Identification and Characterization of a High Vancomycin-Resistant Staphylococcus aureus Harboring VanA Gene Cluster Isolated from Diabetic Foot Ulcer


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

2 Department of Microbiology, Institute Pasteur of Iran, Tehran, Iran


Staphylococcus aureus is a common cause of human infection, and emergence of vancomycin-resistance S. aureus  is a great concern for treatment of methicillin-resistant S. aureus,(MRSA) in recent years (MRSA). Here, we report the isolation of high-level VRSA.
Materials and Methods
S. aureus was isolated from foot ulcer of a diabetic woman in Tehran, Iran. Antibiotic susceptibility was determined according to CLSI guidelines. VanA gene cluster PCR was carried out and PCR amplicon of vanA was sequenced.
S. aureus had high-level vancomycin-resistant (MIC 512 ≥ µg/ml). Patient's history revealed that VRSA isolate was acquired through community transmission. Only vanA, vanR and vanS genes were amplified in our isolate. Sequencing revealed that the vanA sequence had high similarity to the vanA sequence of Tn1546.
Although VRSA infection continues to be rare, isolation of community–acquired VRSA is a significant issue and it needs the efforts of public health authorities.


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