RESUMO
The role of mechanical ventilation and catheters in favouring Acinetobacter baumannii infections needs to be better understood. This study evaluated the adherence of 19 isolates of different hospital clusters of A. baumannii to abiotic surfaces and epithelial cells (HEp-2). Of the hydrophobic isolates, 80% adhered to polystyrene, indicating a close relationship between hydrophobicity and adherence. All isolates adhered to epithelial cells to different degrees, and 73·7% showed an aggregated pattern. Analysis of the serum resistance of catheter-tip isolates showed that all were resistant. These worrisome results showed that the high capacity of A. baumannii to adhere to surfaces and survive in human serum could hinder treatment and control of this pathogen.
Assuntos
Acinetobacter baumannii/fisiologia , Aderência Bacteriana , Células Epiteliais/microbiologia , Infecções por Acinetobacter/microbiologia , Antibacterianos/farmacologia , Linhagem Celular , Farmacorresistência Bacteriana Múltipla , Hospitais , Interações Hospedeiro-Patógeno , Humanos , Interações Hidrofóbicas e Hidrofílicas , Poliestirenos/química , Soro/microbiologiaAssuntos
Bactérias/efeitos dos fármacos , Infecção Hospitalar/microbiologia , Infecção Hospitalar/prevenção & controle , Surtos de Doenças , Transmissão de Doença Infecciosa/prevenção & controle , Farmacorresistência Bacteriana Múltipla , Controle de Infecções/métodos , Bactérias/isolamento & purificação , Brasil/epidemiologia , Infecção Hospitalar/epidemiologia , HumanosAssuntos
Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/enzimologia , Acinetobacter baumannii/isolamento & purificação , beta-Lactamases/genética , beta-Lactamases/metabolismo , Brasil , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Análise de Sequência de DNA , Homologia de Sequência de AminoácidosRESUMO
BACKGROUND: Contaminated surfaces play an important role in the transmission of certain pathogens that are responsible for healthcare-associated infections. Although previous studies have shown that meticillin-resistant Staphylococcus aureus (MRSA) can survive on dry surfaces at room temperature, no published data regarding vancomycin-intermediate S. aureus (VISA) are available to date. AIM: To compare the survival time on different types of surfaces, cell-surface hydrophobicity, adherence to abiotic surfaces and biofilm formation of meticillin-susceptible S. aureus (MSSA), MRSA and VISA. METHODS: Survival of the S. aureus strains was tested on latex, cotton fabric, vinyl flooring and formica. Cell-surface hydrophobicity was determined using the hydrocarbon interaction affinity method. Adhesion to abiotic surfaces was tested on granite, latex (gloves), glass, vinyl flooring and formica. Biofilm formation was evaluated at 6, 12, 24 and 48 h. FINDINGS: All of the samples survived on the vinyl flooring and formica for at least 40 days. VISA survived on both surfaces for more than 45 days. All of the strains were highly hydrophobic. VISA adhered to latex, vinyl flooring and formica. Biofilm formation increased for all of the tested strains within 6-24 h. CONCLUSION: VISA present high survival, adherence and cell-surface hydrophobicity. Therefore, as the treatment of patients with VISA is a significant challenge for clinicians, greater care with cleaning and disinfection of different types of surfaces in healthcare facilities is recommended because these may become important reservoirs of multi-resistant pathogens.
Assuntos
Infecção Hospitalar/microbiologia , Equipamentos e Provisões Hospitalares/microbiologia , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/patogenicidade , Proteínas de Bactérias/metabolismo , Endocardite Bacteriana/diagnóstico , Contaminação de Equipamentos , Hospitais , Humanos , Interações Hidrofóbicas e Hidrofílicas , Staphylococcus aureus Resistente à Meticilina , Sobrevida , Vancomicina , Resistência a VancomicinaRESUMO
The objective of this study was to identify mutations in the Quinolone Resistance Determining sources Regions (QRDR) of the gyrA, gyrB, parC, and parE genes and to determine if any of the qnr variants or the aac(6')-Ib-cr variant were present in strains of Salmonella spp. isolated in Brazil. A total of 126 Salmonella spp. strains from epidemic (n = 114) and poultry (n = 12) origin were evaluated. One hundred and twelve strains (88.8%) were resistant to nalidixic acid (NAL) and 29 (23.01%) showed a reduced susceptibility to ciprofloxacin (Cip). The mutations identified were substitutions limited to the QRDR of the gyrA gene in the codons for Serine 83, Aspartate 87 and Alanine 131. The sensitivity to NAL seems to be a good phenotypic indication of distinguishing mutated and non-mutated strains in the QRDR, however the double mutation in gyrA did not cause resistance to ciprofloxacin. The qnrA1 and qnrB19 genes were detected, respectively, in one epidemic strain of S. Enteritidis and one strain of S. Corvallis of poultry origin. Despite previous detection of qnr genes in Brazil, this is the first report of qnr gene detection in Salmonella, and also the first detection of qnrB19 gene in this country. The results alert for the continuous monitoring of quinolone resistance determinants in order to minimize the emergence and selection of Salmonella spp. strains showing reduced susceptibility or resistance to quinolones.
