediatrics does not have a specific guideline, the American Urological Association recommends alpha-blockers for this purpose 3

Parents must be informed that alpha-blockers like tamsulosin are being prescribed in an off-label setting for this purpose, and the maximum duration for a trial of MET should be limited to six weeks to avoid irreversible kidney damage 1
Tamsulosin has been the most extensively studied alpha-blocker for MET, but current guidelines do not specifically recommend routine combination with corticosteroids for pediatric patients 3

Patients should be followed with periodic imaging studies to monitor stone position and assess for hydronephrosis, and pain should be well-controlled, with no clinical evidence of sepsis and adequate renal function maintained during the observation period 4

If MET fails or if the stone is unlikely to pass spontaneously, ureteroscopy (URS) or shock wave lithotripsy (SWL) should be offered, with stone-free rates in pediatric patients with ureteral stones <10 mm being high for both SWL (87%) and URS (95%) 1
For larger stones (>10 mm), stone-free rates are somewhat lower at 73% for SWL and 78% for URS, and SWL may be preferable in very small children or patients with challenging anatomy for ureteroscopic access 1
Complication rates are somewhat higher with URS (12.4%-20.5%) compared to SWL (8%-10%), according to the American Urological Association guidelines 1

Patients should be monitored for potential side effects of alpha-blockers such as dizziness, headache, and orthostatic hypotension, although these are less common in pediatric patients, and in cases of sepsis with obstructing stones, urgent decompression of the collecting system is required before any definitive treatment 1, 5, 6