Aspiration of exudate through an open perforation was performed in 183
patients with chronic otitis media. The pus was cultured aerobically
and anaerobically. Aerobes only were isolated from 71 patients (39%);
20 patients (11%) had only anaerobes; and 91 patients (50%) had both a
erobes and anaerobes. Only 1 specimen had no growth. There were 259 ae
robic isolates. Pseudomonas aeruginosa was recovered from 68 patients.
Other aerobes commonly recovered included Staphylococcus aureus and K
lebsiella pneumoniae. There were 178 anaerobic isolates. Only anaerobi
c gram-positive cocci were isolated in 20 instances. Sixty-three Bacte
roides isolates were recovered, including 12 Bacteroides fragilis grou
p and 21 Bacteroides melaninogenicus.