Microbiological studies of the bacterial flora of the external auditory canal in children

The aerobic and anaerobic bacterial flora of the external auditory canal (EAC) was studied in 72 children. Aerobes only were isolated in 58 patients (80%) and anaerobic bacteria only in 2 (3%). Mixed aerobic and anaerobic isolates were recovered in 12 cases (17%). There were 122 aerobic and 15 anaerobic isolates accounting for 1.7 aerobes and 0.2 anaerobes per specimen. The most common aerobic isolates were Staphylococcus epidermidis (56 isolates), alpha hemolytic streptococcus (13) and Pseudomonas aeruginosa (8). The two anaerobic organisms recovered were Proprionibacterium acnes (13 isolates) and Peptococcus sp. (2). These findings demonstrate the polymicrobial bacterial flora of EAC in children where aerobic facultative and anaerobic bacteria are part of the normal flora.