Assuntos
Antibacterianos/farmacologia , DNA Topoisomerases/genética , Farmacorresistência Bacteriana , Mutação , Quinolonas/farmacologia , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/genética , Animais , Brasil , Humanos , Testes de Sensibilidade Microbiana , Aves Domésticas , Infecções por Salmonella/microbiologia , Salmonelose Animal/microbiologiaRESUMO
The objective of this study was to identify mutations in the Quinolone Resistance Determining sources Regions (QRDR) of the gyrA, gyrB, parC, and parE genes and to determine if any of the qnr variants or the aac(6')-Ib-cr variant were present in strains of Salmonella spp. isolated in Brazil. A total of 126 Salmonella spp. strains from epidemic (n = 114) and poultry (n = 12) origin were evaluated. One hundred and twelve strains (88.8%) were resistant to nalidixic acid (NAL) and 29 (23.01%) showed a reduced susceptibility to ciprofloxacin (Cip). The mutations identified were substitutions limited to the QRDR of the gyrA gene in the codons for Serine 83, Aspartate 87 and Alanine 131. The sensitivity to NAL seems to be a good phenotypic indication of distinguishing mutated and nonmutated strains in the QRDR, however the double mutation in gyrA did not cause resistance to ciprofloxacin. The qnrA1 and qnrB19 genes were detected, respectively, in one epidemic strain of S. Enteritidis and one strain of S. Corvallis of poultry origin. Despite previous detection of qnr genes in Brazil, this is the first report of qnr gene detection in Salmonella, and also the first detection of qnrB19 gene in this country. The results alert for the continuous monitoring of quinolone resistance determinants in order to minimize the emergence and selection of Salmonella spp. strains showing reduced susceptibility or resistance to quinolones.(AU)
Assuntos
Salmonella enterica , DNA Topoisomerases Tipo II , Saúde Pública , Plasmídeos , FluoroquinolonasRESUMO
The objective of this study was to identify mutations in the Quinolone Resistance Determining sources Regions (QRDR) of the gyrA, gyrB, parC, and parE genes and to determine if any of the qnr variants or the aac(6')-Ib-cr variant were present in strains of Salmonella spp. isolated in Brazil. A total of 126 Salmonella spp. strains from epidemic (n = 114) and poultry (n = 12) origin were evaluated. One hundred and twelve strains (88.8%) were resistant to nalidixic acid (NAL) and 29 (23.01%) showed a reduced susceptibility to ciprofloxacin (Cip). The mutations identified were substitutions limited to the QRDR of the gyrA gene in the codons for Serine 83, Aspartate 87 and Alanine 131. The sensitivity to NAL seems to be a good phenotypic indication of distinguishing mutated and nonmutated strains in the QRDR, however the double mutation in gyrA did not cause resistance to ciprofloxacin. The qnrA1 and qnrB19 genes were detected, respectively, in one epidemic strain of S. Enteritidis and one strain of S. Corvallis of poultry origin. Despite previous detection of qnr genes in Brazil, this is the first report of qnr gene detection in Salmonella, and also the first detection of qnrB19 gene in this country. The results alert for the continuous monitoring of quinolone resistance determinants in order to minimize the emergence and selection of Salmonella spp. strains showing reduced susceptibility or resistance to quinolones.
Assuntos
Animais , Humanos , Antibacterianos/farmacologia , DNA Topoisomerases/genética , Farmacorresistência Bacteriana , Mutação , Quinolonas/farmacologia , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/genética , Brasil , Testes de Sensibilidade Microbiana , Aves Domésticas , Salmonelose Animal/microbiologia , Infecções por Salmonella/microbiologiaRESUMO
AIMS: The objective of this study was to assess the antimicrobial efficacy of alcohol-based hand gels according to European Norm 1500 (EN 1500). METHODS AND RESULTS: We assessed the antimicrobial efficacy of 12 alcohol-based hand gels produced in Brazil, containing 70% w/w or v/v ethyl alcohol as the active ingredient, according to EN 1500, with a 30-s application. In addition, 70% w/w ethyl alcohol and three alcohol-based hand rubs commonly used in Europe and effective according to EN 1500 were also tested. Eight of 12 (67%) alcohol-based hand gels produced in Brazil failed by EN 1500. In contrast, 70% w/w ethyl alcohol and European alcohol-based hand rubs were approved by EN 1500. CONCLUSIONS: In this study, the majority of Brazilian alcohol-based hand gels showed limited efficacy on hand hygiene within 30 s. SIGNIFICANCE AND IMPACT OF THE STUDY: The findings of this study may be used as an important argument to motivate Brazilian manufacturers to improve the antimicrobial efficacy of alcohol-based hand gels, because it is prudent to suppose that alcohol-based hand gels can be recommended for use in healthcare settings only if they show antimicrobial activity at least similar to that of alcohol-based liquid preparations, including the traditional 70% w/w ethyl alcohol.