HYPERURICEMIA IN CYANOTIC CONGENITAL HEART-DISEASE

This study examines the exacerbating factors of hyeruricaemia in patie nts with cyanotic congenital heart disease (CCHD). We studied 59 CCHD patients aged 1 month-30 years. The following variables were assessed: serum uric acid levels, red blood cell count, haemoglobin, hematocrit , partial oxygen pressure and arterial oxygen saturation. Uric acid ex cretion and renal function were also measured in ten patients with ser um levels of uric acid greater than 8 mg/dl (hyperuricaemia group). Se rum uric acid level correlated significantly with age and severity of polycythaemia. However, it did not correlate with partial oxygen press ure or arterial oxygen saturation. Uric acid excretion was measured in hyperuricaemia group. Urinary uric acid excretion (24 h) was within n ormal limits in infants but markedly lower in patients over 15 years o f age. The aetiology of hyperuricaemia and decreased uric acid fractio nal excretion and clearance in infants appears to be secondary to dimi nished excretion of uric acid in concert with uric acid overproduction . Hyperuricaemia in adolescents and adults with CCHD, however, results mainly from age-related impairment of uric acid excretion.