Antimicrobial activity and spectrum of sparfloxacin tested against erythromycin-resistant Streptococcus pneumoniae isolates.
Recognition of a worldwide increase of penicillin-resistant Streptococcus pneumoniae and cross-resistance to other classes of antimicrobials have placed a great urgency on the need for new antimicrobial agents. Sparfloxacin, a novel pyridone carboxylic acid fluoroquinolone derivative was evaluated and compared to six other compounds for antimicrobial activity against erythromycin-resistant pneumococci (50 strains). The Etest susceptibility testing method was used to inoculate Mueller-Hinton agar supplemented with 5% sheep blood. There was extensive cross-resistance between erythromycin, clarithromycin (94%), and azithromycin (100%), but no cross-resistance was detected between macrolides/azalides and sparfloxacin (all strains susceptible at < or = 1.0 mu g/ml). Sparfloxacin (MIC90, 1 mu g/ml) was four-fold more active than ciprofloxacin and ofloxacin (MIC90, 4 mu g/ml). Sparfloxacin appears to possess excellent in vitro activity against erythromycin-resistant S. pneumoniae that were often highly resistant to beta-lactams, and further studies are recommended to investigate its in vivo efficacy against these multi-resistant organisms.
Barrett
M S
MS
Department of Pathology, University of Iowa College of Medicine, Iowa City, USA.
Jones
R N
RN
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000890:Anti-Infective Agents / Q000494:pharmacology*; D004352:Drug Resistance, Microbial; D004917:Erythromycin / Q000494:pharmacology*; D024841:Fluoroquinolones; D008826:Microbial Sensitivity Tests; D015363:Quinolones / Q000494:pharmacology*; D013296:Streptococcus pneumoniae / Q000187:drug effects*
D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D015363:Quinolones; D004917:Erythromycin; C061363:sparfloxacin