Serum Inflammatory Cytokines and Vitamin A in Nigerian Children with Community-Acquired Pneumonia: Association with Severity and Outcome

Abstract

AbstractObjective Pneumonia is an acute inflammation of the lung parenchyma caused by microbial agents. The role of inflammatory mediators and modulators like vitamin A in childhood pneumonia in developing countries is poorly explored. The aim of this study is to determine the relationship between serum vitamin A and inflammatory cytokines (i.e., proinflammatory interleukins [IL]-1β, -2, -3, -6, -8, -12, and -17 and anti-inflammatory IL-4, -10, -11, and -13) in Nigerian children with community-acquired pneumonia (CAP) and relate these to pneumonia severity and length of hospital stay (LOS).Methods Children aged 2 months to 14 years with World Health Organization (WHO) defined CAP and age and sex-matched controls were recruited over a 12-month period. Relevant data, serum cytokines, and vitamin A (assayed using chromatography method) were compared between the two groups, and between those with severe and nonsevere pneumonia. Relationships between serum vitamin A, cytokines, and LOS were also determined.Results One hundred and thirty-two children (66 each for CAP and controls; M: F = 1.8:1) were recruited and 17 (12.9%) were vitamin-A deficient. Of the 66 with CAP, 52 (78.8%) had severe pneumonia. Serum proinflammatory cytokines (IL-6, -8, -12, and -17) and anti-inflammatory cytokines (IL-4 and -11) were higher in children with CAP compared with controls. In under-five age group, lower serum IL-4 and vitamin A were associated with severe CAP. Vitamin-A deficient children with CAP had lower proinflammatory cytokines (IL-1β, IL-2, -3, -12, and -17) and anti-inflammatory cytokine IL-4 than vitamin A sufficient ones. IL-6 and IL-8 correlated positively with LOS.Conclusion CAP is associated with elevated serum proinflammatory cytokines and possible resultant higher need of antioxidants properties of vitamin A in severe cases. Vitamin A may be more important to ameliorate the acute inflammatory processes in Nigerian children with severe than nonsevere pneumonia.