[Incidence of lithiasic recurrence after a diuretic therapy, alone or combined with treatment by a thiazide diuretic or phosphorus].

The preventive affects on recurrent renal calcium stones of water diuresis alone or combined with drugs aimed at lowering urinary calcium were evaluated prospectively in 51 patients with calcium nephrolithiasis. Following clinical and metabolic examination, the patients were allocated at random to 3 treatment groups: water diuresis alone (group I, n = 19) or associated with hydrochlorothiazide 50 mg/day (group II, n = 19) or with a neutral phosphate preparation 1500 mg/day (group III, n = 13). Results were assessed on the number of recurrences; 24-h urinary calcium was measured at regular intervals. The mean follow-up (2 years; range 1-4 years) was the same in all 3 groups. A significant fall in recurrence rate as compared with pre-treatment values was observed in groups I and II. The recurrence rate was the same in both groups during treatment. However, less patients had recurrences in group I (1/19) than in group II (5/19). No significant fall in recurrence rate was observed in group III, owing to some patients in this group having frequent recurrences. The recurrence rate was unrelated to clinical findings and biochemical values ( oxaluria , calciuria) measured before treatment and to the urinary Ca/Cr ratio calculated during treatment. This study confirms that water diuresis is effective in preventing recurrent renal calcium stones and that diuretics of the thiazide group reduce the number of patients with recurrences.