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1.
Pan Afr Med J ; 39: 84, 2021.
Artigo em Francês | MEDLINE | ID: mdl-34466186

RESUMO

The treatment of acute osteomyelitis is becoming more challenging since the emergence of community-acquired methicillin-resistant Staphylococcus aureus. We collected data on all patients with acute osteomyelitis caused by this germ over a period of 21 years (January 1995-December 2016) and we analyzed the peculiarities of this disorder. Our case series includes 15 children, with an average age of 9 years. All patients had affected lower limb. Local trauma was reported in 8 cases and skin carriage in 4 cases. Acute onset was reported in 12 cases associated with pseudo-paralysis of the affected limb. One patient had Staphylococcus aureus pulmonary infection with signs of septicopyemia. Blood culture was positive in 8 cases. In one case PCR assay for detection of Panton-Valentine leukocidin was performed with positive result. All these patients underwent surgical debridement and received secondarily adapted empirical antibiotic therapy. Outcome was good in 8 cases and poor in the other cases, with transition to a chronic state in 6 cases and one case of death. Pathological fracture was reported in 3 cases. Osteomyelitis cause by community-acquired methicillin-resistant Staphylococcus aureus is associated with a pejorative outcome. Recognizing the clinical and paraclinical signs of these infections is essential for a specific and early therapeutic management.


Assuntos
Infecções Comunitárias Adquiridas/diagnóstico , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Osteomielite/diagnóstico , Infecções Estafilocócicas/diagnóstico , Doença Aguda , Adolescente , Antibacterianos/administração & dosagem , Criança , Pré-Escolar , Terapia Combinada , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/terapia , Desbridamento/métodos , Feminino , Humanos , Masculino , Osteomielite/microbiologia , Osteomielite/terapia , Estudos Retrospectivos , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/terapia
2.
J Med Microbiol ; 70(8)2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34338626

RESUMO

Introduction. Biofilm formation is a major virulence factor associated with Staphylococcus aureus infections. However, the influence of plasma proteins on biofilm formation of clinical isolates in vitro remains unclear.Hypotheses. We hypothesized that coating surfaces with plasma proteins might induce biofilm formation by S. aureus of different clonal lineages.Aim. To evaluate biofilm production by clinical S. aureus isolates of different clonal lineages isolated in Rio de Janeiro hospitals and investigated the presence of biofilm-associated genes.Methodology. This study assessed biofilm production of 60 S. aureus isolates in polystyrene microtitre plates with and without fibrinogen or fibronectin. The biochemical composition of the biofilm matrices was determined and the biofilm formation on fibrinogen-coated surfaces was also evaluated by confocal laser scanning microscopy. The presence of biofilm-related genes was detected by PCR, and the typing and functionality of agr operon was also evaluated.Results. Most of the isolates (45 %) were weak biofilm producers or non-producers. However, most of them presented a significant increase in biofilm production on plates covered with plasma proteins. There was no significant difference in biofilm formation between methicillin-resistant and -susceptible S. aureus isolates, or between different clonal lineages, except for ST30-IV (weak producers) and ST239-III (strong producers). The fnbB gene was associated with higher biofilm production.Conclusion. An increase in biofilm production in the presence of plasma proteins highlights the importance of investigating biofilm formation by S. aureus clinical isolates under different conditions since this virulence factor contributes to persistent infections and increased resistance to antimicrobials.


Assuntos
Biofilmes/crescimento & desenvolvimento , Fibrinogênio , Fibronectinas , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Staphylococcus aureus/patogenicidade , Adesinas Bacterianas/genética , Aderência Bacteriana/genética , Proteínas de Bactérias/genética , Genes Bacterianos , Genótipo , Humanos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/fisiologia , Óperon , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/fisiologia , Transativadores/genética
3.
Eur J Med Res ; 26(1): 91, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34380556

RESUMO

We present a case of bacterial endocarditis with both methicillin-sensitive and methicillin-resistant Staphylococcus aureus, which based on typing, originated from two distinct clones. Such a case may be misinterpreted by microbiology lab automation to be a monoclonal multi-drug resistant Staphylococcus aureus, while simple microbiology techniques will instantly reveal distinct clonality.


