The Probable Cause of Hypouricemia; Xanthinuria

Xanthinuria and hereditary renal hypouricemia usually leads to hereditary hypouricemia. Hypouricemia is defined as having serum uric acid level lower than 2 ml/dl. Xanthinuria is an autosomal recessive disease that can be occasionally seen in all ages. As a result of enzyme or cofactor deficiency, xanthine and hypoxanthine do not convert to uric acid and accumulate in the blood and increase the excretion in urine. The level of uric acid is detected very low either in serum or in urine. In this study, a case of a seventy-seven-year-old female patient in which hypouricemia was detected and who had the diagnosis of xanthinuria was discussed.