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Published on: March 2, 2020

[Molecular epidemiology of fluoroquinolone-resistant Streptococcus pneumoniae in Japan]

Shin-ichi Yokota1, Kiyoshi Sato, Shigeru Yoshida

  • 1Department of Microbiology, Sapporo Medical University School of Medicine.

Kansenshogaku Zasshi. the Journal of the Japanese Association for Infectious Diseases
|June 24, 2004
PubMed

Insights

Fluoroquinolone resistance in Streptococcus pneumoniae is emerging in Japan, with mutations found in key bacterial genes. This resistance appears to develop sporadically, primarily in older adults.

Area of Science:

  • Microbiology
  • Genetics
  • Pharmacology

Context:

  • Emergence of fluoroquinolone resistance in Streptococcus pneumoniae is a growing global health concern.
  • Surveillance of antimicrobial resistance is crucial for public health, especially in Japan.
  • Previous studies have documented fluoroquinolone resistance in Streptococcus pneumoniae, but specific genetic mechanisms and clonal spread patterns require further investigation.

Purpose:

  • To investigate the prevalence and genetic basis of fluoroquinolone resistance in Streptococcus pneumoniae clinical isolates from Hokkaido, Japan.
  • To analyze the mutation patterns in target genes (parC, parE, gyrA, gyrB) associated with fluoroquinolone resistance.
  • To determine the clonal relatedness of resistant strains using random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR).

Summary:

  • Eleven fluoroquinolone-resistant Streptococcus pneumoniae strains were identified from 670 clinical isolates collected between 1999 and 2003 in Hokkaido, Japan.
  • All resistant strains showed resistance to ciprofloxacin and levofloxacin, with most also resistant to tosufloxacin, sparfloxacin, and gatifloxacin.
  • Genetic analysis revealed mutations in gyrA, parC, or parE genes, with higher resistance linked to mutations in two genes. RAPD-PCR indicated ten independent clones, suggesting sporadic development of resistance rather than clonal spread.

Impact:

  • The findings highlight the sporadic emergence of fluoroquinolone resistance in Streptococcus pneumoniae, driven by genetic mutations rather than widespread dissemination of resistant clones.
  • The study observed a higher prevalence of resistant strains in adults, particularly those over 60 years old, suggesting age-related susceptibility or exposure patterns.
  • This research contributes to understanding the evolving landscape of antibiotic resistance and informs strategies for antimicrobial stewardship, particularly concerning fluoroquinolone use in different age groups.

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