Successful sodium thiosulphate treatment for recurrent calcium urolithiasis.

Thirty-four idiopathic rapid calcium stone formers (24 male/10 female) were studied. Their ages ranged from 20 to 60 years (40 +/- 11) and all had good renal function. The trial comprised two consecutive periods of 3 years and 4 years duration respectively. In the first (control period), the patients were maintained on a customary diet with an adequate fluid intake sufficient to produce about 2 liters of urine daily. In the second (treatment period), they received a similar diet plus 20 mmol of sodium thiosulphate daily. New stone development fell from 100 in the control period to 15 in the treatment period, corresponding to a rate of 0.98 and 0.11 per year (p less than 0.001). It is suggested that the benefit from sodium thiosulphate results from calcium thiosulphate formation in urine, a salt with a molar solubility of 250 to 100.000-fold greater than that of other urinary calcium salts.