Antimicrobial susceptibility of bacterial isolates from patients presenting with ear, nose and throat (ENT) infections in the German community healthcare setting.

Empiric initial antibiotic therapy of bacterial infections is based primarily upon the susceptibility of the most common causative pathogens. The purpose of this study was to provide susceptibility data on six bacterial species known to cause ear, nose and throat (ENT) infections. A total of 1066 isolates collected during a nationwide laboratory-based surveillance study were analysed. All Streptococcus pyogenes isolates were penicillin (PEN)-susceptible, indicating that natural penicillins can still be recommended as the first-line treatment for group A streptococcal tonsillopharyngitis. Of the S. pneumoniae isolates, 92.9% were PEN-susceptible and of the Haemophilus influenzae isolates, 89.7% were amoxicillin-susceptible, retaining aminopenicillins as the first-line treatment for acute otitis media (AOM) and acute rhinosinusitis (ARS), in case antibiotic therapy is considered. In contrast, cefuroxime axetil seems less likely to be suitable for the treatment of AOM or ARS, as all Moraxella catarrhalis and >99% of the H. influenzae isolates were categorised as intermediate or resistant. The susceptibility rates of Pseudomonas aeruginosa were 97-100% for the drugs tested, except for the fluoroquinolones (87.6%). Overall, bacterial isolates from outpatients presenting with ENT infections showed low frequencies of resistance in Germany. However, given the emergence of multidrug resistance to standard antibiotics in Escherichia coli and other pathogens, inappropriate use of broad-spectrum antibiotics for the treatment of ENT infections has to be avoided.