Otitis media: antibiotic resistance of causative pathogens and treatment alternatives

A number of studies have indicated a rise in the prevalence of beta-lactamase-producing strains of Haemophilus influenzae and Moraxella catarrhalis and the emergence of antibiotic-resistant strains of Streptococcus pneumoniae. This evolution among the bacterial pathogens most often responsible for otitis media in children has prompted exploration of alternatives to amoxicillin, the traditional first line agent for the management of this infection. A number of alternatives have been identified, including the macrolide clarithromycin and the azalide azithromycin. Both have good activity against beta-lactamase-positive and -negative strains of M. catarrhalis and against some penicillin-resistant strains of S. pneumoniae. Azithromycin, however, is more effective against H. influenzae and its pharmacokinetic characteristics permit once daily dosing for 5 days, therapeutically equivalent to 10 days of treatment with standard antibiotics. The macrolides have demonstrated clinical efficacy comparable with that of amoxicillin and amoxicillin/clavulanate. Excellent activity against the pathogens responsible for bacterial otitis media, a unique pharmacokinetic profile, and established clinical efficacy suggest that azithromycin should be a useful first line treatment for this common childhood infection.