Relationship of Endotoxin to Tumor Necrosis Factor–α and Interleukin-1β in Children with Otitis Media with Effusion

Abstract

Sixty-five middle ear effusions and paired sera from 41 children with chronic otitis media with effusion were assayed for endotoxin and for tumor necrosis factor–α (TNF-α) and interleukin-1β (IL-1β) in order to establish whether a correlation exists between the concentrations of endotoxin and of these cytokines. Endotoxin concentration was determined by means of a chromogenic limulus amebocyte lysate assay, and the cytokine concentration by means of a quantitative enzyme-linked immunosorbent assay. Forty percent of the effusions had detectable levels of endotoxin, with a mean concentration of 2.9 ± 7.8 endotoxin units per milligram of total protein. The mean concentration of TNF-α was 1.24 ± 3.1 pg/mg total protein, and that of IL-1β was 18.79 pg/mg total protein. A strong, statistically significant correlation exists between the concentrations of endotoxin and TNF-α (r =.89) and IL-1β (r =.72). The data indicate that endotoxin may contribute to the pathogenesis of chronic otitis media with effusion by stimulating the sustained production of TNF-α and IL-1β in the middle ear.