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Abstract Neonatal sepsis continues to be a major cause of morbidity and mortality worldwide. Coagulase-negative staphylococci (CoNS), commonly found on the skin, being the main agents isolated. The aim of this study was to evaluate CoNS isolated from blood cultures of newborn (NB) infants. The study took place between 2014 and 2016/2017 in a tertiary hospital in southern Brazil. Using the VITEK 2 system (bioMérieux, Marcy l'Etoile, France), the microorganisms were identified and had their sensitivity profiles determined. The minimum inhibitory concentrations of linezolid, tigecycline, and vancomycin were also determined. The clinical parameters and mortality rates of NBs were evaluated. From January to December 2014, 176 CoNS isolates were obtained from 131 patients and from June 2016 to July 2017, 120 CoNS isolates were obtained from 79 patients. Staphylococcus epidermidis was most prevalent in both periods. Resistance rates increased between 2014 and 2016/2017, especially against ciprofloxacin (52.27% and 73.11%, p = 0.0004), erythromycin (51.40% and 68.07%, p = 0.0054), gentamicin (50.59% and 67.23%, p = 0.0052), and penicillin (71.3% and 99.17%, p = 0.0001), respectively. With 100% susceptibility to linezolid, tigecycline, and vancomycin in both periods and methodologies tested. In 2014, 53.44% of the NBs received antibiotic therapy, and of these, 77.14% used a catheter; in 2016/2017, these were 78.48% and 95.16%, respectively. Regarding laboratory tests, a hemogram was ineffective, since patients with sepsis presented normal reference values. In 2014 and 2016/17, 15.71% and 17.74% of the NBs died, respectively. S. epidermidis was the predominant microorganism, related to catheter use in most cases. The resistance rates have increased over time, demonstrating the importance of adopting control and prevention measures in this hospital. CoNS are responsible for a significant neonatal sepsis mortality rate in infants.
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Humanos , Masculino , Feminino , Recém-Nascido , Síndrome da Pele Escaldada Estafilocócica/patologia , Recém-Nascido , Coagulase/efeitos adversos , Pele , Staphylococcus epidermidis/patogenicidade , Testes de Sensibilidade Microbiana/instrumentação , Mortalidade , Sepse/patologia , Hemocultura/classificação , Hemocultura/instrumentação , HospitaisRESUMO
The repositioning of approved drugs is atopic of interest for the academy and the pharmaceutical industry. The synergistic combination of these drugs can be successful in the treatment of infections caused by resistant bacteria. This study aimed to assess the in vitro synergistic antibacterial activity of sertraline and disulfiram and their interaction with ciprofloxacin and sulfamethoxazole/trimethoprim. We determined the minimum inhibitory concentration, the minimum bactericidal concentration and the fractional inhibitory concentration index. Eighteen bacterial strains were used, being nine American Type Culture Collection reference strains and nine multidrug resistant clinical isolates. Synergy was detected between sertraline and disulfiram against a strain of Staphylococcus aureusATCC 25923 and a clinical isolate of S. aureus. When associated to sulfamethoxazole/trimethoprim and ciprofloxacin, sertraline and disulfiram showed eight synergistic events, which occurred against three different standard strains and two multidrug resistant clinical isolates. When the minimum bactericidal concentration was determined, the bactericidal activity of sertraline was enhanced with disulfiram. Our results suggest that these drugs, widely used to treat depression and chronic alcoholism, have antibacterial potential individually, in association, and combined with antimicrobials, what makes their repositioning a promising therapeutic alternative for the effective treatment of infections caused by multidrug resistant bacteria.
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INTRODUCTION: Coagulase-negative staphylococci (CoNS) are a frequent cause of bacteremia, especially in neonates. The major virulence determinant in CoNS is the ability to produce biofilms, which is conferred by the icaADBC genes. This study aimed to assess different methods for the detection of biofilm formation in 176 CoNS isolates from blood cultures of newborns. METHODS: The presence of the icaACD genes was assessed by polymerase chain reaction (PCR), and biofilm formation was assessed on congo red agar (CRA), by the tube method (TM), and on tissue culture plates (TCP). RESULTS: Of the 176 CoNS isolates, 30.1% expressed icaACD and 11.4% expressed icaAD. The CRA assay and TM showed that 42% and 38.6% of the isolates were biofilm producing, respectively. On TCP, 40.9% of the isolates produced biofilms; 21% were weakly adherent and 19.9% were strongly adherent. When compared to the gold standard technique (PCR), the CRAassay showed 79% sensitivity and 84% specificity (kappa = 0.64), TM showed 78% sensitivity and 89% specificity (kappa = 0.68), and TCP showed 99% sensitivity and 100% specificity (kappa = 0.99). CONCLUSIONS: In this study, ~42% of CoNS isolates produced biofilms, and the presence of icaACD was associated with a greater capacity to form biofilms. Compared to the other phenotypic methodologies, TCP is an ideal procedure for routine laboratory use.
