Zinc supplement in reduction of relapses in children with steroid sensitive nephrotic syndrome

Abstract

Objective: To determine whether Zinc supplementation could reduce relapse rate in children with nephrotic syndrome.

Study design: Randomized-controlled trial.

Place and duration of study: National Institute of Child-Health and The Kidney Centre, Karachi, from January 2008 to June 2009.

Methodology: Sixty nephrotic children aged 2 - 15 years were selected. Baseline data including age, number of infections and relapses during pre and post study one year were recorded. Randomization was done to divide into Zinc group (Zg) to receive Zinc versus placebo (Pg) for 6 months. Relapses and infections were treated with standard therapy. T-test and chi-square tests were used to compare the mean values and proportions respectively with significance at p < 0.05.

Results: Among 60 children, 54 completed trial (Zg = 25, Pg = 29). Forty (74%) were males and 14 (26%) females. Mean age, pre study relapses and Zinc level in the two groups were similar. Overall, infections and relapses were observed in 43 (79.62%) and 17 cases (31.48%) respectively. There was no significant difference in frequency of infections and mean infection rate in Zg (20, 80% and 1.92 ± 1.47) compared to Pg (23, 79.3% and 2 ± 1.53, p = 0.950). Relapses occurred in 7 (28%) in Zg compared to 10 (34%) in Pg which was not significant (p = 0.609). Mean infection and relapse rate per patient per year (PPPY) in Zg was 1.92 ± 1.47and 1.14 ± 0.37 compared to 2 ± 1.53 and1.3 ± 0.48 in Pg respectively (p=0.846, 0.464). Pre study relapses in two groups were similar (Zg vs. Pg = 96 vs. 96.6%) whereas post study relapses in Zg were lower (7, 28%) compared to Pg (10, 34.5%). Post study mean relapse rate in Zg was 1.14 ± 0.37 PPPY compared to 2.71 ± 1.11 in pre study (p = 0.005). In Pg, post study mean relapse rate PPPY was 1.30 ± 0.48 compared to 1.70 ± 0.48 in pre study period (p = 0.037). Relapse rate reduction was 43% after Zinc supplementation compared to 27% reduction in placebo. Metallic taste was observed in 10% of cases.

Conclusion: Zinc supplementation was helpful in reducing relapses in nephrotic syndrome.