title: Uric acid lithiasis associated with altered kinetics of hypoxanthine-guanine phosphoribosyltranferase.
abstract: 1. A patient is described who had uric acid calculi which obstructed both kidneys. Serum uric acid was 34 mg/100 ml upon admission to hospital, and evidence of precipitation of uric acid in joints was obtained. 2. Total activity of hypoxanthine-guanine phosphoribosyltransferase in erythrocytes lysates from this patient was 44% of normal. Kinetic studies revealed that the apparent Michaelis constant of this enzyme for phosphoribosyl pyrophosphate was elevated 15-fold, while these values for hypoxanthine and guanine were in the normal range.
mesh_terms: D000328:Adult; D006801:Humans; D007041:Hypoxanthine Phosphoribosyltransferase / Q000172:deficiency*; D007669:Kidney Calculi / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D014527:Uric Acid / Q000378:metabolism*
chemical_list: D014527:Uric Acid; D007041:Hypoxanthine Phosphoribosyltransferase