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Bacteriemia/microbiologia , Biofilmes/crescimento & desenvolvimento , Infecções Estafilocócicas/diagnóstico , Staphylococcus/isolamento & purificação , Vermelho Congo , Técnicas de Cultura , Genótipo , Humanos , Recém-Nascido , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Infecções Estafilocócicas/microbiologia , Staphylococcus/genéticaRESUMO
Abstract INTRODUCTION: Coagulase-negative staphylococci (CoNS) are a frequent cause of bacteremia, especially in neonates. The major virulence determinant in CoNS is the ability to produce biofilms, which is conferred by the icaADBC genes. This study aimed to assess different methods for the detection of biofilm formation in 176 CoNS isolates from blood cultures of newborns. METHODS: The presence of the icaACD genes was assessed by polymerase chain reaction (PCR), and biofilm formation was assessed on congo red agar (CRA), by the tube method (TM), and on tissue culture plates (TCP). RESULTS: Of the 176 CoNS isolates, 30.1% expressed icaACD and 11.4% expressed icaAD. The CRA assay and TM showed that 42% and 38.6% of the isolates were biofilm producing, respectively. On TCP, 40.9% of the isolates produced biofilms; 21% were weakly adherent and 19.9% were strongly adherent. When compared to the gold standard technique (PCR), the CRAassay showed 79% sensitivity and 84% specificity (kappa = 0.64), TM showed 78% sensitivity and 89% specificity (kappa = 0.68), and TCP showed 99% sensitivity and 100% specificity (kappa = 0.99). CONCLUSIONS: In this study, ~42% of CoNS isolates produced biofilms, and the presence of icaACD was associated with a greater capacity to form biofilms. Compared to the other phenotypic methodologies, TCP is an ideal procedure for routine laboratory use.
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Humanos , Recém-Nascido , Infecções Estafilocócicas/diagnóstico , Staphylococcus/isolamento & purificação , Bacteriemia/microbiologia , Biofilmes/crescimento & desenvolvimento , Infecções Estafilocócicas/microbiologia , Staphylococcus/genética , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Vermelho Congo , Técnicas de Cultura , GenótipoRESUMO
INTRODUCTION: The spread of multidrug-resistant Gram-negative bacilli is a health threat, limiting therapeutic options and increasing morbimortality rates. METHODS: This study aimed to evaluate the antimicrobial susceptibility profile of 1805 Klebsiella pneumoniae isolates collected from Hospital Universitário de Santa Maria between January 2015 and December 2016. RESULTS: Resistance to colistin (239.3%), meropenem (74.2%), ciprofloxacin (68%), gentamicin (35.1%), tigecycline (33.9%), imipenem (29.7%), ertapenem (26.8%), and amikacin (21.4%) was found increased. CONCLUSIONS: Infection control measures in the hospitals are necessary for reducing the spread of multidrug-resistant microorganisms and preventing efficacy loss of these drugs.
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Antibacterianos/farmacologia , Hospitais Universitários/estatística & dados numéricos , Klebsiella pneumoniae/efeitos dos fármacos , Adolescente , Adulto , Brasil , Criança , Pré-Escolar , Farmacorresistência Bacteriana , Feminino , Humanos , Lactente , Recém-Nascido , Klebsiella pneumoniae/isolamento & purificação , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto JovemRESUMO
Abstract INTRODUCTION The spread of multidrug-resistant Gram-negative bacilli is a health threat, limiting therapeutic options and increasing morbimortality rates. METHODS: This study aimed to evaluate the antimicrobial susceptibility profile of 1805 Klebsiella pneumoniae isolates collected from Hospital Universitário de Santa Maria between January 2015 and December 2016. RESULTS: Resistance to colistin (239.3%), meropenem (74.2%), ciprofloxacin (68%), gentamicin (35.1%), tigecycline (33.9%), imipenem (29.7%), ertapenem (26.8%), and amikacin (21.4%) was found increased. CONCLUSIONS: Infection control measures in the hospitals are necessary for reducing the spread of multidrug-resistant microorganisms and preventing efficacy loss of these drugs.
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Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Adulto Jovem , Hospitais Universitários/estatística & dados numéricos , Klebsiella pneumoniae/efeitos dos fármacos , Antibacterianos/farmacologia , Brasil , Testes de Sensibilidade Microbiana , Estudos Retrospectivos , Farmacorresistência Bacteriana , Klebsiella pneumoniae/isolamento & purificação , Pessoa de Meia-IdadeRESUMO
Abstract The treatment of infections caused by resistant microorganisms represents a big challenge in healthcare due to limited treatment options. For this reason, the discovery of new active substances which are able to perform innovative and selective actions is of great impact nowadays. Statins and triazenes (TZC) have consolidated as a promising class of compounds, characterized by the expressive biological activity, especially antimicrobial activities. The aim of this study was to assess the in vitro synergistic antibacterial effect of the association of statins and a new TZC complex {[1-(4-bromophenyl)-3-phenyltriazene N 3-oxide-κ 2 N 1,O 4](dimethylbenzylamine-κ 2 C 1,N 4)palladium(II)} (Pd(DMBA)LBr) against American Type Culture Collection (ATCC) strains and clinical isolates. The complex and the statins showed bacterial activity of all tested strains and clinical isolates, evidencing that TZC complexion with metals can be promising. Simvastatin showed synergy when associated to the complex (FICI≤0.5), being the minimum inhibitory concentration (MIC) of 16 µg mL-1 found in 6 samples. Thus, it is possible to infer that the association between Pd(DMBA)LBr and simvastatin consists of an alternative to increase the pontential of these compounds, since statins have low toxicity.
