[A study of allopurinol in the prevention of recurrent calcium oxalate stones].

We studied the effect of allopurinol on the prevention of stone recurrence in 134 patients with recurrent, idiopathic calcium nephrolithiasis. They consisted of 113 male patients and 21 female, between 16 and 72 years with an average age of 42.7. The patients were divided into two groups according to the type of stone occurrence; those with multiple stones without previous stone episodes (multiple stone group), and the those with recurrent stones (stone episode group). Twenty three patients belonged to the multiple stone group and 111 patients belonged to the stone episode group. The stones in 19 of the 23 patients in the multiple stone group remained stable throughout the study, while stones in 4 grew. Fifty-nine of the 111 patients in the stone episode group were free from recurrence, but the others showed recurrence. Statistical analyses was done on the stone episode group. The stone recurrence rate of all of the 111 cases showed significant decrease during prophylactic treatment with allopurinol (p less than 0.01), although the observation period before treatment was 73.0 +/- 65.8 months and that during and after treatment was 28.2 +/- 12.1 months. During the two years before and after prophylaxis 79 patients also showed a significantly decreased recurrence rate. Moreover, regarding 37 cases without any stones at the start of treatment, stone recurrence rate decreased significantly after the administration of allopurinol. Throughout this study, we used a new method for evaluating reasonable stone recurrence. It did not calculate the number of stones recurred, but the stone-forming circumstance in each kidney.(ABSTRACT TRUNCATED AT 250 WORDS)