Antimicrobial Resistance Pattern and agr Typing among Staphylococcus aureus Isolated from Nasal Carrier Personnel in Shahid Beheshti Hospital in Yasuj City

Based on the important role of nasal carriers of Staphylococcus aureus in hospital settings and their importance in the transmission of bacterium to patients and other personnel, the aim of the present study was to determine the frequency of nasal carriers, antibiotic resistance patterns and genotyping of S. aureus isolated from personnel of Shahid Beheshti hospital in Yasuj city (Iran) using the agr typing method.
In this cross-sectional study, a total of 347 nasal samples were collected from the healthcare workers of Shahid Beheshti Hospital in order to identify S. aureus. Cefoxitin containing disks and detection of the mecA gene were used for the identification of methicillin resistant isolates. The antimicrobial susceptibility patterns of isolates were tested against 15 different antibiotics using the Disc Agar Diffusion method. The Multiplex-PCR method was used for the agr typing of S. aureus isolates.
Ninety-three (26.8%) of personnel were nasal carriers of S. aureus, among them 9 isolates were identified as MRSA. Among agr groups, agrI (40.9%) and agrIII (40.9%) were the prominent genotypes. All of the isolates (100%) were resistant to Penicillin. The resistance rate to erythromycin and co-trimoxazole were 12.9% and 5.38% respectively. Most of the isolates were sensitive to other antibiotics.
Based on the low resistance rate of S. aureus, it appears that the eradication of nasal carrier states could be possible. S. aureus agr types I and III have an important role in nasal colonization in comparison to other agr types.