| Congresso Brasileiro de Microbiologia 2023 | Resumo: 1264-1 | ||||
Resumo:Neisseria gonorrhoeae has become a threat to global public health due to the accumulation of resistance mechanisms, putting at risk the combined therapy of azithromycin and ceftriaxone, currently adopted in many countries. In this scenario, the ST-1901 sequence type (ST) draws attention for its high incidence in surveillance programs and for the occurrence of chromosomal resistance mechanisms, including the emergence of ceftriaxone resistance related to the penA mosaic gene. This study aimed to describe the evolution of the ST-1901 and its single locus variants in Rio de Janeiro from 2006 to 2022. Based on antimicrobial susceptibility testing and whole genome sequencing, a total of 82 N. gonorrhoeae isolates were analyzed according to antimicrobial susceptibility profile, resistance mechanisms, plasmid typing, molecular typing (MLST, NG-MAST and NG-STAR), and phylogenetics (core genome SNPs). Seven different sequence types were detected: ST-1901 (60) and its single-locus variants ST-1579 (1), ST-1902 (1), ST-7822 (10), ST-9365 (1), ST-11107 (3) and ST-11602 (5). The susceptibility profile revealed a high incidence of isolates not susceptible to penicillin, ciprofloxacin and tetracycline (99%, 94% and 55%, respectively). Against azithromycin, 36% of the isolates are not susceptible. In contrast, all isolates were susceptible to ceftriaxone. The phylogenetic analysis grouped the isolates by five clades, whose distribution was associated with the resistance mechanisms, three related to ST-1901 and two to ST-7822. The typification of the mechanisms of resistance to azithromycin identified the occurrence of 5 different types of mutations in mtrR, especially DelA in 89% of the collection, and G45D, A39T and Nm-Like mutations concentrated in ST-7822. ST-7822 strains also carry conjugative plasmids, differently from the other STs. C2611T mutations in rrl were detected in 15% of the isolates, mainly after 2013, and in different clades and STs. For ceftriaxone, six penA types were identified, especially types 2, 5 and 34 mosaic. The isolates with penA type 34 mosaic, which belong to the internationally relevant MLST-1901 and ST-90 of NG-MAST, were detected in isolates since 2009. Our study indicates that ST-1901 and its single locus variant ST-7822 need to be monitored in Rio de Janeiro because they have genetic bases favorable for the evolution to resistance to the antimicrobial agents adopted in the combined therapy against gonorrhea, azithromycin and ceftriaxone. Palavras-chave: antimicrobial resistance, molecular typing, Neisseria gonorrhoeae, phylogeny, whole genome sequencing Agência de fomento:Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ); INPRA – Instituto Nacional de Pesquisa em Resistência Antimicrobiana – Brazil (INCT/CNPq: 465718/2014-0). Sequencing of the isolates was supported by the CDC NCHH | |||||