Effect of inhibitor of tumor necrosis factor-alpha on experimental otitis media with effusion

Tumor necrosis factor (TNF)-alpha is important in the pathogenesis of otiti s media with effusion COME), The purpose of this study was to determine the effect of TNF-alpha antagonist on the outcome of lipopolysaccharide (LPS)- induced OME in rats. Otitis media was induced by injecting Pseudomonas aeru ginosa LPS transtympanically. Another (combination) group was pretreated wi th TNF-a antagonist, soluble TNF receptor type I (sTNF RI), before transtym panic injection of LPS. Saline and phosphate -buffered saline solutions wer e used as controls. Twelve hours after the transtympanic injection, otoscop ic examination and aspiration of middle ear effusion (MEE) were done. The t emporal bones in each group were examined histopathologically, and the vasc ular permeability of the middle ear mucosa was measured by the Evans blue v ital dye technique. In the LPS and combination groups, MEE developed in 90% and 0% of ears, respectively. The combination group showed less inflammati on, less mucosal thickening, and significantly decreased vascular permeabil ity as compared to the LPS group. Transtympanic administration of sTNF RI a ppears to suppress the development of LPS-induced OME, This study suggests that TNF-alpha antagonist, along with antibiotics, may have an adjunctive r ole in the future treatment of MEE.