Evaluation of BCG Vaccine Immunogenicity in Relation to Vitamin D Status in a Group of Egyptian Children

Background: Vitamin D has an immuomodulatory role in vaccine response and this may be mediated via its action on antigen presenting cells with the most potent effects on dendritic cells. Aim of work: was to determine if there is an association between circulating 25(OH)D concentrations and BCG vaccine cytokine response (interferon gamma) level. Methods: A cross sectional study included 80 infants aged 4 - 9 months from the pediatric outpatient clinic of Al-Zahraa university hospital (40 with normal weight and 40 with underweight). Participants were subjected to history taking, clinical examination, and laboratory investigations, particularly 25 hydroxy vitamin D [25(OH)D] and BCG vaccine-induced interferon gamma (IFN-γ). Results: The study showed that the underweight group had a lower socioeconomic level and higher percentage of breastfeeding compared with the normal weight group. Most infants in our study received vitamin D supplementation (80% and 62.5% in normal and underweight groups, respectively). The average serum level of 25(OH)D was relatively high (>100 ng/ml) in both normal and underweight groups. The mean levels of IFN-γ in response to BCG vaccine were not significantly different between the normal and underweight groups of infants in our study. Also, there was a statistically-significant moderate correlation between serum levels of 25(OH)D and BCG vaccine-induced IFN-γ in both normal (r = 0.58) and underweight (r = 0.64) groups. Conclusion: A good vitamin D status was observed in all studied infants irrespective of their nutritional status and significant correlation with BCG vaccine induced IFN-γ.