Results of long-term rice bran treatment on stone recurrence in hypercalciuric patients.

A series of 182 calcium stone formers with idiopathic hypercalciuria underwent treatment with rice bran for 1 to 94 months. Urinary calcium excretion was considerably reduced, but there was some increase in urinary phosphate and oxalate. Urinary excretion of magnesium and uric acid, serum calcium, magnesium, phosphate, uric acid, parathyroid hormone (PTH) and ALP was unaffected. There were no obvious changes in serum iron, zinc and copper even when patients were treated for long periods. Rice bran was well tolerated in almost all cases and there were no serious side effects; 49 patients have undergone treatment for more than 3 years (average duration of administration 5.09 years). The frequency of new stone formation was drastically reduced (individual stone formation rate (no./year) from 0.720 +/- 0.533 to 0.125 +/- 0.204; group stone formation rate (no./patient-year) from 0.721 to 0.120) compared with the 3-year period before treatment. During treatment, 61.2% of patients remained in remission. Although rice bran therapy should be effective in correcting absorptive hypercalciuria, there may be limits to the overall ability of rice bran monotherapy to prevent recurrence.