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Published on: September 11, 2020

Penicillin-resistant Streptococcus pneumoniae in Iran

Jamshid Kohanteb1, Esmaeel Sadeghi

  • 1Department of Medical Microbiology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran. kohanj@sums.ac.ir

Medical Principles and Practice : International Journal of the Kuwait University, Health Science Centre
|December 13, 2006
PubMed
Abstract

Insights

Penicillin resistance in Streptococcus pneumoniae is a growing concern, with approximately one-third of isolates showing nonsusceptibility. This study highlights the prevalence of penicillin-resistant S. pneumoniae in community-acquired infections.

Area of Science:

  • Medical Microbiology
  • Infectious Diseases
  • Antimicrobial Resistance

Background:

  • Streptococcus pneumoniae is a leading cause of community-acquired infections.
  • Penicillin resistance in S. pneumoniae complicates treatment and necessitates surveillance.
  • Understanding regional resistance patterns is crucial for effective antimicrobial stewardship.

Purpose of the Study:

  • To determine the prevalence of penicillin-resistant Streptococcus pneumoniae.
  • To analyze resistance patterns in S. pneumoniae isolated from various clinical specimens in a specific region.

Main Methods:

  • Bacterial isolates: 115 strains of S. pneumoniae from diverse clinical sources (blood, CSF, ear, eye, sinusitis, sputum, pleural fluid).
  • Antimicrobial susceptibility testing: Broth dilution method to determine Minimum Inhibitory Concentration (MIC) for penicillin and other antibiotics.
  • Data analysis: Calculation of resistance and intermediate resistance rates, comparison between sterile and non-sterile sites.

Main Results:

  • Overall nonsusceptibility to penicillin was observed in 33.9% of S. pneumoniae isolates (15.6% resistant, 18.3% intermediately resistant).
  • Penicillin resistance was significantly higher in isolates from sterile sites (60%) compared to non-sterile sites (26.7%).
  • MIC values indicated a wide range of susceptibility for penicillin and other tested antibiotics.

Conclusions:

  • Approximately one-third of S. pneumoniae clinical isolates in this region exhibit nonsusceptibility to penicillin.
  • The high rate of penicillin resistance, particularly from sterile sites, warrants attention for treatment guidelines.
  • Continued monitoring of antimicrobial resistance patterns is essential for public health.

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