Hypouricemia Due to Increased Tubular Secretion of Urate in Children with Amanita phalloides Poisoning

Abstract

The tubular transport of urate was studied in 20 children poisoned with Amanita phalloides and in control group. The aim of this study was to investigate the cause of repeatedly observed episodes of hypouricemia in patients after A. phalloides poisoning. A significant negative correlation between serum uric acid concentration and fractional excretion of urate in poisoned and control groups (r = 0.73, p < 0.001) was found. The results of pyrazinamide and probenecid tests performed in patients after A. phalloides poisoning indicated that hyperuricosuria was most likely due to an increment in renal tubular urate secretion, and not due to decreased presecretory and postsecretory reabsorption of uric acid. These findings indicate that hypouricemia found after A. phalloides poisoning in children is of renal origin due to an increase in tubular urate secretion.