Neutrophil elastase in ear discharges of chronic suppurative otitis media

Abstract

Neutrophil elastase (NE) levels in ear discharges from 15 chronic suppurative otitis media (CSOM) patients were measured by sensitive sandwich ELISA in order to discuss roles of NE in the prolonged middle ear inflammation of CSOM. Levels of NE complexed with α₁-antitrypsin were 13.7μg/ml in CSOM and 7.8μg/ml in middle ear effusions (MEE) from chronic otitis media with effusion (OME). However, total NE levels in CSOM (162μg/ml) was significantly higher than that in chronic OME (16.5μg/ml). These results indicate that majority of NE in ear discharges from CSOM patients is occupied by free NE. Total NE levels in CSOM were not parallel to the results of cytological study, suggesting that free NE could contribute to the inflammatory reaction taken place in the middle ear mucosa even after cell lysis of neutrophils.