Bacteriology of otitis media with effusion

A study was undertaken to evaluate the prevalence and antibiotic susceptibility of bacteria present in the middle ear of patients with otitis media with effusion. Middle ear effusions (MEE), nasopharyngeal and throat swabs were obtained at operation and cultured for aerobic and anaerobic bacteria. Two hundred and fifty-nine effusions were obtained from 152 subjects examined. Haemophilus influenzae was isolated from 32 (12.3 per cent) effusions, Streptococcus pneumoniae from seven (2.7 per cent), Staphylococcus aureus from seven (2.7 per cent), Branhamella catarrhalis from one (0.4 per cent)--Group A beta haemolytic streptococci from one (0.4 per cent) and Staphylococcus epidermidis from three (1.9 per cent). The occurrence of respiratory pathogens in MEE reflected their prevalence in the upper respiratory tract. Significantly fewer children who had received antibiotics prior to surgery had organisms present in the MEE. Eight and a half per cent of H. influenzae and 64 per cent of B. catarrhalis were resistant to ampicillin. The present study confirms that bacteria are present in the middle ear in a significant number of patients with otitis media with effusion.