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Activity of ceftibuten, cefaclor, azithromycin, clarithromycin, erythromycin and telithromycin against Streptococcus

Lorenzo Drago1, Sandro Ripa, Claudia Zampaloni

  • 1Department of Molecular Cellular Animal Biology, University of Camerino, Italy.

Chemotherapy
|August 10, 2005
PubMed
Abstract

Insights

Oral cephalosporins like ceftibuten and cefaclor demonstrate superior antimicrobial activity against Streptococcus pyogenes. Telithromycin offers a viable alternative, though less effective against constitutively macrolide-lincosamide-streptogramin B resistant strains.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Antimicrobial Resistance

Background:

  • Increasing prevalence of macrolide-resistant Streptococcus pyogenes strains globally.
  • Macrolide resistance in S. pyogenes is mediated by various genes, conferring differential resistance to macrolides, lincosamides, and streptogramin B (MLS).

Purpose of the Study:

  • To compare the in vitro antimicrobial activity of several antibiotics against Streptococcus pyogenes.
  • To evaluate the efficacy of different antibiotic classes against macrolide-resistant S. pyogenes phenotypes.

Main Methods:

  • Broth microdilution method used to test azithromycin, clarithromycin, erythromycin, ceftibuten, cefaclor, and telithromycin against 287 S. pyogenes strains.
  • Phenotypic and genotypic characterization of erythromycin resistance, including M-typing via PCR.

Main Results:

  • Ceftibuten and cefaclor exhibited the strongest antimicrobial activity.
  • Telithromycin displayed higher Minimum Inhibitory Concentration (MIC) values against constitutively MLS (cMLS)-resistant strains compared to other phenotypes.

Conclusions:

  • Oral cephalosporins maintain optimal activity against S. pyogenes.
  • Telithromycin is a suitable alternative antimicrobial, demonstrating good efficacy except in cases of cMLS resistance.

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