Study of Xanthine Oxidase Activity in Sera of Iraqi Children with Nephrotic Syndrome

Abstract

Introduction: To investigate the relationship of xanthine oxidase activity with nephrotic syndrome disorder in children, and the optimization of the enzyme activity conditions in the disorder. Material and methods: Sera of children with nephrotic syndrome (NS) (60 samples) were obtained from Central Child Teaching Al Karama Hospital (CCTAH), from 2nd Mar. 2013 to 28th Feb. 2014. Sera of the patients were assayed for xanthine oxidase (XO) activity using colorimetric absorbance technique. The obtained results were compared with the enzyme activity of normal children (70 samples) as control. Results and conclusions: The results revealed a significant (P < 0.001) elevation in XO activity in serum of nephrotic syndrome (0.12 ± 0.06 IU/L) compared with that of normal subjects (0.05 ± 0.009 IU/L), showing an elevation of (70%) in XO activity (about 2/3) that of normal group. Factors influencing XO activities were also studied and showed that XO activity is a pH dependent. Significant elevation (P < 0.001) was found in uric acid level in sera of NS patients (497.52 ± 3.21 μmol/L) compared with that in normal group (298.12 ± 1.70 μmol/L). Elevation was found in urea level in sera of NS patient (10.69 ± 7.55 mmol/L) compared with that of normal group (4.57 ± 1.27 mmol/L). It was appeared, there is a role of XO activity in the pathogenesis of endothelial injury during glomerular lesion in NS and that was confirmed by comparing XO activity and other related conditions with the activity of normal volunteers.