Assuntos
Endocardite Bacteriana/microbiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas/microbiologia , Adulto , Coinfecção , Farmacorresistência Bacteriana , Endocardite Bacteriana/patologia , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Infecções Estafilocócicas/patologia
4.
Int J Mol Sci ; 22(12)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207373

RESUMO

A nucleic acid aptamer that specifically recognizes methicillin-resistant Staphylococcus aureus (MRSA) has been immobilized on magnetic nanoparticles to capture the target bacteria prior to mass spectrometry analysis. After the MRSA species were captured, they were further eluted from the nanoparticles and identified using matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS). The combination of aptamer-based capture/enrichment and MS analysis of microorganisms took advantage of the selectivity of both techniques and should enhance the accuracy of MRSA identification. The capture and elution efficiencies for MRSA were optimized by examining factors such as incubation time, temperature, and elution solvents. The aptamer-modified magnetic nanoparticles showed a capture rate of more than 90% under the optimized condition, whereas the capture rates were less than 11% for non-target bacteria. The as-prepared nanoparticles exhibited only a 5% decrease in the capture rate and a 9% decrease in the elution rate after 10 successive cycles of utilization. Most importantly, the aptamer-modified nanoparticles revealed an excellent selectivity towards MRSA in bacterial mixtures. The capture of MRSA at a concentration of 102 CFU/mL remained at a good percentage of 82% even when the other two species were at 104 times higher concentration (106 CFU/mL). Further, the eluted MRSA bacteria were successfully identified using MALDI mass spectrometry.


Assuntos
Aptâmeros de Nucleotídeos/química , Nanopartículas de Magnetita/química , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Staphylococcus aureus Resistente à Meticilina/citologia , Técnica de Seleção de Aptâmeros/métodos
6.
Artigo em Inglês | MEDLINE | ID: mdl-34094618

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) remains one of the leading causes of both nosocomial and community infections worldwide. In the Philippines, MRSA rates have remained above 50% since 2010, but resistance to other antibiotics, including vancomycin, is low. The MRSA burden can be partially attributed to pathogen-specific characteristics of the circulating clones, but little was known about the S. aureus clones circulating in the Philippines. We sequenced the whole genomes of 116 S. aureus isolates collected in 2013-2014 within the Antimicrobial Resistance Surveillance Program. The multilocus sequence type, spa type, SCCmec type, presence of antimicrobial resistance (AMR) determinants and virulence genes and relatedness between the isolates were all derived from the sequence data. The concordance between phenotypic and genotypic resistance was also determined. The MRSA population in the Philippines comprised a limited number of genetic clones, including several international epidemic clones, such as CC30-spa-t019-SCCmec-IV-PVL+, CC5-SCCmec-typeIV and ST239-spa-t030-SCCmec-typeIII. The CC30 genomes were related to the South-West Pacific clone but formed a distinct, diverse lineage, with evidence of global dissemination. We showed independent acquisition of resistance to sulfamethoxazole/trimethoprim in various locations and genetic clones but mostly in paediatric patients with invasive infections. The concordance between phenotypic and genotypic resistance was 99.68% overall for eight antibiotics in seven classes. We have made the first comprehensive genomic survey of S. aureus in the Philippines, which bridges the gap in genomic data from the Western Pacific Region and will constitute the genetic background for contextualizing prospective surveillance.


Assuntos
Staphylococcus aureus Resistente à Meticilina/genética , Infecções Estafilocócicas/microbiologia , Genômica , Humanos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Filipinas/epidemiologia , Infecções Estafilocócicas/epidemiologia
7.
J Mater Chem B ; 9(23): 4735-4745, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34095948

RESUMO

Large bone defects face a high risk of infection, which can also lead to bone homeostasis disorders. This seriously hinders the bone healing process; therefore, the help of a dual-functional scaffold that has both anti-infection and bone-homeostasis-regulating capacities is needed in the treatment of infected bone defects. In this study, a 3D printed dual-functional scaffold composed of poly-ε-caprolactone (PCL), mesoporous bioactive glasses (MBG), and gallium (Ga) was produced. In vitro experiments demonstrated the excellent antibacterial ability of the PCL/MBG/Ga scaffold against methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli). The scaffold also significantly inhibited osteoclastic activity and promoted osteogenic differentiation. Furthermore, a rabbit model with an infected bone defect in the radius was used to evaluate the in vivo bone healing capability of PCL/MBG/Ga. The results demonstrate that the PCL/MBG/Ga scaffold can significantly accelerate bone healing and prevent bone resorption, suggesting its potential for application in repairing infected bone defects.


