痛風高尿酸血症の尿酸クリアランス法による検討

For estimation of uric acid metabolism of hyperuricemia in patients with gout, uric acid clearance and urinary excretion of urate were determined in 150 cases of gout and 10 normal controls. Mean and standard deviation of the clearance and the urinary excretion of the controls were 9.4 ±1.6 ml/min and 0.52 ±0.10 mg/kg/hr, respectively. Therefore, cases with uric acid clearance under 6.1 ml/min were defined as underexcretion type, those under 3.9 ml/min were as severe underexcretion type. Regarding the urinary excretion of urate, cases with the excerion over 0.73mg/kg/hr should be defined as overproduction type. However, because ratio of urinary excretion to synthesis of urate in patient with gout were generally lower than those of the controls and 90%of patients who had urinary excretion over 0.50 mg/kg/hr were overproduction type in the urate-14C turnover study as reported previously, we assumed that those with urinary excretion over 0.50 mg/kg/hr were overproduction type. By the criteria,150cases of hyperuricemia were classified into 6 groups, that is, overproduction type, overproduction with moderate underexcretion type, overproduction with severe underexcretion type, moderate underexcretion type, severe underexcretion type and normal production and excretion type, which were 29 cases (19.3%),23cases (15.3%) 1 case (0.7%),38 cases (25.3%) 57 cases (38.0%) and 2 cases (1.4%) respectively.<BR>Serum uric acid level of overproduction type was generally lower than that of underexcretion type but urinary excretion, uric acid clearance, creatinine clearance and clearance ratio of overproduction type were generally higher than those of underexcretion type.<BR>Significant positive correlation were demons t r ated between uric acid clearance and urinary excretion (r=0.77), uric acid clearance and clearance ratio (r=0.66), uric acid clearance and creatinine clearance (r=0.40), creatinine clearance and urinary excretion (r=0.28), and significant negative correlation were obtained between serum uric acid level and uric acid clearance (r=-0.54), creatinine clearance and clearance ratio (r=-0.34), serum uric acid level and clearance ratio (r=-0.29), serum uric acid level and creatinine clearance (r=-0.26), respectively.<BR>To estimate production of uric acid in hyperuricemia of gout more precisely, modification of the clearance method was discussed.