Secretory otitis media: microbiology of the middle ear and the nasopharynx.

Specimens for bacterial culture were obtained from 117 children with secretory otitis media (SOM). From the nasopharynx Streptococcus pneumoniae, Haemophilus influenzae, Branhamella catarrhalis and group A streptococci were isolated in 79% of the patients. Of 168 ear exudates, 30 yielded growth (18%) from 26 of the patients (22%). Pneumococcal capsular polysaccharides could not be detected in exudates assayed by counterimmunoelectrophoresis. The recovery rate of bacteria from the ear exudates was significantly higher in patients with positive than with negative nasopharyngeal culture (p less than 0.05). The nasopharyngeal pathogens invading the middle ear in SOM seem to survive there for a period of time and are then replaced by other strains according to the fluctuation of the nasopharyngeal flora where approximately 40% of the strains were eliminated and replaced by other strains over a period of 12 to 13 days.