RESUMO
Multidrug-resistant (MDR) and extended-spectrum ß-lactamase (ESBL)-producing Klebsiella pneumoniae associated with nosocomial infections have caused serious problems in antibiotic management with limited therapeutic choices. This study aimed to determine the genotypic and phenotypic characteristics of K. pneumoniae strains isolated from a tertiary hospital in Malaysia. Ninety-seven clinical K. pneumoniae strains were analyzed for antimicrobial susceptibility, all of which were sensitive to amikacin and colistin (except one strain), while 31.9 % and 27.8 % were MDR and ESBL producers, respectively. PCR and DNA sequencing of the amplicons indicated that the majority of MDR strains (26/27) were positive for blaTEM, followed by blaSHV (24/27), blaCTX-M-1 group (23/27), blaCTX-M-9 group (2/27), and mcr-1 (1/27). Thirty-seven strains were hypervirulent and PCR detection of virulence genes showed 38.1 %, 22.7 %, and 16.5 % of the strains were positive for K1, wabG, and uge genes, respectively. Genotyping by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) showed that these strains were genetically diverse and heterogeneous. Sequence types, ST23, ST22, and ST412 were the predominant genotypes. This is the first report of colistin-resistant K. pneumoniae among clinical strains associated with mcr-1 plasmid in Malaysia. The findings in this study have contributed to the effort in combating the increase in antimicrobial resistance by providing better understanding of genotypic characteristics and resistance mechanisms of the organisms.
Assuntos
Colistina/farmacologia , Klebsiella pneumoniae/isolamento & purificação , Virulência/genética , beta-Lactamases/genética , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana/genética , Farmacorresistência Bacteriana Múltipla/genética , Eletroforese em Gel de Campo Pulsado , Genes Bacterianos , Técnicas de Genotipagem , Humanos , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/genética , Malásia/epidemiologia , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Centros de Atenção TerciáriaRESUMO
INTRODUCTION:: This study aimed to develop a duplex endpoint PCR assay for rapid detection and differentiation of Leptospira strains. METHODS:: Primers were designed to target the rrs (LG1/LG2) and ligB (LP1/LP2) genes to confirm the presence of the Leptospira genus and the pathogenic species, respectively. RESULTS:: The assay showed 100% specificity against 17 Leptospira strains with a limit of detection of 23.1pg/µl of leptospiral DNA and sensitivity of 103 leptospires/ml in both spiked urine and water. CONCLUSIONS:: Our duplex endpoint PCR assay is suitable for rapid early detection of Leptospira with high sensitivity and specificity.
Assuntos
Primers do DNA , DNA Bacteriano , Leptospira/classificação , Reação em Cadeia da Polimerase/métodos , DNA Bacteriano/isolamento & purificação , Leptospira/genética , Leptospira/isolamento & purificação , Sensibilidade e Especificidade , Especificidade da EspécieRESUMO
Abstract INTRODUCTION: This study aimed to develop a duplex endpoint PCR assay for rapid detection and differentiation of Leptospira strains. METHODS: Primers were designed to target the rrs (LG1/LG2) and ligB (LP1/LP2) genes to confirm the presence of the Leptospira genus and the pathogenic species, respectively. RESULTS: The assay showed 100% specificity against 17 Leptospira strains with a limit of detection of 23.1pg/µl of leptospiral DNA and sensitivity of 103 leptospires/ml in both spiked urine and water. CONCLUSIONS: Our duplex endpoint PCR assay is suitable for rapid early detection of Leptospira with high sensitivity and specificity.