RESUMEN
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.
Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Gonorrea/epidemiología , Gonorrea/microbiología , Neisseria gonorrhoeae/efectos de los fármacos , Quinolonas/farmacología , Sustitución de Aminoácidos , Brasil/epidemiología , Análisis por Conglomerados , Girasa de ADN/genética , Topoisomerasa de ADN IV/genética , ADN Bacteriano/genética , Electroforesis en Gel de Campo Pulsado , Genotipo , Humanos , Pruebas de Sensibilidad Microbiana , Epidemiología Molecular , Tipificación Molecular , Mutación Missense , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/aislamiento & purificación , Neisseria gonorrhoeae/fisiologíaRESUMEN
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.
Asunto(s)
Antibacterianos/farmacología , ADN Viral/análisis , Genes Virales/genética , Streptococcus agalactiae , Brasil , Pruebas Antimicrobianas de Difusión por Disco , Electroforesis en Gel de Campo Pulsado , Variación Genética , Humanos , Streptococcus agalactiae/efectos de los fármacos , Streptococcus agalactiae/genética , Streptococcus agalactiae/patogenicidad , Virulencia/genéticaRESUMEN
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.