PROPHYLAXIS FOR ACETAZOLAMIDE INDUCED UROLITHIASIS

CLINICAL STUDY

Abstract

It is well known that acetazolamide induces urolithiasis. But there have been no reliable prophylactic measures up to the present time. This paper presents a successful prophylactic treatment for the iatrogenic urolithiasis.
Comparative studies were made between 19 no stone-forming patients as the control and 19 glaucoma patients administered acetazolamide. In the latter, there were significant rises of serum ionized calcium/total calcium ratio and increase of urinary calcium excretion. It was considered that both phenomena were owing to metabolic acidosis induced by the long-term administration of acetazolamide.
Twenty-six glaucoma patients were given citrate (K₃ citrate; 8-10g/day and Na₃ citrate; 4-6g/day per os.) for the correction of metabolic acidosis.
Before taking citrate, 11 out of 26 patients had 26 stone episodes in 1.5 years, i. e., an average of 1.58 stone episodes per patient per year. Nine patients who had received citrate therapy in 1.5 years had only one stone episodes i. e., an average of 0.07 stone episodes per patient per year. During the follow-up periods, it was elucidated that citrate administration did not affect the intraocular pressure decreaing action of acetazolamide, and as expected, decreased serum ionized calcium/total calcium ratio and urinary calcium excretion.
Prophylactic effects of citrate administration is considered to be due to the improvement of metabolic acidosis and subsequent decrease of serum ionized calcium/total calcium ratio and urinary calcium excretion.