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Triazenos/efeitos adversos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Sinvastatina , Composição de MedicamentosRESUMO
INTRODUCTION: The rapid global spread of carbapenem-resistant Enterobacteriaceae (CRE) is a threat to the health system. METHODS: We evaluated the antimicrobial susceptibility profiles of 70 CRE isolated in a tertiary hospital in Brazil between August and December 2015, and determined their resistance mechanisms. RESULTS: The most prevalent microorganism was Klebsiella pneumoniae (95.7%); it showed high-level resistance to carbapenems (>98%), with sensitivity to colistin (91.4%) and amikacin (98.6%). The bla KPC gene was detected in 80% of the CRE isolates. CONCLUSIONS: Evaluation of bacterial resistance contributes to an appropriate treatment, and the reduction of morbimortality and dissemination of resistance.
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Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Infecções por Enterobacteriaceae/epidemiologia , Centros de Atenção Terciária/estatística & dados numéricos , Adolescente , Adulto , Anti-Infecciosos/farmacologia , Brasil/epidemiologia , Criança , Pré-Escolar , Citrobacter freundii/isolamento & purificação , Infecção Hospitalar/epidemiologia , Enterobacter cloacae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Escherichia coli/isolamento & purificação , Feminino , Genótipo , Humanos , Lactente , Klebsiella pneumoniae/isolamento & purificação , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Adulto JovemRESUMO
Abstract INTRODUCTION: The rapid global spread of carbapenem-resistant Enterobacteriaceae (CRE) is a threat to the health system. METHODS: We evaluated the antimicrobial susceptibility profiles of 70 CRE isolated in a tertiary hospital in Brazil between August and December 2015, and determined their resistance mechanisms. RESULTS: The most prevalent microorganism was Klebsiella pneumoniae (95.7%); it showed high-level resistance to carbapenems (>98%), with sensitivity to colistin (91.4%) and amikacin (98.6%). The bla KPC gene was detected in 80% of the CRE isolates. CONCLUSIONS: Evaluation of bacterial resistance contributes to an appropriate treatment, and the reduction of morbimortality and dissemination of resistance.
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Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Adulto Jovem , Infecções por Enterobacteriaceae/epidemiologia , Centros de Atenção Terciária/estatística & dados numéricos , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Brasil/epidemiologia , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Infecção Hospitalar/epidemiologia , Enterobacter cloacae/isolamento & purificação , Citrobacter freundii/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Escherichia coli/isolamento & purificação , Genótipo , Klebsiella pneumoniae/isolamento & purificação , Anti-Infecciosos/farmacologia , Pessoa de Meia-IdadeRESUMO
INTRODUCTION:: In this study, we used phenotypic methods to screen carbapenem-resistant Enterobacteriaceae (CREs) and evaluated their antimicrobial sensitivity profile. METHODS:: One hundred and seventy-eight CREs were isolated at a university hospital in south Brazil in a one-year period. Samples were assessed using disk diffusion tests with inhibitors of ß-lactamases such as phenylboronic acid (AFB), cloxacillin (CLOXA), and ethylenediaminetetraacetic acid (EDTA). Strains with differences in zone diameters ≥ 5mm for disks supplemented or not were considered producers of carbapenemases. RESULTS:: Klebsiella pneumoniae was the most prevalent CRE, which appeared in 80.3% cases (n = 143). Among clinical materials, the rectal swab was responsible for 43.4% of the isolations (n = 62), followed by urine (18.9%; n = 27). Among the CREs identified in this study, the growth of 56.7% (n = 101) isolates, which were putative producers of Klebsiella pneumoniae carbapenemase (KPC), were inhibited by AFB, whereas 7.3% (n = 13) isolates were inhibited by both AFB and CLOXA and were considered as putative producers of plasmid-mediated AmpC; approximately 3.4% (n = 6) were inhibited by EDTA, which possibly produced metallo-ß-lactamase. Lastly, 32.6% (n = 58) cases showed negative results for AFB, CLOXA, and EDTA sensitivity, and represented another class of ß-lactamases and/or mechanism of resistance. CONCLUSIONS:: Phenotypic screening of CREs is important for clinical laboratories that monitor outbreaks of resistant microbes. Phenotypic tests that use carbapenemase inhibitors and enhancers such as AFB, CLOXA, and EDTA are necessary since they are good screening methods for the detection of carbapenemases.