A Comparison study to determine glycopeptide resistance in Staphylococcus aureus isolates collected from Shohada Hospital during three years

Subject Areas : Medical Microbiology

shahrzad Ghasemi Saberi ¹ , Haiedeh Mobaiyen ² , Jeinus Bayat Makoo ³ , Sanam Sadeghi Mohammadi ⁴

1 - G.P., Department of Microbiology, Faculty of Medicine, Tabriz branch, Islamic Azad University, Tabriz, Iran.
2 - Assistant Professor, Department of Microbiology, Faculty of Medicine, Tabriz branch, Islamic Azad University, Tabriz, Iran.
3 - Associate Professor, Department of Infectious Diseases, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
4 - M.Sc., Department of Microbiology, Faculty of Medicine, Tabriz branch, Islamic Azad University, Tabriz, Iran.

Received: 2014-03-06 Accepted : 2014-06-08 Published : 2015-09-01

Keywords: Glycopeptide, Vancomycin-resistant Staphylococcus aureus, Vancomycin screening plate method, Disk agar diffusion method,

Abstract :

Background & Objectives: Glycopeptides such as vancomycin and ticoplanin are commonly used as antibiotic of choice for treatment of infections caused by methicillin-resistant Staphylococcus aureus. Following first reports of vancomycin resistant strains, the presence and distribution of these bacteria have been continuously investigated in the clinic centers. This study was aimed to investigate the distribution of glycopeptide resistant S. aureus isolated from Shohada hospital during a period of three years. Materials & Methods: This cross-sectional study was carried out on 182 S. aureus strains isolated from wound orthopedic patients in three years. Resistance against glycopeptides, linezolid and ciprofloxacin were examined by disk agar diffusion method. Screening plate method containing 6µg / ml of vancomycin was used for resistance against vancomycin. Results: Among the 182 isolates, only 2 cases (1.09%) were confirmed as vancomycin-resistant S. aureus, VISA strains. In isolates from the last year of sampling, the resistance was controlled.  Among total isolates, in 31 isolates (17%) demonstrated intermediate reaction against ticoplanin. Conclusion: Significant differences are indicated between glycopeptide resistances isolated from different years, despite a report of two VISA isolates in our center, which showed that the resistance controlled by the authorities.