DETERMINATION OF URIC-ACID IN SCALP HAIR FOR NONINVASIVE EVALUATION OF URICACIDEMIC CONTROLS IN HYPERURICEMIA

The uric acid concentration in blood has been widely accepted asa diag nostic indicator of hyperuricemia and gout, and its assay method is we ll established, In the present study, we developed a simple and rapid method for the determination of uric acid in hair, which can be obtain ed non-invasively. The concentration (nmol/mg hair) of uric acid extra cted from 10-20 mg hair with 0.1M potassium hydroxide was determined b y an enzymatic method using uricase, The concentration of uric acid(nm ol/mg hair, mean +/- S.D.: 0.49 +/- 0.157, n=16) in hair from hyperuri cemic patients was significantly higher than that (0.26 +/- 0.107, n=8 ) in healthy volunteers (p<0.01), The within-run and between-day preci sion (CVs) of the assay was 9.6-10.3% (n=10 each) and 11.6-16.3% (n=7 each), respectively. The concentration (nmol/mg hair, y) of uric acid in hair correlated well with that in serum (mg/l, x): y=0.09 x=0.12 (r =0.75, S-yx=0.122, n=23). Changes in the concentration of uric acid in the hair of antihyperuricemic drug-treated patient paralleled that in serum, suggesting that the concentration of uric acid in hair is a re liable indicator of the metabolic control in hyperuricemia.