TNF and otitis media with effusion: In current study, we found that serum levels of IL-5 (one of the most important TH-2-type cytokines) were significantly higher in children with OME in comparison with those without OME (P=0.009), but that there was no significant difference in serum levels of IL13, IL-4, IFN-γ, or TNF-α between children with and without OME.