Bacteriological study of acute otitis media in children. Therapeutic consequences

One hundred children presenting with acute otitis media underwent a bacteriological study of otitis exudate over a 18 month period. The bacteria found were as follows: Streptococcus pneumoniae (24), Haemophilus influenzae (19), Staphylococcus aureus (12), Streptococcus pyogenes (7), Branhamella catarrhalis (3), and 18 Gram negative bacilli (including 7 Pseudomonas aeruginosa and 11 enterobacteriaceae). One pathogenic bacterium was isolated in 56 cases, 2 or more in 12 cases and none in 32 cases. In the age categories 0-1 year (47 cases) and 1-3 years (31 cases), S. pneumoniae and H. influenzae were the main organisms found, followed by S. pyogenes in children older than 3 years (22 cases). With respect to the antibiotics used for treating otitis, 5/22 S. pneumoniae and 4/17 H. influenzae were erythromycin resistant (9/17 had an intermediate susceptibility) and 7/19 H. influenzae and 1/17 S. pneumoniae were cotrimoxazole resistant. None of the S. pneumoniae and 2/19 H. influenzae were ampicillin resistant. These 2 H. influenzae and 2/3 B. catarrhalis were beta-lactamase producers. They were sensitive to the combination of amoxicillin with clavulanic acid.