Aerobic and anaerobic bacteria in chronic suppurative otitis media. A quantitative study

The aerobic and anaerobic bacterial flora of middle ear exudate (MEE) of 47 consecutive patients with chronic suppurative otitis media were studied using a quantitative bacteriological technique under strictly anaerobic conditions. Specimens from the external auditory canal (EAC) and the nasopharynx (NP) were obtained in order to correlate the bacterial findings with those of the MEE. Aerobic bacteria were invariably present in the MEE, the predominant aerobic species being Pseudomonas, found in 32%. Anaerobic bacteria were found in 45%: most anaerobes (55%) were cocci, 33% were of the Bacteroides species. The flora of the MEE correlated well with the bacteriological findings in the EAC cultures. In contrast, most organisms isolated from the NP represented the normal skin flora or were common respiratory pathogens.