RESUMO
Despite the rapid spread of antibiotic resistance among gonococci worldwide, limited reports are available from Brazilian locations. In the present study, 25 quinolone-resistant Neisseria gonorrhoeae (QRNG) strains isolated in Rio de Janeiro, Brazil, were characterized by phenotypic and molecular methods, including analysis of mutations in the gyrA and parC genes. They represented 16.5% of the N. gonorrhoeae isolates obtained during a survey performed from 2006 to 2010. A trend for increasing resistance to ciprofloxacin was observed in the period investigated. The most prevalent pattern of mutation observed among QRNG isolates, Ser-91 to Phe and Asp-95 to Gly in gyrA and Ser-87 to Arg in parC, was detected in 40% of the isolates exhibiting MICs ranging from 4 to >32 µg/ml. Rare types of mutations were found in the gyrA gene (Gln-102 to His [12%] and Asp-95 to Tyr [4%]) and in the parC gene (Ser-88 to Thr [4%]). The genetic relationship of the QRNG isolates, evaluated by pulsed-field gel electrophoresis, suggested that the increase in the frequencies of the QRNG isolates in Rio de Janeiro, Brazil, may have arisen as a result of simultaneous spread of two clonal groups. The results also indicate that fluoroquinolones may no longer be used as first line antibiotics for the treatment of gonorrhea in Rio de Janeiro, and that programs for antimicrobial susceptibility surveillance of N. gonorrhoeae should also be implemented in other regions of Brazil.
Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Gonorreia/epidemiologia , Gonorreia/microbiologia , Neisseria gonorrhoeae/efeitos dos fármacos , Quinolonas/farmacologia , Substituição de Aminoácidos , Brasil/epidemiologia , Análise por Conglomerados , DNA Girase/genética , DNA Topoisomerase IV/genética , DNA Bacteriano/genética , Eletroforese em Gel de Campo Pulsado , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Tipagem Molecular , Mutação de Sentido Incorreto , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/isolamento & purificação , Neisseria gonorrhoeae/fisiologiaRESUMO
Group B streptococci (GBS) infections occur worldwide. Although serotyping has been used for epidemiologic purposes, this does not accurately characterize enough members of a genetically heterogeneous bacterial population. The aims of this work were to evaluate the genetic diversity of 45 type Ia GBS strains isolated in Brazil by pulsed-field gel electrophoresis as well as to evaluate antimicrobial susceptibility profiles and identify virulence genes. Twenty-four strains were assigned to cluster A. All strains under study contained the hylB and scpB genes. The bca gene was detected in only 10 strains and none of the streptococci carried the bac gene. Thirty-nine strains were resistant to tetracycline.
Assuntos
Antibacterianos/farmacologia , DNA Viral/análise , Genes Virais/genética , Streptococcus agalactiae , Brasil , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Eletroforese em Gel de Campo Pulsado , Variação Genética , Humanos , Streptococcus agalactiae/efeitos dos fármacos , Streptococcus agalactiae/genética , Streptococcus agalactiae/patogenicidade , Virulência/genéticaRESUMO
Group B streptococci (GBS) infections occur worldwide. Although serotyping has been used for epidemiologic purposes, this does not accurately characterize enough members of a genetically heterogeneous bacterial population. The aims of this work were to evaluate the genetic diversity of 45 type Ia GBS strains isolated in Brazil by pulsed-field gel electrophoresis as well as to evaluate antimicrobial susceptibility profiles and identify virulence genes. Twenty-four strains were assigned to cluster A. All strains under study contained the hylB and scpB genes. The bca gene was detected in only 10 strains and none of the streptococci carried the bac gene. Thirty-nine strains were resistant to tetracycline.
