Ureteropelvic junction obstruction with concurrent renal pelvic calculi in the pediatric patient: A long-term followup

Purpose: We determined the long-term prognosis of the pediatric patient presenting with simultaneous ureteropelvic junction obstruction and a renal calculus. Materials and Methods: We retrospectively reviewed all individuals younger than 17 years who presented to our institutions with simultaneous ureteropelvic junction obstruction and an ipsilateral renal calculus. Results: Simultaneous ureteropelvic junction obstruction with nonstruvite calculi was present in 22 patients, while 6 had struvite calculi. Median age at diagnosis was 11 years (range 5 to 16). During a median followup of 9 years (range 2 to 38) renal calculi recurred in 19 patients (68%), including 10 (36%) with 1 and 9 (32%) with 2 or more recurrences. Median time to first stone recurrence was 11 years (range 2 to 38). Of the 22 patients with nonstruvite calculi 15 (68%) had recurrence. An identifiable metabolic etiology for renal lithiasis was found in 13 of these patients (87%). In contrast, only 2 of the 7 patients (29%) with nonstruvite calculi and no recurrent stones had an identifiable abnormality. This finding suggests that the presence of an identifiable metabolic abnormality significantly predisposes to recurrent nonstruvite renal lithiasis (p <0.01). Conclusions: Of the pediatric patients presenting with simultaneous ureteropelvic junction obstruction and a renal calculus 68% will have recurrent renal lithiasis. It remains to be determined whether active treatment of coexisting metabolic abnormalities could prevent or reduce the incidence of recurrent stone disease.