[Effect of thiazide therapy in the prophylaxis of calcium lithiasis]

To analyze the role of thiazide therapy in the prevention of recurrent calcium nephrolithiasis, considering the hypocalciuric action of this drug.

A prospective study before and after treatment, with a 3-year follow-up, was carried out on 150 patients with recurrent calcium renal stone. The patients were divided into three groups: (A) no treatment, (B) treatment with thiazide 50 mg/day and (C) treatment with thiazide and potassium citrate. The treated groups were randomly assigned to the treatment arms. Control analytical tests and radiological assessments were performed regularly.

Excellent results were achieved with thiazide therapy in regard to stone recurrence and changes in residual stone in comparison to the group of untreated patients (group A). The most common metabolic disorder was absorptive hypercalciuria type I. Most of the patients showed a single metabolic disorder. The side effects were generally not relevant.

Thiazides should be considered as the first line of treatment in absorptive and excretory hypercalciuria. We believe that in unselected patients with calcium stone, thiazide therapy can be effective in its prevention. It is important to take into account the possible side effects of the drug and supplementation with potassium citrate for thiazide-induced hypocitraturia.