The prevalence of antibiotic resistance and exfoliative toxin A gene in Staphylococcus aureus strains isolated from patients and healthy individuals

Abstract

Staphylococcus aureus is a ubiquitous pathogen which causes infections both in healthy individuals as well as in hospitalized patients. This study aimed to investigate the prevalence of antibiotic resistance and exfoliative toxin A (eta) gene in S. aureus strains isolated from patients and healthy individuals in northern Iran. In this cross-sectional study from November 2014 to 2015, a total of 63 S. aureus isolates from patients and 63 isolates of 262 nasal swabs from healthy individuals were collected. S. aureus isolates were identified by standard microbiologic tests. Antimicrobial susceptibility testing was carried out by disk diffusion method. The presence of eta gene was determined by PCR method. Among both the patients and healthy individuals, the highest antibiotic resistance was noted toward penicillin G. In clinical isolates of S. aureus, 22 (34.9%) MRSA and 41 (65.1%) MSSA were detected. Among healthy individuals isolates, 2 (3.2%) MRSA and 61 (96.8%) MSSA were found. The prevalence of eta gene in isolates from patients and healthy individuals were 22 (34.9%) and 18 (28.6%), respectively. In summary, as the first study report of the prevalence of exfoliative toxin A in our region, we found a lower rate compared to other parts of the country. Also, the presence of eta gene in all types of clinical samples must be considered as a serious health problem and demand effective infection control policy.