[Dietary control for out-patients in urinary stone clinic]

We studied the dietary habits of 113 upper urinary tract stone formers and 24-h urine specimens before and after dietary control. Protein intake was decreased in male patients after dietary control but urinary risk factors were not changed significantly. The excretion of urinary risk factors (calcium, uric acid and oxalate) was decreased in the patients who had calcium excretion of more than 250 mg per day or uric acid excretion more than 650 mg per day or oxalate excretion more than 45 mg per day before the control. The daily protein intake was significantly correlated to urinary uric acid, calcium, and phosphate excretion and the daily vitamin C intake to urinary citrate excretion. There was a negative correlation between the daily calcium intake and urinary oxalate. The mean stone episode rate of these patients was significantly decreased from 0.174 to 0.059 stones per year by dietary control (p < 0.005).