Assuntos
Anti-Infecciosos/uso terapêutico , Osso e Ossos/patologia , Infecções por Escherichia coli/tratamento farmacológico , Gálio/química , Homeostase , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Impressão Tridimensional , Infecções Estafilocócicas/tratamento farmacológico , Animais , Regeneração Óssea , Osso e Ossos/microbiologia , Coelhos , Infecções Estafilocócicas/microbiologia , Tecidos Suporte , Cicatrização
8.
J Vet Diagn Invest ; 33(4): 655-663, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34075814

RESUMO

The use of oral fluid (OF) to detect zoonotic pathogens in pigs has been only scarcely assessed. We evaluated OF as a potential specimen for detection by culture of methicillin-resistant Staphylococcus aureus (MRSA) and Yersinia enterocolitica, and the detection of antibodies against Salmonella spp. and hepatitis E virus (HEV) using commercial ELISAs. Samples from 33 pig farms were collected at the beginning and end of the fattening period. Results of the OF samples were compared with the results of serum samples and nasal swabs from individual pigs and pen floor fecal samples, using the Cohen kappa (κ) and the McNemar test. For Salmonella spp. antibodies, OF samples were negative, although the corresponding serum samples were positive. The detection of HEV antibodies in sera and OF had agreement at the first sampling, and poor and significant agreement at the second sampling (κ = 0.185, McNemar p = 0.238; κ = 0.088, McNemar p < 0.001). At both sampling times, the detection of MRSA in nasal swabs and OF showed agreement (κ = 0.466, McNemar p = 0.077; κ = 0.603, McNemar p = 1); agreement was seen for the detection of Y. enterocolitica in fecal and OF samples (κ = 0.012, McNemar p = 0.868; κ = 0.082, McNemar p = 0.061, respectively). According to the McNemar test, the use of pen-based OFs is more feasible for the detection of MRSA and Y. enterocolitica by culture than is detection of antibodies by commercial ELISA.


Assuntos
Hepatite E/veterinária , Saliva/microbiologia , Salmonelose Animal/epidemiologia , Infecções Estafilocócicas/veterinária , Doenças dos Suínos/epidemiologia , Yersiniose/veterinária , Animais , Hepatite E/diagnóstico , Hepatite E/epidemiologia , Hepatite E/microbiologia , Vírus da Hepatite E/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Prevalência , Salmonella/isolamento & purificação , Salmonelose Animal/diagnóstico , Salmonelose Animal/microbiologia , Estudos Soroepidemiológicos , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Sus scrofa , Suínos , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/microbiologia , Suíça/epidemiologia , Yersiniose/diagnóstico , Yersiniose/epidemiologia , Yersiniose/microbiologia , Yersinia enterocolitica/isolamento & purificação
9.
BMC Infect Dis ; 21(1): 578, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34130629

RESUMO

BACKGROUND: Antibiotic Resistance is an imminent global public health threat. Antibiotic resistance emerged in healthcare settings and has now moved on to the community settings. This study was conducted to identify the rates of asymptomatic colonization with selected antibiotic resistant organisms, (Methicillin Resistant Staphylococcus aureus (MRSA), Extended Spectrum Beta Lactamase (ESBL) producing Escherichia coli and Klebsiella spp and carbapenem resistant E.coli and Klebsiella spp) - among a group of university students in Sri Lanka. Identification of genetic determinants of MRSA and ESBL was an additional objective of the study. METHODS: A self - collected nasal swab and a peri-rectal swab collected after passing stools were obtained. Routine microbiological methods were used for the isolation S.aureus from the nasal swab and E.coli and Klebsiella species from the peri-rectal swab. Antibiotic sensitivity testing was performed as recommended by clinical and laboratory standard institute (CLSI). Three (3) genes that are responsible for ESBL production; blaCTX-M, blaSHV, and blaTEM were tested using previously described primers and PCR procedures. Identification of MecA and PVL genes attributed to MRSA was also done with PCR. RESULTS: A total of 322 participants between 21 and 28 years were recruited representing 5 different faculties of study. Seventy one (22.0%) were colonized with S.aureus and 14 among them with MRSA, making the MRSA colonization rate of 4.3%. Forty five (15%) of the participants were colonized with an ESBL producing E.coli or Klebsiella spp. No one was colonized with carbapenem resistant E.coli or Klebsiella species. Of the 45 ESBL producers the commonest genetic determinant identified was blaCTX-M (n = 36), while 16 isolates had blaTEM and 7 had blaSHV. Similarly, of the 14 isolates identified as MRSA, 3 (21.4%) were found to be PVL positive while 11 (78.6%) were MecA positive. CONCLUSIONS: A high rate of colonization with ESBL producing E.coli and Klebsiella species was noted in our study group.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Farmacorresistência Bacteriana , Universidades , Adulto , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Carbapenêmicos/uso terapêutico , Estudos de Coortes , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Feminino , Humanos , Klebsiella/isolamento & purificação , Infecções por Klebsiella/microbiologia , Masculino , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Sri Lanka , Infecções Estafilocócicas/microbiologia , Estudantes , Adulto Jovem , beta-Lactamases/genética
10.
BMC Infect Dis ; 21(1): 589, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34154550

