[Antioxidant enzyme activity in erythrocytes in children with kidney diseases]

An important place is ascribed to the formation and action of free oxygen radicals in the pathogenesis of some kidney diseases. The objective of the present work was to examine the antioxidant enzyme defence mechanism in children with different nephropathies.

In a group of 58 children (32 boys and 26 girls, mean age 13.9 years) with different renal diseases (35 children with chronic glomerulonephritis-GN, 8 children with a relapse of the nephrotic syndrome and 15 patients with chronic renal insufficiency-CHRI) the concentration of superoxide dismutase and catalase (KAT) was examined. The SOD and KAT activity in erythrocytes was assessed spectrophotometrically at 240 nm. In the whole group of patients the mean SOD values (632 +/- 102 U/g Hb) and KAT values (3.29 +/- 0.54 mukat/g Hb) were within the reference range. The highest mean SOD and KAT values were recorded in children with a relapse of nephrotic syndrome. In the group with chronic GN the SOD concentration in erythrocytes correlated significantly with total protein levels and serum creatinine resp. (r = 0.350, p < 0.05 and r = -0.458, p < 0.01 resp.). In the CHRI stage the authors revealed a significant relationship between the SOD activity and total protein levels (r = 0.550, p < 0.05).

The activity of basic antioxidant enzymes SOD and KAT in erythrocytes of children with nephropathies is not significantly reduced. In patients with chronic GN there is a significant correlation between renal functions and SOD.