M serotyping of group A beta haemolytic streptococci isolated from throat infection by emm-gene sequence analysis from Turkey
Abstract number: P644
Akca G., Sultan N., Engin D., Yalinay Cirak M., Olguntürk R.
Objective: Following group A beta haemolytic streptoccoci related throat infections, invasive diseases may occur due to several virulence factors such as M protein. The purpose of this study is to determine emm types of Turkish people suffering throat infections and investigate the relation between M-types, sex, age and type of diseases.
Methods: 114 S. pyogenes strains were isolated from throat cultures and identified with conventional microbiological methods (culture, serotyping, API Strep®). emm specific PCR products of these strains were obtained using emmP1, emmP2 primers recommended by Centers of Disease Control. emm types of the strains were sequenced by DNA cycle-sequencing analyse. Local and global alignments were performed by Clustal W v1.7 software and Blast server. Phylogenetic dendrogram was drawn. The correlation between "emm" types and sex of the patients have been evaluated by Chi-square test statistically. The distribution of age and "emm" types of the patients were analysed by Mann-Whitney U test.
Results: Of the 114 strains (85%), 97 strains' emm types were identified as 1, 3, 4, 6, 9, 11, 12, 14, 18, 22, 24, 29, 33, 43, 48, 75, 77, 78, 89, 90, 102, 112, 118. The other 17 types could not have been identified and accepted as nontypeable. The most frequently seen types were emm 12, 3, 1, 75, 29 respectively which were isolated from school age children under 10-years-old. The patients' age distribution was found variable but mostly accordant to emm types which were identified from invasive streptococcal infections. It was found that there's no statistically significant difference between the emm types and the sex of the patients. Besides, 15 of emm/M types which were determined in this study, including the most frequently seen types (emm 1, 3 and 12) were found that they were also in the contents of M types of 26 VV vaccine (suggested to be effective as 76.9%) developed for Group A streptococci (GAS)
Conclusion: This preliminary study is the first emm-gene sequence analysis presented from Turkey which determines the M types of GAS strains in our country. If the research can be generalised to all different regions we will get more exactly and comprehensive results about the M types of Turkish people.
|Session name:||18th European Congress of Clinical Microbiology and Infectious Diseases|
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