Association Between Vitamin A Deficiency and Pneumonia Severity in Hospitalized Children Aged Six Months to Five Years

Background: Vitamin A supports respiratory immunity, but circulating retinol also falls during infection, so its relationship with pneumonia severity is uncertain.Objective: This study aimed to examine the association between low serum vitamin A at admission and pneumonia severity in hospitalized children aged six months to five years.Methods: In this prospective, hospital-based cross-sectional study with consecutive enrollment, 70 children admitted with pneumonia to a tertiary hospital in Kanpur, India, between December 2024 and May 2026 had serum vitamin A measured by high-performance liquid chromatography at admission.Low serum vitamin A was defined as <20 µg/dL.Severe pneumonia followed World Health Organization/Integrated Management of Childhood Illness (WHO/IMCI)-based criteria.Analyses included Fisher's exact test, prevalence and odds ratios, and exploratory Firth penalized logistic regression.Results: Low serum vitamin A was present in 19 of 70 children (27.1%).Severe pneumonia occurred in 17 of 19 (89.5%) children with low values versus 15 of 51 (29.4%) with normal values (prevalence ratio=3.04;95% confidence interval (CI)=1.94-4.78;odds ratio=20.4;95% CI=4.18-99.45).The adjusted odds ratio in an exploratory model was 16.7 (95% CI=3.07-91.01).Excluding 12 children with severe acute malnutrition, all of whom also had hypoxemia, gave an odds ratio of 9.69 (95% CI=1.78-52.77).Conclusion: Low serum vitamin A measured during acute pneumonia was strongly associated with severe pneumonia.Because retinol falls with inflammation and malnutrition was common, preexisting deficiency cannot be inferred; prospective studies with inflammatory markers and measurements before infection are needed.