RESUMO
Recently obesity in pediatric population is rising fast and its early onset complications [like those seen in adults] are keeping pace with it. It seems that a high level of urinary uric acid [UUA] could be the result of reproduction of uric acid in the body. On the other hand, it was shown to be the result of decreased urinary clearance of uric acid in some obese adults. Target of study is the mechanism of hyperuricemia in obese children and also the correlation between hyperuricemia and factors related to the obesity. We studied 75 severely obese children [42 boys and 33 girls] and compared them with 30 non-obese children [20 boys and 10 girls]. Serum leptin, lipid profile, liver tranaminases, uric acid and creatinine and also 24 hours urinary uric acid and creatinine were measured, and uric acid clearance was calculated in each case. Serum uric acid level [U.A] in obese children were significantly higher than those in control children, but urinary uric acid [UUA], uric acid clearance [CUA] and fractional excretion of uric acid [FEUA = CUA/CCR * 100] were lower in the obese children than those in controls. The low UUA in the obese children suggests that their hyperuricemia was not the result of over intake of food containing uric acid. There was a close correlation between uric acid and age/body weight and it becomes closer as they aged and gained weight. These results suggest that hyperuricemia in obese children is mainly attributable to impaired renal clearance of uric acid and not to overproduction in the body and it will higher age and body weight