Immune complexes in middle ear effusions

Abstract

Middle ear effusions (MEE) from 20 patients (ages 3 to 14 years) with secretory otitis media were examined. The soluble immune complex was determined at higher level in MEE than the corresponding sera using C1_q solid-phase ELISA. The purulent type MEE contained higher level of immune complex compared with the serous type MEE. Free bacterial capsular polysaccharide antigens were identified by counterimmunoelectro-phoresis (CIE). The advantage of the CIE method lies in its ease of performance, rapidity and specificity. The sensitivity of the procedure is high and it is possible to detect 0.03 to 0.50 μg of polysaccharide antigens per milliliter . This analysis revealed Haemophilus influenzae in 3.8% and Streptococcus pneumoniae in 7.7% in MEE, respectively. Heating of the samples to disrupt the immune complexes increased the frequency of positive samples to 23.0% and 23.0%, respectively. Although there was little direct evidence implicating immunological processes in the pathogenesis of secretory otitis media, the circumstantial evidence found in this study suggested that there was an accumulation of the immune complexes in the middle ear environment and the immune complex might mediate an adverse effect.