RESUMO

BACKGROUND: Bloodstream infections due to Staphylococcus aureus cause significant patient morbidity and mortality worldwide. Of major concern is the emergence and spread of methicillin-resistant S. aureus (MRSA) in bloodstream infections, which are associated with therapeutic failure and increased mortality. METHODS: We generated high quality draft genomes from 323 S. aureus blood culture isolates from patients diagnosed with bloodstream infection at the Dartmouth-Hitchcock Medical Center, New Hampshire, USA in 2010-2018. RESULTS: In silico detection of antimicrobial resistance genes revealed that 133/323 isolates (41.18%) carry horizontally acquired genes conferring resistance to at least three antimicrobial classes, with resistance determinants for aminoglycosides, beta-lactams and macrolides being the most prevalent. The most common resistance genes were blaZ and mecA, which were found in 262/323 (81.11%) and 104/323 (32.20%) isolates, respectively. Majority of the MRSA (102/105 isolates or 97.14%) identified using in vitro screening were related to two clonal complexes (CC) 5 and 8. The two CCs emerged in the New Hampshire population at separate times. We estimated that the time to the most recent common ancestor of CC5 was 1973 (95% highest posterior density (HPD) intervals: 1966-1979) and 1946 for CC8 (95% HPD intervals: 1924-1959). The effective population size of CC8 increased until the late 1960s when it started to level off until late 2000s. The levelling off of CC8 in 1968 coincided with the acquisition of SCCmec Type IV in majority of the strains. The plateau in CC8 also coincided with the acceleration in the population growth of CC5 carrying SCCmec Type II in the early 1970s, which eventually leveled off in the early 1990s. Lastly, we found evidence for frequent recombination in the two clones during their recent clonal expansion, which has likely contributed to their success in the population. CONCLUSIONS: We conclude that the S. aureus population was shaped mainly by the clonal expansion, recombination and co-dominance of two major MRSA clones in the last five decades in New Hampshire, USA. These results have important implications on the development of effective and robust strategies for intervention, control and treatment of life-threatening bloodstream infections.


Assuntos
Staphylococcus aureus Resistente à Meticilina/genética , Sepse/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/genética , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana , Genômica , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Sepse/tratamento farmacológico , Sepse/virologia , Infecções Estafilocócicas/virologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação
11.
Infect Dis Now ; 51(3): 304-307, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33934810

RESUMO

OBJECTIVES: To describe the efficacy and safety of prolonged cefazolin course for Staphylococcus infection and the emergence of multidrug-resistant bacteria carriage after treatment. METHODS: Monocentric retrospective cohort study of patients hospitalized for blood stream infections (BSI) and osteoarticular infections (OAI) by methicillin susceptible staphylococcal species treated with cefazolin from January 2015 to July 2017. Rectal and nasal swabs were performed at cefazolin initiation and end of treatment to detect respectively methicillin resistant Staphylococcus aureus (MRSA) and extended-spectrum beta-lactamase (ESBL) producing bacteria. RESULTS: Fifty-eight patients were included, 41 had a bacteremia including 22 endocarditis and 22 OAI. Mean duration of treatment was 21.5 days at a mean daily dose of 6.5g/d. Fifty-five (94.5%) received combination therapy. Fifty-two (89.7%) of patients achieved bacteriological cure. Four patients were ESBL carriers at inclusion. No additional ESBL or MRSA were detected by end of treatment. CONCLUSION: Cefazolin appears as an effective and safe treatment for BSI or osteoarticular infection and does not appear to select MRSA or ESBL.


