title: Hereditary xanthinuria: report of two cases.
abstract: Hereditary xanthinuria is a rare disorder characterized by the replacement of uric acid by xanthine and hypoxanthine in urine. Two cases of classic hereditary xanthinuria in Taiwan are herein reported. Case 1: a 30-year-old woman was by chance found to have hypouricemia. Urine and plasma purines were checked through the use of high performance liquid chromatography. Urine excretion of uric acid was 0.029 mumol (0.005 mg)/mg creatinine (30 mumol/24 hr); xanthine 1.9 mumol/mg creatinine (1935 mumol/24 hr); and hypoxanthine 0.58 mumol/mg creatinine (587 mumol/24 hr). Plasma xanthine was 9.3 mumol/L; hypoxanthine 5.8 mumol/L; and uric acid 0.5 mumol/L (0.001 mg/dL). Case 2: a brother of case 1 had a previous history of urolithiasis. Urine excretion of uric acid was 0.15 mumol (0.025 mg)/mg creatinine (189 mumol/24 hr); xanthine 1.3 mumol/mg creatinine (1620 mumol/24 hr); and hypoxanthine 0.22 mumol/mg creatinine (276 mumol/24 hr).
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, R.O.C.
authors.forename: T S
authors.initials: TS
authors.lastname: Chu
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008661:Metabolism, Inborn Errors / Q000235:genetics / Q000652:urine*; D019820:Xanthine; D014969:Xanthine Oxidase / Q000172:deficiency*; D014970:Xanthines / Q000652:urine*
chemical_list: D014970:Xanthines; D019820:Xanthine; D014969:Xanthine Oxidase