Nosocomial infections caused by methicillin-resistant staphylococci (MRSA) pose a serious problem in
many countries. This study aimed to determine the antibacterial susceptibility patterns of methicillin
sensitive and resistant Staphylococcus aureus isolates from the hospitalized patients. Totally 356 isolates
of Staphylococcus aureus (S. aureus) including 200, 137 and 19 corresponding to MSSA, MRSA, and
intermediate MRSA strains, respectively were isolated. Antibacterial susceptibility patterns of the isolates
to 14 antibiotics were examined using Kirby-Bauer method. MICs of 15 antibiotics to 156 MRSA isolates
were determined by E test method. Cross-resistances of MRSA isolates (137+19) to the other tested
antibiotics were also determined. S.aureus with high frequencies were isolated from the blood, sputum and
deep wound samples. All of 200 MSSA isolates were sensitive to oxacillin, vancomycin, tecoplanin,
rifampin, linezolid, quinupristin/dalfopristin, mupirocin and fusidic acid. A gradient of reduced
susceptibility of MSSA to cephalexin, co-trimoxazole, ciprofloxacin, clindamycin, tetracycline,
erythromycin and gentamicin were evident. MRSA isolates were sensitive to vancomycin, tecoplanin,
linezolid, quinupristin/dalfopristin, mupirocin and fusidic acid, while reduced susceptibility of them to
rifampin, co-trimoxazole, clindamycin, cephalexin, tetracycline, ciprofloxacin, erythromycin and
gentamicin were observed. MRSA isolates exhibited a high range of cross-resistance to the eight tested
antibiotics. Overall, co-trimoxazole, ciprofloxacin, clindamycin, tetracycline, erythromycin and gentamicin
showed low activity against MSSA and MRSA isolates which may indicate they are not suitable to be used
in clinical practices. To preserve the effectiveness of antibiotics, rational prescription and concomitant
application of preventive measures against the spread of MRSA are recommended.
