Detection of clonal relationship of methicillin resistant staphylococcus aureus strains with spa typing and pulsed field gel electrophoresis methods

Aim: Methicillin-Resistant Staphylococcus aureus infection, first emerged in England, has spread rapidly throughout the world including other European countries primarily. Rapid detection of agent sources and transmission routes by molecular methods, provide a key data about the infection control for active risk management of Methicillin Resistant Staphylococcus aureus-induced infections in both community and also hospitals. This study aims to refer the dominant clones of our region and compare methods by determining clonal releationship of Methicillin Resistant Staphylococcus aureus strains, that have been isolated from our hospital, using Pulsed Field Gel Electrophoresis and spa typing methods. Material and Methods: Seventy five Methicillin Resistant Staphylococcus aureus isolates identified by Vitek 2 system, which has been routinely usen in our hospital, were typed by Pulsed Field Gel Electrophoresis using SmaI enzyme. Sequence analysis was performed after amplification of spa gene regions. Obtained data was evaluated by StaphType (Ridom) software and spa types were identified. Results: It is found that 75 samples analyzed by Pulsed Field Gel Electrophoresis, were gathered in 11 clusters and also A (n = 19) and B (n = 27) clusters which were similar to each other in the ratio of 84,1% were constituted the 61,3% of all strains. It is detected that all isolates were also distributed in 18 spa types when evaluated by spa typing. It is observed that the largest spa cluster was t030 with 31 isolates (41.3%) and it was followed by t223 type with 9 isolates (12%). Conclusions: By evaluation of the genotypic investigations of the isolates, antibiotic resistance profiles and isolation rate from cases defined as hospital infection, it is was considered that t030 was dominant genotype with the incidence rate of 41,3 % and this gene cluster generated the hospital clones. t223 and t127 were considered to be community-associated spa types and they were determined in ratio of 12 % and 9,3% respectively. It is thought to be beneficial using spa typing methods with Pulsed Field Gel Electrophoresis in short-term epidemic studies, in the research of long-term clonal relations and also using this study with more examples and for longer time to monitor community and hospital associated clones.