Comparison of the Results of Polymerase Chain Reaction and Oxacillin Agar Dilution Methods in Determining Resistance to Methicillin in Isolated Staphylococcus Aureus at Alzahra Hospital, Isfahan, Iran

Background: Staphylococcus aureus is an important infectious bacterium. The pathogenicity of this bacterium is critical in both society and hospital. It is a human normal flora that exists in the upper respiratory tract of 25% of healthy individuals. It causes a wide spectrum of diseases ranging fro...

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Main Authors: Sayed Asghar Havaei, Mohsen Karbalaeizadeh babaki, Ebtehaj Pishva
Format: Article
Language:fas
Published: Isfahan University of Medical Sciences 2012-03-01
Series:مجله دانشکده پزشکی اصفهان
Subjects:
Online Access:http://jims.mui.ac.ir/index.php/jims/article/view/1402
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author Sayed Asghar Havaei
Mohsen Karbalaeizadeh babaki
Ebtehaj Pishva
author_facet Sayed Asghar Havaei
Mohsen Karbalaeizadeh babaki
Ebtehaj Pishva
author_sort Sayed Asghar Havaei
collection DOAJ
description Background: Staphylococcus aureus is an important infectious bacterium. The pathogenicity of this bacterium is critical in both society and hospital. It is a human normal flora that exists in the upper respiratory tract of 25% of healthy individuals. It causes a wide spectrum of diseases ranging from skin infections to severe infections including septicemia, endocarditis, pneumonia, and skin abscess. S. aureus is a considerable factor of severe infections in both society and hospital. Methicillin resistant S. aureus (MRSA) strains have high mortality rates. Therefore, the rate of MRSA must be quickly identified and controlled with treating measures. Methods: A total number of 114 strains of S. aureus were obtained from the specimens at Alzahra Hospital, Isfahan, Iran. Minimum inhibitory concentration (MIC) of oxacillin for MRSA was performed with agar dilution method and eventually polymerase chain reaction (PCR) for mecA gene. Findings: Out of 114 samples, 35 isolates had mecA gene that were assessed with agar dilution method. According to the Clinical and Laboratory Standards Institute (CLSI), MIC of oxacillin in agar dilution method was 8 µg/ml and results was recorded. MecA gene PCR was conducted for all strains and the results were compared with agar dilution method. From resistant isolates, 4% of the strains had mecA gene but were susceptible to methicillin in phenotypic method. Conclusion: Our study showed agar dilution method to be more sensitive and specific than disk diffusion method. PCR is the best method to indentify susceptible and resistant strains to methicillin. Some strains were susceptible to oxacillin in phenotypic method but their mecA gene was identified with PCR.
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spelling doaj.art-c0f021020fe4487ba548c67a070c65b82023-09-02T14:27:23ZfasIsfahan University of Medical Sciencesمجله دانشکده پزشکی اصفهان1027-75951735-854X2012-03-012915111751182963Comparison of the Results of Polymerase Chain Reaction and Oxacillin Agar Dilution Methods in Determining Resistance to Methicillin in Isolated Staphylococcus Aureus at Alzahra Hospital, Isfahan, IranSayed Asghar Havaei0Mohsen Karbalaeizadeh babaki1Ebtehaj Pishva2Associate Professor, Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, IranMSc Student, Student Research Committee, Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, IranAssociate Professor, Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, IranBackground: Staphylococcus aureus is an important infectious bacterium. The pathogenicity of this bacterium is critical in both society and hospital. It is a human normal flora that exists in the upper respiratory tract of 25% of healthy individuals. It causes a wide spectrum of diseases ranging from skin infections to severe infections including septicemia, endocarditis, pneumonia, and skin abscess. S. aureus is a considerable factor of severe infections in both society and hospital. Methicillin resistant S. aureus (MRSA) strains have high mortality rates. Therefore, the rate of MRSA must be quickly identified and controlled with treating measures. Methods: A total number of 114 strains of S. aureus were obtained from the specimens at Alzahra Hospital, Isfahan, Iran. Minimum inhibitory concentration (MIC) of oxacillin for MRSA was performed with agar dilution method and eventually polymerase chain reaction (PCR) for mecA gene. Findings: Out of 114 samples, 35 isolates had mecA gene that were assessed with agar dilution method. According to the Clinical and Laboratory Standards Institute (CLSI), MIC of oxacillin in agar dilution method was 8 µg/ml and results was recorded. MecA gene PCR was conducted for all strains and the results were compared with agar dilution method. From resistant isolates, 4% of the strains had mecA gene but were susceptible to methicillin in phenotypic method. Conclusion: Our study showed agar dilution method to be more sensitive and specific than disk diffusion method. PCR is the best method to indentify susceptible and resistant strains to methicillin. Some strains were susceptible to oxacillin in phenotypic method but their mecA gene was identified with PCR.http://jims.mui.ac.ir/index.php/jims/article/view/1402Staphylococcus aureusMecA geneMethicillin resistant strains
spellingShingle Sayed Asghar Havaei
Mohsen Karbalaeizadeh babaki
Ebtehaj Pishva
Comparison of the Results of Polymerase Chain Reaction and Oxacillin Agar Dilution Methods in Determining Resistance to Methicillin in Isolated Staphylococcus Aureus at Alzahra Hospital, Isfahan, Iran
مجله دانشکده پزشکی اصفهان
Staphylococcus aureus
MecA gene
Methicillin resistant strains
title Comparison of the Results of Polymerase Chain Reaction and Oxacillin Agar Dilution Methods in Determining Resistance to Methicillin in Isolated Staphylococcus Aureus at Alzahra Hospital, Isfahan, Iran
title_full Comparison of the Results of Polymerase Chain Reaction and Oxacillin Agar Dilution Methods in Determining Resistance to Methicillin in Isolated Staphylococcus Aureus at Alzahra Hospital, Isfahan, Iran
title_fullStr Comparison of the Results of Polymerase Chain Reaction and Oxacillin Agar Dilution Methods in Determining Resistance to Methicillin in Isolated Staphylococcus Aureus at Alzahra Hospital, Isfahan, Iran
title_full_unstemmed Comparison of the Results of Polymerase Chain Reaction and Oxacillin Agar Dilution Methods in Determining Resistance to Methicillin in Isolated Staphylococcus Aureus at Alzahra Hospital, Isfahan, Iran
title_short Comparison of the Results of Polymerase Chain Reaction and Oxacillin Agar Dilution Methods in Determining Resistance to Methicillin in Isolated Staphylococcus Aureus at Alzahra Hospital, Isfahan, Iran
title_sort comparison of the results of polymerase chain reaction and oxacillin agar dilution methods in determining resistance to methicillin in isolated staphylococcus aureus at alzahra hospital isfahan iran
topic Staphylococcus aureus
MecA gene
Methicillin resistant strains
url http://jims.mui.ac.ir/index.php/jims/article/view/1402
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