Abstract
Objectives
We investigated serum cytokine levels in pediatric patients with pandemic influenza H1N1 2009 virus (H1N1) infectionβpneumonia and in pediatric patients with pneumonia but without H1N1 infection, and examined correlations between cytokine levels and clinical/laboratory findings.
Methods
Fiftyβseven cases of infection by H1N1 were confirmed by RTβPCR and enrolled. Of these 57 cases, 26 had a severe H1N1 infection (group 1), and 31 had a mild H1N1 infection (group 2). Sera from 18 cases with pneumonia without H1N1 infection (group 3) were used as controls. The serum levels of 10 cytokines were determined by multiplex assay.
Results
The serum levels of IFNβΞ±, ILβ6, and IPβ10 were significantly higher in H1N1 infected cases than in group 3, and levels of ILβ6 and IPβ10 were significantly higher in group 1 than in group 2. The level of ILβ10 was significantly higher in groups 1 and 3 than in group 2. However, levels of IFNβΞ³ and ILβ17 were not significantly different between the three groups. ILβ1Ξ², ILβ4, and MIPβ1Ξ± were not detectable in most patients. IPβ10 and ILβ6 levels were found to show negative correlations with lymphocyte count and oxygen saturation.
Conclusions
We found higher levels of cytokines (IFNβΞ±, ILβ6, IPβ10) of innate immunity than those of acquired immunity in pediatric H1N1 infection. Of the cytokines found to be increased in cases with H1N1 infection, IPβ10 and ILβ6 were found to be correlated with disease severity (lymphopenia and hypoxia). IPβ10 and ILβ6 may be important markers in pediatric H1N1 infection. Pediatr Pulmonol. 2011; 46: 1233β1239. Β© 2011 Wiley Periodicals, Inc.