Plasma protein thiols and total antioxidant power in pediatric nephrotic syndrome

Background: Oxidative damage by free radicals has been implicated in kidney injury, especially in nephrotic syndrome (NS). Such a stress would influence the response of nephrotic children to therapy. Methods: The present study enrolled children with NS in active disease state and in remission and 50 healthy volunteers. Plasma protein thiol levels and ferric-reducing/antioxidant power were estimated spectrophotometrically in controls and in patients. Serum protein and albumin as well as urine protein were also estimated. Results: There was a significant decrease in plasma protein thiol levels in children with active disease when compared to controls as well as to subjects in remission. Ferric-reducing/antioxidant power values were significantly increased in NS and remained high in remission when compared to controls. Serum total protein and albumin were significantly decreased in nephrotics compared to controls. Further, a prospective study between the relapse and remission groups indicated a significant increase in plasma protein thiols in remission when compared to relapse exhibiting a positive response to treatment. Conclusion: A considerable alteration in the antioxidant status in NS indicates the pro-oxidant milieu existing in this condition which may have implications in the response to treatment of these patients.