RESUMEN
The beta-lactamases from 403 Moraxella (Branhamella) catarrhalis clinical isolates obtained during 1994-1995 and 1997-1998 U.S. multicenter surveillance studies were characterized by isoelectric focusing. The overall prevalences of the BRO-1 and BRO-2 enzymes among beta-lactamase-positive isolates were estimated to be 97.5 and 2.5%, respectively. The minimum inhibitory concentrations (MICs) of ampicillin for all BRO-2-producing isolates were =1 microg/ml; however, numerous beta-lactamase-positive isolates for which the ampicillin MICs were =1 microg/ml produced the BRO-1 enzyme (88. 1%).
Asunto(s)
Moraxella catarrhalis/enzimología , beta-Lactamasas/metabolismo , Humanos , Focalización Isoeléctrica , Pruebas de Sensibilidad Microbiana , Moraxella catarrhalis/genética , Moraxella catarrhalis/aislamiento & purificación , Estudios Multicéntricos como Asunto , beta-Lactamasas/genéticaRESUMEN
The in vitro activity of ABT-773 was evaluated against Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis isolates. ABT-773 was the most active antimicrobial tested against S. pneumoniae. ABT-773 and azithromycin were equivalent in activity against H. influenzae and M. catarrhalis and more active than either clarithromycin or erythromycin.
Asunto(s)
Antibacterianos/farmacología , Eritromicina/análogos & derivados , Haemophilus influenzae/efectos de los fármacos , Cetólidos , Moraxella catarrhalis/efectos de los fármacos , Streptococcus pneumoniae/efectos de los fármacos , Eritromicina/farmacología , Humanos , Pruebas de Sensibilidad MicrobianaRESUMEN
From November 1, 1997 to April 30, 1998, 726 Moraxella catarrhalis isolates and 1529 Haemophilus influenzae isolates were obtained from 34 medical centres throughout the United States. Rates of beta-lactamase production were 94.6% among M. catarrhalis and 31.1% among H. influenzae strains. Susceptibility rates of M. catarrhalis isolates to selected antimicrobial agents were greater than 99% for amoxycillin-clavulanate, cefixime, cefpodoxime, cefuroxime, cefaclor, loracarbef, clarithromycin, azithromycin, chloramphenicol and tetracycline, 97.8% for cefprozil, 50.4% for trimethoprim-sulphamethoxazole and 28.1% for ampicillin. Of the antimicrobials tested against H. influenzae, the only agents with susceptibility rates below 96% were loracarbef (87.6%), cefprozil (83.4%), cefaclor (82.7%), trimethoprim-sulphamethoxazole (67.3%) and ampicillin (64.7%). The clarithromycin susceptibility rate was 67.4% but this agent was not tested in the presence of its 14-OH metabolite.