Assuntos
Antibacterianos/administração & dosagem , Cefazolina/administração & dosagem , Farmacorresistência Bacteriana Múltipla , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas/tratamento farmacológico , Idoso , Bacteriemia/tratamento farmacológico , Doenças Ósseas Infecciosas/tratamento farmacológico , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Cloxacilina/administração & dosagem , Endocardite Bacteriana/tratamento farmacológico , Feminino , Humanos , Masculino , Meticilina/uso terapêutico , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Pessoa de Meia-Idade , Estudos Retrospectivos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação
12.
Int J Infect Dis ; 107: 69-71, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33878463

RESUMO

The activities of dalbavancin and comparator agents were evaluated against Staphylococcus aureus isolated from the lower respiratory tract of cystic fibrosis (CF) and non-CF patients with pneumonia. Bacterial isolates (n = 357) were collected from CF patients in 36 medical centers worldwide (2018-2019) and susceptibility tested using reference broth microdilution. Susceptibility results from these isolates were compared with those for 725 S. aureus isolates consecutively collected from non-CF patients with pneumonia from the same medical centers over the same period. Only isolates determined to be the probable cause of pneumonia were included in the study. Susceptibility profiles were very similar among isolates from CF and non-CF patients. Dalbavancin exhibited potent activity (MIC50/90, 0.03/0.03 mg/L) and complete coverage (100.0% susceptibility) against isolates from CF and non-CF patients. Ceftaroline (MIC50/90, 0.25/1 mg/L) was active against 97.8% and 98.1% of isolates from CF and non-CF patients, respectively. Oxacillin resistance (MRSA) rates were 27.7% among CF and 28.7% among non-CF patients. Among MRSA isolates from CF/non-CF patients (n = 99/208), susceptibility to ceftaroline, clindamycin, levofloxacin, and tetracycline were 91.9%/93.3%, 58.6%/64.4%, 40.4%/29.3%, and 83.8%/89.4%, respectively. Dalbavancin demonstrated high potency against S. aureus from CF and non-CF patients and may represent a valuable treatment option for CF patients with MRSA pulmonary infection.


Assuntos
Antibacterianos/uso terapêutico , Fibrose Cística/microbiologia , Pneumonia Estafilocócica/tratamento farmacológico , Staphylococcus aureus/isolamento & purificação , Teicoplanina/análogos & derivados , Cefalosporinas/uso terapêutico , Clindamicina/uso terapêutico , Farmacorresistência Bacteriana , Humanos , Levofloxacino/uso terapêutico , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Oxacilina/uso terapêutico , Pneumonia Estafilocócica/microbiologia , Teicoplanina/uso terapêutico , Tetraciclina/uso terapêutico
13.
BMC Vet Res ; 17(1): 177, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33902574

RESUMO

BACKGROUND: Staphylococcus aureus (S. aureus), especially methicillin-resistant Staphylococcus aureus (MRSA), is considered a common zoonotic pathogen, causing severe infections. The objective of this study was to investigate the antimicrobial susceptibility, resistance genes and molecular epidemiology among MRSA and methicillin-susceptible Staphylococcus aureus (MSSA) isolated from food animals in Sichuan Province, China. METHODS: This study was conducted on 236 S. aureus isolates. All isolates were subjected to antimicrobial susceptibility testing by using a standard microbroth dilution method. The Polymerase Chain Reaction (PCR) was performed to identify genes encoding the ß-lactams resistance (blaZ, mecA), macrolides (ermA, ermB, ermC) and aminoglycosides (aacA-aphD). The molecular structures and genomic relatedness of MRSA isolates were determined by staphylococcal chromosome cassette mec (SCCmec) typing and pulsed-field gel electrophoresis (PFGE), respectively. RESULTS: Among 236 isolates, 24 (10.17 %) were recognized as MRSA. MRSA isolates showed different resistance rates to 11 antimicrobials ranging from 33.33 to 100 %, while for MSSA isolates the rates varied from 8.02 to 91.51 %. Multi-drug resistance phenotype was found in all MRSA isolates. The ermC gene encoding macrolides-lincosamides-streptogramin B was the most prevalent gene detected in 87.29 % of the S. aureus isolates, followed by ermB (83.05 %), blaZ (63.98 %), aacA-aphD (44.07 %), ermA (11.44 %) and mecA (11.02 %) genes. The prevalence of resistance genes in MRSA isolates was significantly higher than that of MSSA. Regarding the molecular morphology, SCCmec III (12/24, 50 %) was the most common SCCmec type. Furthermore, the PFGE typing showed that 24 MRSA were divided into 15 cluster groups (A to O), the major pulsotype J encompassed 25 % of MRSA isolates. CONCLUSIONS: The S. aureus isolates from food animals in Sichuan province of China have severe antimicrobials resistance with various resistance genes, especially MRSA isolates. Additionally, the genetic pool of MRSA isolates is diverse and complex, and further investigation is necessary.


