Xanthuria

Xanthuria. — Voiding of urine depositing xanthin.

Xanthuria is an hereditary disorder in which there is an absence of the enzyme xanthine oxidase which interferes with the metabolic breakdown of purines, leading to an increased excretion of xanthine in the urine and to formation of stones.

Xanthine calculi are seen in patients with hereditary xanthuria and those undergoing treatment with allopurinol.