Antibiotic-sensitivity of Moraxella catarrhalis isolated from clinical materials in 1997-1998

Moraxella catarrhalis (M. catarrhalis) may normally be found in the upper respiratory tract. This bacterium, however, may cause infections such as acute otitis media, sinusitis, conjunctivitis, bronchitis chronica, pneumonia, endocarditis, septicaemia and meningitis. Haemophilus influenzae, Streptococcus pneumoniae and M. catarrhalis were the main causative agents responsible for respiratory tract infections. The major resistance problems associated with these species are those which cause resistance to beta-lactams. beta-lactamase was produced by > 80% M. catarrhalis strains. The susceptibility to ampicillin, amoxicillin/clavulanic acid, cefuroxime, erythromycin, ciprofloxacin was tested in 137 M. catarrhalis strains. All the strains resistant to ampicillin produced beta-lactamase and were sensitive to amoxicillin/clavulanic acid. For M. catarrhalis, the most active antimicrobials included cefuroxime (99%), ciprofloxacin (99%) and erythromycin (93%).