Assuntos
Staphylococcus aureus Resistente à Meticilina/genética , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/genética , Animais , Antibacterianos/farmacologia , Bovinos , Galinhas , China/epidemiologia , Farmacorresistência Bacteriana/genética , Patos , Meticilina/farmacologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana/veterinária , Epidemiologia Molecular , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Suínos
14.
Arch Microbiol ; 203(6): 3295-3303, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33864112

RESUMO

Methicillin-resistant Staphylococcus aureus is one of the major clinical problems in hospitals because of its resistance to many antimicrobials. Biocides are used in hospitals to control nosocomial infections. This work aimed to investigate the relationship between the presence of integrons and reduced susceptibility to both biocides and antimicrobials in nosocomial multidrug-resistant (MDR)-MRSA isolates. A total of 114 clinical and eight environmental MRSA isolates were collected from Zagazig University Hospitals and El-Ahrar Educational Hospital, Egypt. These isolates were identified as MRSA by disk diffusion method (DDM) and confirmed by PCR. Susceptibility profile against 12 antibiotics and five biocides was determined by DDM and agar dilution method, respectively. Presence of integrons was investigated by PCR in MDR isolates. Seventy-five clinical and six environmental isolates were MDR and had reduced susceptibility to biocides. Class I integron was detected in plasmid DNA of 34 isolates and genomic DNA of 14 isolates. Meanwhile, class II integron was only detected in plasmid DNA of 10 clinical isolates. This study revealed a high prevalence of MDR-MRSA clinical and environmental isolates, both had reduced susceptibility to investigated biocides. Class I integron was more predominant in plasmid DNA of isolates, indicating that plasmid is a major carrier for integrons that transfer resistance genes. In conclusion, the association between antibiotic resistance and biocides reduced susceptibility is alarming. The selection of curative antibiotic should depend on the antimicrobial susceptibility profile. Furthermore, biocides should always be used at appropriate concentrations to prevent the evolution of resistance and to control the hospital-transmission of MRSA.


Assuntos
Infecção Hospitalar/microbiologia , Desinfetantes/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Infecções Estafilocócicas/microbiologia , Antibacterianos/farmacologia , Egito , Hospitais , Humanos , Integrons , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação
15.
Angew Chem Int Ed Engl ; 60(24): 13513-13520, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-33829616

RESUMO

Carbon monoxide (CO) is an important gaseous signaling molecule. The use of CO-releasing molecules such as metal carbonyls enables the elucidation of the pleiotropic functions of CO. Although metal carbonyls show a broad-spectrum antimicrobial activity, it remains unclear whether the bactericidal property originates from the transition metals or the released CO. Here, we develop nonmetallic CO-releasing micelles via a photooxygenation mechanism of 3-hydroxyflavone derivatives, enabling CO release under red light irradiation (e.g., 650 nm). Unlike metal carbonyls that non-specifically internalize into both Gram-positive and Gram-negative bacteria, the nonmetallic micelles are selectively taken up by S. aureus instead of E. coli cells, exerting a selective bactericidal effect. Further, we demonstrate that the CO-releasing micelles can cure methicillin-resistant S. aureus (MRSA)-infected wounds, simultaneously eradicating MRSA pathogens and accelerating wound healing.


Assuntos
Antibacterianos/uso terapêutico , Monóxido de Carbono/metabolismo , Liberação Controlada de Fármacos/efeitos da radiação , Luz , Dermatopatias/tratamento farmacológico , Animais , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Monóxido de Carbono/química , Monóxido de Carbono/farmacologia , Monóxido de Carbono/uso terapêutico , Escherichia coli/efeitos dos fármacos , Flavanonas/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Camundongos , Micelas , Oxirredução , Fármacos Fotossensibilizantes/química , Dermatopatias/microbiologia , Dermatopatias/patologia , Espectrofotometria , Staphylococcus aureus/efeitos dos fármacos , Cicatrização/efeitos dos fármacos
16.
Artigo em Inglês | MEDLINE | ID: mdl-33852710

