| Congresso Brasileiro de Microbiologia 2023 | Resumo: 1180-1 | ||||
Resumo:Streptococcus pyogenes (S. pyogenes) is a human pathogen that affects people of all ages, but the infant population is the most affected worldwide, its severity is related to the production of virulence factors and its genetic variability. Paraguay has no published data on the molecular characterization of S. pyogenes. This work was carried out to determine the genetic variability and virulence factors of S. pyogenes isolated from children and adolescents in a Paraguayan hospital from 2016 to 2020. This observational, descriptive, cross-sectional study included 85 S. pyogenes isolates from invasive (blood culture) and non-invasive (pharyngeal swab and purulent discharge) infections in children and adolescents aged 0 to 17 years attending the General Pediatric Hospital ¨Niños de Acosta Ñu¨ of Paraguay. The coding genes for speA, speB, speC, speG, speK, speL, ssa and smeZ toxins were detected by PCR. Amplification of the emm gene was performed by PCR, sequencing by the Sanger method and typing was performed using the online software available at the official CDC website. Statistical analysis was performed according to Fisher's exact test (p<0.05 statistically significant). Most isolates carried at least four virulence factors. The genes most frequently present in non-invasive infections were speG, smeZ, speB and speC, present in 93%, 83%, 81% and 53% of the samples, respectively. The speK gene was found exclusively in 11% of non-invasive samples. And genes most frequently in invasive infections were speG, speB, smeZ and speC, detected in 100%, 90%, 80% and 70% of them, respectively. Twenty-eight emm types were detected, those most frequent were emm1.0, emm8.2, emm1.3, and emm87. The presence of emm1.3 in invasive isolates presents statistically significant difference. This is the first report on the molecular classification and virulence profile of S. pyogenes performed in Paraguay. There is great variability in the virulence profiles observed, even among isolates with the same emm genotype. The most frequently found emm genotypes are related to more severe infections worldwide. Palavras-chave: GENETIC VARIABILITY, Paraguayan children and adolescents, Streptococcus pyogenes, VIRULENCE PROFILE | |||||