Dataset Information

Bactericidal activity of besifloxacin against staphylococci, Streptococcus pneumoniae and Haemophilus influenzae.

ABSTRACT:

Objectives

Besifloxacin is a novel fluoroquinolone that was recently approved for topical treatment of bacterial conjunctivitis. The compound was shown to be active in vitro against a broad spectrum of bacteria, including isolates resistant to other antibacterials. Here, the bactericidal activity of besifloxacin was evaluated against the most common bacterial conjunctivitis pathogens.

Methods

MIC, MBC and time-kill experiments with besifloxacin and comparators were performed according to CLSI guidelines. Quinolone resistance-determining regions (QRDRs) were sequenced using standard PCR-based techniques.

Results

MIC and MBC data indicated that besifloxacin was the most potent fluoroquinolone tested against Staphylococcus aureus (n = 30), Staphylococcus epidermidis (n = 15) and Streptococcus pneumoniae (n = 35), while all fluoroquinolones were highly active against Haemophilus influenzae (n = 40). Besifloxacin MBC:MIC ratios were < or = 4 for 97.5% of all isolates tested (n = 120). All fluoroquinolones tested, as well as tobramycin, were bactericidal, while azithromycin was bactericidal against S. pneumoniae and H. influenzae, but bacteriostatic against the staphylococci. Time-kill assays with all four species showed that besifloxacin caused > or = 1000-fold killing within 2 h for 11 of 12 isolates. Only one isolate treated with moxifloxacin and three ciprofloxacin-treated isolates achieved the same level of bactericidal activity under the same conditions. Unlike the comparator fluoroquinolones, besifloxacin maintained a high potency and bactericidal activity even against strains that contained multiple mutations in the genes encoding DNA gyrase and topoisomerase IV.

Conclusions

Overall, besifloxacin demonstrated rapid bactericidal activity against the four major human pathogens tested here, including isolates that showed in vitro resistance to other fluoroquinolones, beta-lactams, macrolides or aminoglycosides.

SUBMITTER: Haas W

PROVIDER: S-EPMC2882870 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature

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Publications

Bactericidal activity of besifloxacin against staphylococci, Streptococcus pneumoniae and Haemophilus influenzae.

Haas Wolfgang W Pillar Chris M CM Hesje Christine K CK Sanfilippo Christine M CM Morris Timothy W TW

The Journal of antimicrobial chemotherapy 20100430 7

<h4>Objectives</h4>Besifloxacin is a novel fluoroquinolone that was recently approved for topical treatment of bacterial conjunctivitis. The compound was shown to be active in vitro against a broad spectrum of bacteria, including isolates resistant to other antibacterials. Here, the bactericidal activity of besifloxacin was evaluated against the most common bacterial conjunctivitis pathogens.<h4>Methods</h4>MIC, MBC and time-kill experiments with besifloxacin and comparators were performed accor ...[more]

PMID: 20435780

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Dataset Information

Bactericidal activity of besifloxacin against staphylococci, Streptococcus pneumoniae and Haemophilus influenzae.

Objectives

Methods

Results

Conclusions

Publications

Bactericidal activity of besifloxacin against staphylococci, Streptococcus pneumoniae and Haemophilus influenzae.

Similar Datasets

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