Microbiology of serous otitis media in children: Correlation with age and length of effusion

The purpose of this study was to correlate the microbiology of serous otiti s media in children with the duration of the condition and the patient's ag e. Aspirates of serous ear fluids from 114 children were examined for aerob ic and anaerobic bacteria. Bacterial growth was noted in 47 patients (41%). Aerobic organisms only were recovered in 27 aspirates (57% of the culture- positive aspirates); anaerobic bacteria only in 7 (15%); and mixed aerobic and anaerobic bacteria in 13 (28%). A total of 83 bacterial isolates were r ecovered, accounting for 1.8 isolates per specimen (1.2 aerobes and 0.6 ana erobe). There were a total of 57 aerobic isolates, including Haemophilus in fluenzae (15 isolates), Streptococcus pneumoniae (13), and Staphylococcus s p (12). Twenty-six anaerobes were recovered, including anaerobic gram-posit ive cocci (10), Prevotella spp (8), and Propionibacterium at acnes (4). The rate of positive cultures (20 of 36; 56%) was higher in patients younger t han 2 years of age than in those older than 2 years of age (27 of 78; 35%). Streptococcus pneumoniae and H influenzae were more often isolated in chil dren younger than 2 years of age and those with effusion for 3 to 5 months, whereas anaerobes were recovered more often in those older than 2 years of age and those with effusion for 6 to 13 months. These data illustrate the effects of the length of effusion and age on the recovery of aerobic and an aerobic bacteria in serous otitis media.