Isolation and identification of the streptococcus pyogenes causing acute tonsillitis and detecting for some virulence factor by PCR

In this study, 100 samples were collected from tonsillitis patients of both genders aged 1- 40 years who applied to Al-Harith National Hospital in Salah al-Din Governorate of Iraq between 9/10/2021-30/01/2022. The isolates were diagnosed by bastracin susceptibility as well as microscopic and culture characteristics and biochemical tests, and the diagnosis was confirmed by the Vitek 2 system. The isolation rate was recorded as 10%, ie 10 isolates belonged to Streptococcus pyogenes. The results showed that the highest isolation rate was 76% in tonsil samples and the highest isolation rate was in the 1-10 age group. Some of the virulence factors of these bacteria were also examined and the results showed that all isolates have bacterial encapsulation and the ability to produce DNase and hemolysin enzymes in addition to their biofilm forming abilities. Drug susceptibility testing was performed for all isolates of 10 antibiotics. All isolated bacteria were highly sensitive to Amoxicillin clavulanic, Imipenem, Meropenem and Levofloxacin and highly resistant to Amoxicillin and Ampicillin. Some virulence factors were studied molecularly and using thermal polymerase PCR technique. Agarose gel electrophoresis results revealed that all isolates contained Emm, ScpA, Spe1 and GyrB genes