Bacteria in the middle ear and ear canal of patients with secretory otitis media and with non-inflamed ears.

Aerobic and anaerobic semiquantitative bacteriological cultures were taken from 110 mucoid middle ear effusions and the respective ear canals of 74 patients with secretory otitis media (SOM). Additionally, mucosal pieces from 20 non-inflamed middle ears and swabs from the ear canals were cultured similarly. Bacteria were found in 35 effusions and 65 ear canals with SOM; in both sites the most frequent species were S. epidermidis and S. aureus, and the species distributions were not significantly different in the sites. Ten effusions grew bacteria not culturable in the respective ear canal samples. Anaerobes were found in one effusion only. Nine non-inflamed middle ears revealed bacteria; the species distribution was no different from SOM, and four of the bacteria were not found in the ear canal of the same ear. In conclusion, there may be bacteria in the middle ear in the absence of inflammation and in SOM, but the role of viable bacteria seems to be nil in an established secretory otitis media.