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Published on: September 25, 2014

Antimicrobial susceptibility patterns of Streptococcus pneumoniae in Mexico

Francisco Quiñones-Falconi1, Juan José Calva, Yolanda López-Vidal

  • 1Servicio de Microbiología Clínica, Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico.

Diagnostic Microbiology and Infectious Disease
|May 12, 2004
PubMed

Insights

Over half of Streptococcus pneumoniae isolates showed penicillin resistance, indicating a higher likelihood of multidrug resistance. Susceptibility to newer agents like amoxicillin/clavulanate remains high.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Antimicrobial Resistance

Background:

  • Community-acquired respiratory infections (CARIs) pose a significant public health challenge.
  • Streptococcus pneumoniae is a primary pathogen causing CARIs.
  • Antimicrobial resistance in S. pneumoniae necessitates ongoing surveillance.

Purpose of the Study:

  • To evaluate the antimicrobial susceptibility patterns of Streptococcus pneumoniae isolates from CARIs in Mexico.
  • To determine the prevalence of resistance to beta-lactam and non-beta-lactam agents.
  • To assess the correlation between penicillin nonsusceptibility and multidrug resistance.

Main Methods:

  • Broth microdilution method used for susceptibility testing.
  • Analysis of 315 pneumococcal isolates collected between 1995 and 2001.
  • Evaluation of resistance to 14 antimicrobial agents.

Main Results:

  • Fifty-two percent of isolates were nonsusceptible to penicillin.
  • Penicillin-nonsusceptible isolates showed higher resistance to other antimicrobial classes.
  • Over 90% susceptibility observed for amoxicillin/clavulanate, ceftriaxone, levofloxacin, and gatifloxacin.

Conclusions:

  • Reduced penicillin susceptibility is a marker for multidrug resistance in S. pneumoniae.
  • In vitro testing is crucial for guiding chemotherapy choices.
  • Effective treatment options include amoxicillin/clavulanate, ceftriaxone, levofloxacin, and gatifloxacin.

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