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Updated: May 13, 2026

Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
14:04

Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria

Published on: May 8, 2013

Identification and Characterization of a High Vancomycin-Resistant Staphylococcus aureus Harboring VanA Gene Cluster

Anahita Dezfulian1, Mohammad Mehdi Aslani, Mahvash Oskoui

  • 1Research Centre of Gastroenterology and Liver Diseases (RCGLD) in Shahid Beheshti University, Tehran, Iran.

Iranian Journal of Basic Medical Sciences
|March 16, 2013
PubMed
Abstract

Insights

High-level vancomycin-resistant Staphylococcus aureus (VRSA) was isolated from a diabetic patient in Iran. This community-acquired VRSA case highlights the need for public health vigilance against emerging antibiotic resistance.

Area of Science:

  • Clinical microbiology
  • Infectious diseases
  • Antimicrobial resistance

Background:

  • Staphylococcus aureus is a frequent cause of human infections.
  • The emergence of vancomycin-resistant Staphylococcus aureus (VRSA) poses a significant challenge for treating methicillin-resistant Staphylococcus aureus (MRSA) infections.

Purpose of the Study:

  • To report the isolation of a high-level VRSA strain.
  • To characterize the genetic basis of vancomycin resistance in the isolated strain.

Main Methods:

  • Isolation of Staphylococcus aureus from a diabetic patient's foot ulcer in Tehran, Iran.
  • Determination of antibiotic susceptibility using CLSI guidelines.
  • Polymerase chain reaction (PCR) amplification and sequencing of the vanA gene cluster.

Main Results:

  • The isolated S. aureus exhibited high-level vancomycin resistance (MIC ≥ 512 µg/ml).
  • The patient's history indicated community transmission of the VRSA isolate.
  • PCR confirmed the presence of vanA, vanR, and vanS genes, with vanA sequencing showing high similarity to Tn1546.

Conclusions:

  • The isolation of community-acquired VRSA, though rare, is a significant public health concern.
  • Increased efforts from public health authorities are necessary to monitor and control the spread of VRSA.

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