The Frequency of Enterotoxin A Genes and its Association with Antimicrobial Resistance among Staphylococcus aureus Isolates from Clinical Specimens from Patients Admitted to Golestan and Imam Khomeini Hospitals in Ahvaz, Iran

Document Type : Original Article


1 Health Research Institute, Infection and Tropical Disease, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.

2 Department of Microbiology, School of Medical, Health Research Institute, Infection and Tropica; Disease, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.


Background and Objectives:Staphylococcus species have higher abundance among isolated isolates from clinical samples. The spices of Staphylococcus aureus which produces enterotoxin A is more viable against host immune defence. The purpose of this study was to assess the relative abundance of entrotoxin A gene and its relation with antimicrobial resistance in isolates of Staphylococcus aureus isolated from clinical samples.
Subjects and Methods: All of the isolates of Staphylococcus aureus from sample of patient sent to Golestan and Imam Khomeini hospital clinical labs, were tested biochemically in order to confirmthe presence of Staphylococcus aureus strains.  Antibiotic resistance of the isolates was assessed by disk diffusion method and PCR method for detection of entrotoxin A gene.
Results: Among 222 isolates of Staphylococcus aureus from different clinical samples, 102 (45.94%) of these isolates had entrotoxin A gene.  This isolates has been highly resistant to the antibiotics such as Ciprofloxacin, methicillin, gentamicin, erythromycin and clindamycin.
Conclusions: The frequency of the Staphylococcus aureus isolates which produces enterotoxin A Gene in Golestan and Imam Khomeini hospitals was high (46.3% and 45.7% Respectively). This samples also have more resistance against antibiotics than the other which has not gene.


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