Comparison of the antibacterial activities of ampicillin, ciprofloxacin, clarithromycin, telithromycin and quinupristin/dalfopristin against intracellular non-typeable Haemophilus influenzae.
Non-typeable Haemophilus influenzae, which is a cause of disease in the upper and lower respiratory tract, can survive intracellularly in human epithelial cells and macrophages. We studied the in vitro activity of five antibiotics against intracellular non-typeable H. influenzae in human type II alveolar epithelial cells. The eukaryotic cells were loaded with bacteria, and extracellular bacteria were killed by gentamicin. After the cells were washed, antibiotics were added at concentrations of 0.12-64 mg/L for 18 h before the numbers of viable intracellular bacteria were determined. Of the antibiotics tested, ciprofloxacin and quinupristin/dalfopristin were the most potent agents, followed by clarithromycin and telithromycin. Ampicillin was not active against intracellularly localized, non-typeable H. influenzae.
Ahrén
Irini Lazou
IL
Department of Medical Microbiology, University Hospital Malmö, Lund University, S-205 02 Malmö, Sweden.
Karlsson
Eva
E
Forsgren
Arne
A
Riesbeck
Kristian
K
D000667:Ampicillin / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015373:Bacterial Typing Techniques; D002939:Ciprofloxacin / Q000494:pharmacology; D017291:Clarithromycin / Q000494:pharmacology; D006193:Haemophilus influenzae / Q000145:classification / Q000187:drug effects* / Q000302:isolation & purification; D006801:Humans; D007424:Intracellular Fluid / Q000187:drug effects* / Q000382:microbiology*; D048628:Ketolides; D018942:Macrolides; D008826:Microbial Sensitivity Tests / Q000706:statistics & numerical data; D014407:Tumor Cells, Cultured; D014769:Virginiamycin / Q000494:pharmacology
D000900:Anti-Bacterial Agents; D048628:Ketolides; D018942:Macrolides; D014769:Virginiamycin; C062940:quinupristin-dalfopristin; D002939:Ciprofloxacin; D000667:Ampicillin; D017291:Clarithromycin; C106791:telithromycin