Mondo Description Type I xanthinuria, a type of classical xanthinuria, is a rare autosomal recessive disorder of purine metabolism characterized by the isolated deficiency of xanthine dehydrogenase, causing hyperxanthinemia with low or absent uric acid and xanthinuria, leading to urolithiasis, hematuria, renal colic and urinary tract infections, while some patients are asymptomatic and others suffer from kidney failure. Less common manifestations include arthropathy, myopathy and duodenal ulcer.

Uniprot Description A disorder characterized by excretion of very large amounts of xanthine in the urine and a tendency to form xanthine stones. Uric acid is strikingly diminished in serum and urine. XAN1 is due to isolated xanthine dehydrogenase deficiency. Patients can metabolize allopurinol.