RESUMO

Despite the widespread use of chlorhexidine (CHX) to prevent infection, data regarding the in vitro action of CHX against methicillin-resistant Staphylococcus aureus (MRSA) are limited. Clinical isolates from Hospital das Clinicas, Sao Paulo, Brazil, identified during 2002/2003 and 2012/2013 were studied to describe the susceptibility to CHX and mupirocin, molecular characteristics, and virulence profile of MRSA. Susceptibility test to Mupirocin was performed by the disk diffusion method and to CHX by the agar dilution technique. PCR for virulence genes, mecA gene and Staphylococcal Cassette Chromosome mec (SCCmec) types were investigated as well. Mupirocin- and CHX-resistant isolates were sequenced using the IlluminaTM plataform. Two hundred and sixteen MRSA clinical isolates were evaluated: 154 from infected and 62 from colonized patients. Resistance to mupirocin was observed in four isolates assigned as SCCmec type III and STs (ST05; ST239 and ST105) carrying mupA and blaZ, two of them co-harboring the ileS gene. Only one isolate assigned as SCCmec type III was resistant to CHX (MIC of 8.0 µg.mL-1) and harbored the qacA gene. Resistance to chlorhexidine and mupirocin were found in isolates carrying qacA and mupA in our hospital. Since these genes are plasmid-mediated, this finding draws attention to the potential spread of resistance to mupirocin in our hospital.


Assuntos
Antibacterianos/farmacologia , Clorexidina/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Mupirocina/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas de Bactérias/genética , Brasil , Criança , Pré-Escolar , DNA Bacteriano/genética , Feminino , Hospitais de Ensino , Humanos , Lactente , Masculino , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Análise de Sequência de DNA , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Virulência , Adulto Jovem
17.
BMC Infect Dis ; 21(1): 372, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33882854

RESUMO

BACKGROUND: Some Staphylococcus aureus strains produce Panton-Valentine leukocidin (PVL), a bi-component pore-forming toxin, which causes leukocyte lysis and tissue necrosis. Currently, there is very limited information on the molecular epidemiology of PVL-encoding S. aureus strains in Iran. This study aimed to determine the molecular epidemiology and genetic background of PVL-positive S. aureus clinical strains isolated from Iranian patients. METHODS: A total of 28 PVL-positive S. aureus strains were detected from 600 S. aureus isolates between February 2015 and March 2018 from different hospitals in Tehran, Iran. Antimicrobial susceptibility testing was performed according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. Molecular genotyping was performed using SCCmec and accessory gene regulator (agr) typing, PVL haplotyping, multilocus sequence typing (MLST), and pulsed-field gel electrophoresis (PFGE). RESULTS: The highest antibiotic resistance rate was found to be against erythromycin (57.1%), followed by ciprofloxacin (42.8%) and clindamycin (35.7%). Moreover, 19 (67.9%) out of 28 S. aureus isolates were identified as MRSA, including CA-MRSA (14/19, 73.7%) and HA-MRSA (5/19, 26.3%). SCCmec type IVa was detected as the predominant type (10/19, 52.6%), followed by type III (5/19, 26.3%) and type V (4/19, 21.1%). The agr type I was identified as the most common type (14/28, 50%), and H and R haplotype groups were observed at frequencies of 67.9 and 32.1%, respectively. Among H variants, the predominant variant was H2 (78/9%). The isolates encompassed 21 different sequence types (STs), including 16 new STs (ST5147 to ST5162). Based on eBURST analysis, the isolates were clustered into five CCs, including CC30, CC22, CC1, CC8, and CC5 (ST5160), and nine singletons. PFGE typing showed that 24 isolates were clustered into A (4 pulsotypes), B (9 pulsotypes), and C (11 pulsotypes) clusters. CONCLUSIONS: A high prevalence of PVL-positive CA-MRSA strains was detected in Iran. The majority of PVL-positive isolates were of H (mostly H2) variant, while R variant was harbored by 100% of PVL-positive MRSA strains. Also, CC8, CC22, and CC30 were identified as the dominant clones among PVL-encoding S. aureus strains. This study promotes a better understanding of the molecular epidemiology and evolution of PVL-positive S. aureus strains in Iran.


