Distribution of emm and superantigen genotypes in responsible strains for invasive group A streptococcus infections, clinical correlation and determination of phylogenetic relationships

Group A Streptococcus (GAS), are the major bacterial agents of tonsillopharyngitis observed between the 5-15 age group. GAS causes late complications such as respiratory system infections, primary suppurative infections of skin and soft tissue, rheumatic fever, glomerulonephritis , and also associated with the diseases in a few cases of necrotizing fasiit, bacteremia, toxic streptococcus shock syndrome (STSS), puerperal sepsis, pneumonia and menengitis with high mortality. M protein is responsible for adhesion and invasion to escape from host immune response and the formation of the immunopathogenesis as well as the numerous adhesive and invasive proteins in virulence of GAS. Until today over than 250 M genotypes were determined. The relationship between M protein genotypes and prognosis of infection was shown and the predictive importances of M genotype for prognosis were reported. It is considered that serotyping of M protein or determination of emm genotype is gold standard for surveillance of GAS infections. On the other hand, the role of superantigens (Sags) secreted by GAS in the pathogenesis of malignant characterized streptococcus infections has been proven. In this study, distribution of emm genotypes, Sags genes, the relation between clinical table and these genotypes and the phylogenetic properties of this relation among the GAS strains isolated from the clinical samples taken from the patients with clinical symptoms excluding tonsillopharyngitis were investigated. Test strains were obtained from Central Laboratory of Çukurova University Balcalı Hospital and regional hospitals. M protein of Group A streptococcus was typed by sequence analysis of emm genes. Sags and other virulence gene profiles of GAS isolates were determined by polymerase chain reaction (PCR) method. Clonal relationships between strains were described by the Pulsed-field gel electrophoresis (PFGE) method. As a result of emm-PCR was found positive emm genes in 86 isolates. emm typing using the CDC database have been identified 22 (%25.58) different emm types. When examined the prevalence of emm type, it was found that the most common type is emm28 (%22.09), emm1 (%18.60), emm12 (%13.95), emm3 (%11.62) and emm89 (%3.48), respectively. When the detection and prevalence of virulence genes such as SAgs types, Dnase, protease were examined, the most prevalent types were SpeG (%58.13), SpeC (%56.97), sdaB (%53.48), mac (%53.48) genes. PFGE analysis showed no significant clonal relationship between isolates. In conclusion, regional studies are needed for the detection and prevalence of GAS virulence factors in our country.