Xanthinuria

What it means

An increased concentration of xanthine in the urine.

Xanthinuria is generally caused by a defect in the xanthine oxidase, an enzyme that catalyzes the oxidation of hypoxanthine to xanthine and can further catalyze the oxidation of xanthine to uric acid. The formation of xanthine stones in the urinary tract is the main evidence of this abnormality.

Rare diseases that can present with this1

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Increased urinary xanthine