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Streptococcus pyogenes strains associated with invasive and non-invasive infections present possible links with emm

Rao Muhammad Abid Khan1, Sana Anwar2, Zaid Ahmed Pirzada1

  • 1Department of Microbiology, University of Karachi, Karachi-75270, Pakistan.

Iranian Journal of Basic Medical Sciences
|May 15, 2020
PubMed
Abstract

Insights

This study reveals distinct Streptococcus pyogenes strains in Pakistan, linking specific emm types and superantigens to infection severity and antibiotic resistance. Understanding these genetic differences is crucial for managing infections.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Genetics

Background:

  • Streptococcus pyogenes is a significant human pathogen causing diverse infections.
  • Limited data exists on emm types and virulence factors of S. pyogenes in Pakistan.

Purpose of the Study:

  • To characterize emm types and superantigen/exotoxin gene profiles of S. pyogenes from Pakistan.
  • To investigate potential links between genetic profiles, infection invasiveness, and antimicrobial resistance.

Main Methods:

  • Collected 89 S. pyogenes strains from various clinical samples.
  • Screened for five superantigen genes (speA, speB, speC, speF, ssa) and emm types.
  • Utilized multiplex PCR for genetic analysis.

Main Results:

  • Identified 34 distinct emm types/subtypes, with emm68 and emm104 being most prevalent.
  • Observed associations between specific emm types, invasive vs. non-invasive infections, and erythromycin resistance.
  • Detected superantigen genes speB (100%), speF (76%), speC (20%), speA (18%), and ssa (15%), with speC and speA linked to invasive infections.

Conclusions:

  • S. pyogenes clones in Pakistan exhibit variations in emm types, superantigens, and antimicrobial resistance.
  • Genetic lineage of S. pyogenes may correlate with infection presentation and severity.
Keywords:
Antibiotic resistanceExotoxinGASInvasive pathogensMIC

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