Anti-oxidant vitamins and steroid responsive nephrotic syndrome in Indian children

In recent years, it has been proposed that nephrotic syndrome is a consequence of an imbalance between oxidant and anti-oxidant activity. In the present study, the levels of micronutrient anti-oxidant vitamins (vitamin E, vitamin C, carotene and riboflavin) in Indian children with steroid responsive nephrotic syndrome were investigated. Their levels were measured during the acute proteinuric phase of the disease, as well as during clinical recovery (remission), in order to understand the possible role of nutritionally modifiable anti-oxidants in the aetiopathogenesis of the disease.

The study was a hospital based, prospective cohort study. Serum and erythrocyte vitamin E, leucocyte vitamin C, serum carotene, erythrocyte riboflavin activity and serum malonyldialdehyde (MDA) levels were measured in 30 consecutive cases of children with nephrotic syndrome (International Study of Kidney Diseases in Children (ISKDC) criteria) during the proteinuric phase of the disease and at 4 weeks after remission was induced by steroid therapy. The same biochemical parameters were measured in healthy siblings (controls) of the 30 patients.

Mean vitamin E (serum and erythrocyte), vitamin C and carotene were significantly lower during the proteinuric phase of the disease, and there was decreased erythrocyte riboflavin activity. There was significant elevation in the serum level of MDA during this phase. In addition, all these parameters tended to improve during remission, although complete normalization did not occur.

These vitamins were active in performing their anti-oxidant function, as indicated by significant depression in their levels during the acute (proteinuric) phase, followed by partial recovery during remission. It may be concluded that steroid responsive nephrotic syndrome in children is associated with oxidative stress.