Xanthinuria, also known as xanthine oxidase deficiency, is a rare

genetic disorder A genetic disorder is a health problem caused by one or more abnormalities in the genome. It can be caused by a mutation in a single gene (monogenic) or multiple genes (polygenic) or by a chromosome abnormality. Although polygenic disorders ...

causing the accumulation of

xanthine Xanthine ( or , from Ancient Greek for its yellowish-white appearance; archaically xanthic acid; systematic name 3,7-dihydropurine-2,6-dione) is a purine base found in most human body tissues and fluids, as well as in other organisms. Several ...

. It is caused by a deficiency of the

enzyme An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...

xanthine oxidase Xanthine oxidase (XO or XAO) is a form of xanthine oxidoreductase, a type of enzyme that generates reactive oxygen species. These enzymes catalyze the oxidation of hypoxanthine to xanthine and can further catalyze the oxidation of xanthine to ...

. It was first formally characterized in 1954.

Presentation

Affected people have unusually high concentrations of xanthine in their blood and urine, which can lead to health problems such as

renal failure Kidney failure, also known as renal failure or end-stage renal disease (ESRD), is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels. Kidney fa ...

and xanthine kidney stones, one of the rarest types of kidney stones.

Causes

Type I xanthinuria can be caused by a deficiency of

, which is an enzyme necessary for converting

uric acid Uric acid is a heterocyclic compound of carbon, nitrogen, oxygen, and hydrogen with the Chemical formula, formula C5H4N4O3. It forms ions and salts known as urates and acid urates, such as ammonium acid urate. Uric acid is a product of the meta ...

. Type II xanthinuria and molybdenum cofactor deficiency lack one or two other enzyme activities in addition to xanthine oxidase.

Diagnosis

Treatment

There is no specific treatment beyond maintaining a high fluid intake and avoiding foods that are high in

purine Purine is a heterocyclic aromatic organic compound that consists of two rings (pyrimidine and imidazole) fused together. It is water-soluble. Purine also gives its name to the wider class of molecules, purines, which include substituted puri ...

References

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External links

* {{Purinergics Inborn errors of purine-pyrimidine metabolism