Urolithiasis in childhood acute leukemia and nonHodgkin's lymphoma.

Ureteral calculi were found in 5 children who were receiving or had recently completed remission induction therapy for acute leukemia or lymphoma. All 5 patients had abdominal or back pain and 3 had gross hematuria. The diagnosis of urolithiasis was suggested by excretory urograms that showed obstructive uropathy (4 patients) and by computerized tomography scans that demonstrated ureterovesical obstruction (1 patient with acute renal failure and anuria). With a single exception the calculi were not associated with urinary tract infections. Chemical analyses in the 2 patients tested indicated that the stones were composed of calcium, in contrast to the uric acid and xanthine compositions of stones in earlier studies of patients with leukemia or lymphoma. Factors that might have predisposed our patients to calculi formation include corticosteroid therapy, immobilization owing to bed rest and urinary alkalization. Other possible contributing factors were urinary stasis (2 patients) and a familial tendency for renal calculi to develop. There was no evidence of idiopathic hypercalciuria in either patient tested. Prompt detection of urolithiasis in children undergoing induction chemotherapy for a malignant disease may avoid potentially serious consequences from urinary tract obstruction.