High fluid intake or pharmacological therapy in recurrent stone former patients?

In order to evaluate whether therapy can reduce relapses of urinary stone formation, we have retrospectively analysed the long-term follow-up of 55 recurrent stone former patients either treated with high fluid intake and moderate low calcium and low oxalate diet alone (Group A 18 patients), or with the same dietetic advice plus hydrocholorothiazide, amiloride and allopurinol (Group B 37 patients). In group A, stone recurrence was completely abolished in 14 patients without hypercalciuria and hyperuricuria, but not in the four patients with hypercalciuria and hyperuricuria. In group B, no relapses were observed in 19 hypercalciuric and hyperuricuric patients during a cumulative follow-up of 91 years. Even if the other 18 patients had relapses during a cumulative follow-up of 89 years, they showed a significant decrease in stone/patient and stone/year rates. It is concluded that high fluid intake and diet can actually prevent stone recurrence in patients without hypercalciuria and hyperuricuria, but in hypercalciuric and hyperuricuric patients treatment with diuretic and allopurinol is better.