Accessory gene regulator specificity groups among Staphylococcus aureus isolated from hospitalized children

Abstract

Background: Staphylococcus aureus (S. aureus) especially those with methicillin resistance are human pathogens capable of causing a wide variety of diseases, ranging from mild skin lesions to systemic and fatal infections. Objectives: The aim of this study was to detect the accessory gene regulator (agr) specificity groups among methicillin resistant and susceptible S. aureus isolated from children. Materials and Methods: During July 2012 to January 2013, 22 S. aureusc linical isolates were collected from children aged between 2 to 11, in Loghman Hospital of Tehran. Antibiogram test was performed using disc diffusion method. Polymerase chain reaction (PCR) was conducted to detect mecA gene and agr specificity groups. Results: Among 22 S. aureus clinical isolates collected from children, five isolates (22.7 %) were resistant to methicillin. fourteen isolates (63.6%) were resistant to amoxicillin and all were susceptible to vancomycin and linezolid. Agr specificity group I was detected in 12 (54.5%) isolates (in 2 MRSA and 10 MSSA isolates), agr group II in four (18%, in 3 MSSA and 1 MRSA), group III in 3 (9%, 2 in MSSA and one in MRSA), while agr specificity group IV was found in three (13.6%, 2 MSSA and 1 MRSA) isolates. Conclusions: The agr specific group I had the highest rate of detection among pathogens isolated from hospitalized children in Tehran.