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Activity of telithromycin compared with seven other agents against 1039 Streptococcus pyogenes pediatric isolates

B Bozdogan1, P C Appelbaum, L M Kelly

  • 1Department of Pathology, Hershey Medical Center, 500 University Dr., Hershey, PA 17033, USA.

Clinical Microbiology and Infection : the Official Publication of the European Society of Clinical Microbiology and Infectious Diseases
|August 20, 2003
PubMed

Insights

Pediatric Streptococcus pyogenes isolates showed high susceptibility to common antibiotics. However, macrolide resistance, primarily due to specific genetic mechanisms, was notable in several Central and Eastern European countries.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Public Health

Background:

  • Streptococcus pyogenes (group A Streptococcus) is a significant pediatric pathogen.
  • Antibiotic resistance in S. pyogenes is a growing public health concern, impacting treatment efficacy.
  • Surveillance of antibiotic resistance patterns is crucial for guiding clinical practice.

Purpose of the Study:

  • To investigate the antibiotic susceptibility patterns of pediatric Streptococcus pyogenes isolates in Central and Eastern Europe.
  • To identify the prevalence and genetic basis of macrolide resistance in these isolates.

Main Methods:

  • Antimicrobial susceptibility testing was performed on 1039 pediatric S. pyogenes isolates.
  • Molecular methods were used to characterize the genetic mechanisms of erythromycin resistance.
  • Isolates were sourced from Bulgaria, Croatia, Czech Republic, Hungary, Latvia, Lithuania, Poland, Romania, Slovakia, and Slovenia.

Main Results:

  • All isolates were susceptible to penicillin G, levofloxacin, and quinupristin-dalfopristin.
  • High susceptibility rates were observed for telithromycin, erythromycin, azithromycin, clarithromycin, and clindamycin.
  • Macrolide resistance was most prevalent in Slovakia (25%), Czech Republic (17.3%), and Croatia (15.8%), with 9.7% overall resistance.
  • Erythromycin resistance was mainly attributed to erm(B) or erm(A) methylases (72.3%) or mef(A) efflux pump (25.7%).
  • One isolate exhibited dual resistance mechanisms involving 23S rRNA and ribosomal protein L22 alterations.

Conclusions:

  • Pediatric S. pyogenes isolates in the study region remain largely susceptible to penicillin and other key antibiotics.
  • The prevalence of macrolide resistance, driven by specific genetic determinants, warrants continued monitoring, particularly in certain countries.
  • Understanding resistance mechanisms is vital for effective management of streptococcal infections.

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