High Silent Prevalence of Zinc Deficiency and Impaired Immunity in Children Under Five Years of Age Admitted to a Regional Referral Hospital in Uganda

Abstract

Introduction: Zinc deficiency (ZnD) impairs the development of acquired immunity and contributes to growth failure in children under five years of age. However, the prevalence of ZnD and its association with immunity in this age group in Uganda have not been well explored. This study aimed to determine the prevalence of ZnD and explore the associations between low serum zinc levels and total white blood cell count, differential cell counts, and levels of IL-1 and IL-2 in children aged 12 to 59 months. Methods: In this cross-sectional study, we enrolled children aged 12 to 59 months upon admission to the pediatrics ward of Masaka Regional Referral Hospital (MRRH), located in Masaka City, Southern Uganda. Anthropometric measurements were taken and interpreted using the WHO growth standards charts for age and sex. Whole blood cell counts, serum zinc levels, CRP, and IL-2 and IL-4 were measured. Student’s t-test, Mann-Whitney test, and correlation coefficients were used to assess relationships between variables. Results: A total of 40 children (mean age 27.8 (SD 10.6) months; 50% boys) were enrolled. Nearly a third (13/40) of the children were malnourished (22.5% stunted and 12.5% wasted), and 82.5% had anemia (Hb< 11.0 g/dL). The prevalence of ZnD was 40.6%. Serum zinc levels showed a positive correlation with total white blood cell count (rs = 0.41, p = 0.02) and lymphocyte count (r s = 0.43, p = 0.01). However, no association was found between ZnD and levels of IL-2 or IL-4. Conclusions: The study revealed a high prevalence of ZnD, with serum zinc levels correlating with both total white blood cell and T cell counts, but not with IL-2 levels, in children under five years of age at the time of admission. We recommend the routine inclusion of ZnD assessment and treatment in the care of sick children in the region. Additionally, a larger multicenter longitudinal study is needed to further evaluate the association between malnutrition and health outcomes in this age group.