The Role of Zinc in the Evolutionary Pattern of Pediatric Nephrotic Syndrome: A Meta-Analysis

Nephrotic syndrome (NS) is a chronic pathology, with an undulating evolution, that reduces the quality of life among children.

In this meta-analysis we sought to assess the reliability of zinc supplementation in reducing the relapse prevalence and morbidity associated with pediatric NS.

We searched the PubMed, Web of Science, Scopus, Embase, Google Scholar, and Semantic Scholar databases for the period of January 2000 toDecember 2023.

Inclusion criteria were articles reporting investigations of children younger than 18 years who were diagnosed with NS and would benefit from zinc supplementation compared with a similar control group. The studies were verified according to the PRISMA criteria. In our initial screening we identified 1063 articles. After screening, 25 full-text articles were analyzed. After we applied the inclusion/exclusion criteria, 6 articles (484 patients) were included in the review.

The data considered eligible, regardless of the duration of supplementation, were entered into Review Manager software for analysis using random effects models. Analysis of the causes of heterogeneity revealed that zinc supplementation has shown a beneficial effect on widening the disease-free interval, reducing the number of patients experiencing relapses (relative risk [RR]: 0.70, 95% CI, 0.58 to 0.84, P = .0001; NNT = 5), the mean relapse rate (SMD, -0,41, 95% CI, -0.78 to -0.04, P = .03) and of the need for hospitalization (SMD: -1.35, 95% CI -1.78 to -0.91, P < 00001) depending on the duration of supplementation. In accordance with the Grading of Recommendations Assessment, Development and Evaluation (GRADE) guidelines, we found a medium level of certainty for the interrelationship of zinc supplementation-with reduction in the number of relapses/mean relapses and a low level between zinc supplementation and the reduction in time spent hospitalized.

Zinc supplementation seems to be beneficial in improving the course of pediatric NS. Due to the limited amount of evidence included in the present study, additional studies are needed in order to establish the true size of the effect.

PROSPERO registration No. [CRD42024527895].