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Streptococcus pneumoniae: susceptibility to penicillin and moxifloxacin

Flávia Rossi1, Maria Renata Gomes Franco, Heleni Mota de Pina Rodrigues

  • 1Laboratório de Microbiologia, Hospital das Clinicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brasil. frossi@hcnet.usp.br

Jornal Brasileiro De Pneumologia : Publicacao Oficial Da Sociedade Brasileira De Pneumologia E Tisilogia
|March 13, 2012
PubMed
Abstract

Insights

Streptococcus pneumoniae isolates showed high susceptibility to penicillin and moxifloxacin. These findings, focusing on non-meningitis infections, differ from international reports and suggest updated resistance breakpoints are needed.

Area of Science:

  • Medical Microbiology
  • Infectious Diseases
  • Antimicrobial Resistance

Background:

  • Streptococcus pneumoniae is a significant pathogen.
  • Understanding antimicrobial susceptibility is crucial for effective treatment.
  • Previous reports indicate varying resistance patterns globally.

Purpose of the Study:

  • To determine the minimum inhibitory concentrations (MICs) of parenteral penicillin and moxifloxacin.
  • To assess the susceptibility of Streptococcus pneumoniae strains isolated from a hospital center.

Main Methods:

  • Prospective in-vitro study of 100 S. pneumoniae isolates.
  • Isolates collected from patients between 2008-2010.
  • Penicillin and moxifloxacin susceptibility tested using E-test with updated standards.

Main Results:

  • All 100 isolates were fully susceptible to parenteral penicillin.
  • 99% of S. pneumoniae strains were susceptible to moxifloxacin; one showed intermediate resistance (MIC = 1.5 µg/mL).
  • Susceptibility to other antibiotics like amoxicillin, ampicillin, cephalosporins, and ertapenem was also observed.

Conclusions:

  • High susceptibility rates to penicillin and moxifloxacin were observed in non-meningitis S. pneumoniae isolates.
  • These findings contrast with some international reports.
  • Updated breakpoints are recommended for non-meningitis isolates to guide therapy and predict outcomes.

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