High-dose supplementation with vitamin C--induced pediatric urolithiasis: the first case report in a child and literature review.

High dose of vitamin C intake could increase urine oxalate excretion and hence the risk of calcium stone formation. We report a case of left ureteral stone in a 9-year-old boy with an extremely high urine oxalate excretion. Besides, he had a habit of taking high-dose supplementation of vitamin C since the age of 3 years. After vitamin C intake prohibited without other therapy and change of dietary intake, the urine oxalate excretion was decreased to normal level and no recurrence of urolithiasis was present during the 3-year follow-up. Thus, high-dose supplementation with vitamin C for years in a child could induce the urinary stones.