[Calcium nephrolithiasis and phosphate therapy. Long term study (65 cases) (author's transl)].

Protected phosphate therapy was used in 65 cases of recurrent calcium nephrolithiasis. Mean duration treatment was 2 years and 1 month (more than 3 years in 17 cases). Mean lithiasis episodes by year-patients were 1,55 renal colics and 0.34 stone formation before phosphate treatment, versus 0.66 renal colics and 0.10 stone formation (more than 60% reduction), during treatment. There was simultaneously decrease of hypercalciuria (24 cases out of 42), of asthenia (16 cases out of 19), of signs of spasmophilia (12 cases out of 18) and disappearing of bone pains (4 cases out of 6). Side effects were rare. Minor digestive troubles were observed in 11 cases: diarrhea (3 cases) or gastralgias (9 cases). These side-effects necessitated discontinuation of thiazide therapy in only two cases and reduction of doses in 6 other cases. From our data, phosphate therapy appears an efficient drug in recurrent calcium nephrolithiasis. It acts in reducing levels of calciuria and enhancing urinary pyrophosphates excretion, inhibitors of calcium crystallization.