Rapid Detection of Methicillin-Resistant Staphylococcus aureus Isolates by Turanose Fermentation Method.
BACKGROUND
Methicillin-Resistant Staphylococcus aureus (MRSA) is a major pathogen in the hospital and community settings. Rapid methods to diagnose S. aureus infections are sought by many researchers worldwide. The current study aimed to utilize a phenotypic method of turanose fermentation to identify methicillin-susceptible and resistant S. aureus.


OBJECTIVE
The current study aimed to assay the turanose metabolism at different dilutions as a rapid phenotypic method to identify MRSA isolates.


METHODS
A total of 150 Staphylococcus isolates were collected from Tehran health centers. Staphylococcus aureus isolates were identified based on cultural characteristics, biochemical reactions and positive tube coagulase test. Methicillin resistance was determined by the disk diffusion method. The Polymerase Chain Reaction amplification was used to detect the mecA gene in MRSA isolates. All the methicillin-resistant and susceptible isolates were evaluated for turanose metabolism with 1%, 0.7% and 0.5% dilutions using the microplate method.


RESULTS
Out of the 150 staphylococcal isolates, 80 were identified as S. aureus. Among which 40 (50%) of the isolates were MRSA. The mecA gene was present in all S. aureus isolates resistant to methicillin. A considerable difference was also observed between susceptible and resistant isolates of S. aureus at a 0.7% dilution of turanose.


CONCLUSIONS
Since it is highly important to rapidly detect MRSA isolates, especially in nosocomial infections, phenotypic methods may certainly be useful for this purpose. Resistance to methicillin in S. aureus shows a substantially increased ability in turanose metabolism. It is concluded that fermentation of turanose at 0.7% dilution could be a rapid detection method for primary screening of MRSA isolates.
Department of Microbiology, Pasteur Institute of Iran, Tehran, IR Iran.
Javad
J
Raeisi
Department of Mycobacteriology, Pasteur Institute of Iran, Tehran, IR Iran.
Mahnaz
M
Saifi
Department of Microbiology, Pasteur Institute of Iran, Tehran, IR Iran.
Mohammad Reza
MR
Pourshafie
Department of Molecular Biology, Pasteur Institute of Iran, Tehran, IR Iran.
Mohammad Reza
MR
Asadi Karam
Department of Microbiology, Islamic Azad University, Arak Branch, Arak, IR Iran.
Hamid Reza
HR
Mohajerani
MRSA; Staphylococcus aureus; Turanose