Antibacterial resistance pattern and frequency of methicillin-resistant staphylococcus aureus isolated from different sources in southeastern Iran

ABSTRACT

The frequency of methicillin-resistant Staphylococcus aureus [MRSA] was determined in 526 bacteria isolates from the infected sites of patients with staphylococcal infection, and from the nose or throat of healthy carriers among hospitalized patients, hospital personnel and the control group not in contact with hospitalized patients. Total number of the resistant isolates [or with immediate response] to 1micro g oxacillin was 9.9% and considered as MRSA. Vancomycin and trimethoprim-sulfamethoxazole were the most active antibacterial agents against all the bacterial isolates [p<0.001], followed by erythromycin [93.5%], and gentamicin [93.3%]. Sensitivity to penicillin, ampicillin and amoxicillin was very low [less than 4%]. The rate of MRSA and antibacterial resistance was higher in the S. aureus isolated from clinical infection [25%], compared with those from carriers [7.9%] p<0.001. Among the bacteria isolated from carriers, throat samples showed a higher rate of resistance to antimicrobial agents and a higher rate of MRSA [13.3%] compared to those isolated from the nose [5.2%], p<0.002