Assuntos
Toxinas Bacterianas/genética , Exotoxinas/genética , Haplótipos , Leucocidinas/genética , Staphylococcus aureus Resistente à Meticilina/genética , Polimorfismo de Nucleotídeo Único , Infecções Estafilocócicas/epidemiologia , Antibacterianos/uso terapêutico , Toxinas Bacterianas/metabolismo , Farmacorresistência Bacteriana Múltipla/genética , Eletroforese em Gel de Campo Pulsado , Exotoxinas/metabolismo , Genômica , Humanos , Irã (Geográfico)/epidemiologia , Leucocidinas/metabolismo , Masculino , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/metabolismo , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Filogenia , Prevalência , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia
18.
Retina ; 41(8): 1709-1714, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33734193

RESUMO

PURPOSE: To describe endogenous endophthalmitis in the setting of COVID-19 pneumonia. METHODS: Patients recovering from COVID-19 pneumonia who presented to our department with any or all of the following complaints: pain, watering, redness, and decreased vision were identified. All relevant data were collected for analysis. RESULTS: Three patients with endogenous endophthalmitis were identified. All patients had been treated for COVID-19 pneumonia and therefore had received remdesivir and systemic steroids; 2 of the 3 patients received tocilizumab. All patients received vitreous biopsy, vitrectomy, and intraocular antibiotic injection. Patient 1 demonstrated Klebsiella pneumoniae in blood culture, K. pneumoniae and Escherichia coli in urine culture, and K. pneumoniae in vitreous fluid, whereas Patients 2 and 3 demonstrated Stenotrophomonas maltophilia and methicillin-resistant Staphylococcus aureus in the blood and nasopharyngeal culture, respectively. Correspondingly, the same organism was cultured from vitreous in Patients 2 and 3. The visual acuity at the last follow-up in Patients 1 to 3 was 20/100, 20/80, and 20/40, respectively. The probable source of infection was identified in each as renal calculi, dental caries, and the pharynx, respectively. Real-time polymerase chain reaction demonstrated the presence of Severe Acute Respiratory Syndrome Coronavirus 2 in the vitreous fluid of Patient 1. CONCLUSION: We report good outcomes of early intervention for endogenous endophthalmitis in the setting of COVID-19 infection. We also document the presence of SARS-CoV-2 in vitreous.


Assuntos
COVID-19/complicações , Endoftalmite/microbiologia , Infecções Oculares Bacterianas/microbiologia , Klebsiella pneumoniae/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , SARS-CoV-2/isolamento & purificação , Stenotrophomonas maltophilia/isolamento & purificação , Adulto , Idoso , Antibacterianos/uso terapêutico , Teste de Ácido Nucleico para COVID-19 , Endoftalmite/diagnóstico , Endoftalmite/tratamento farmacológico , Infecções Oculares Bacterianas/diagnóstico , Infecções Oculares Bacterianas/tratamento farmacológico , Feminino , Glucocorticoides/uso terapêutico , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Infecções por Klebsiella/diagnóstico , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/microbiologia , Masculino , Pessoa de Meia-Idade , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Vitrectomia , Corpo Vítreo/microbiologia , Corpo Vítreo/virologia
19.
JAMA Netw Open ; 4(3): e210971, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33720369

RESUMO

Importance: The effectiveness and importance of contact precautions for endemic pathogens has long been debated, and their use has broad implications for infection control of other pathogens. Objective: To estimate the association between contact precautions and transmission of methicillin-resistant Staphylococcus aureus (MRSA) across US Department of Veterans Affairs (VA) hospitals. Design, Setting, and Participants: This retrospective cohort study used mathematical models applied to data from a population-based sample of adults hospitalized in 108 VA acute care hospitals for at least 24 hours from January 1, 2008, to December 31, 2017. Data were analyzed from May 2, 2019, to December 11, 2020. Exposures: A positive MRSA test result, presumed to indicate contact precautions use according to the VA MRSA Prevention Initiative. Main Outcomes and Measures: The main outcome was the association between contact precautions and MRSA transmission, defined as the relative transmissibility attributed to contact precautions. A contact precaution effect estimate (<1 indicates a reduction in transmission associated with contact precautions) was estimated for each hospital and then pooled over time and across hospitals using meta-regression. Results: In this cohort study of 108 VA hospitals, more than 2 million unique individuals had over 5.6 million admissions, of which 14.1% were presumed to have contact precautions with more than 8.4 million MRSA surveillance tests. Pooled estimates found associations between contact precautions and transmission to be stable from 2008 to 2017, with estimated transmission reductions ranging from 43% (95% credible interval [CrI], 38%-48%) to 51% (95% CrI, 46%-55%). Over the entire 10-year study period, contact precautions reduced transmission 47% (95% CrI, 45%-49%), and the intrafacility autocorrelation coefficient estimate was 0.99, suggesting consistent estimates over time within facilities. Larger facilities and those with higher admission screening compliance observed additional reductions in transmission associated with contact precautions (relative rate, 0.84; 95% CI, 0.74-0.96 and 0.74; 95% CI, 0.58-0.96, respectively) compared with smaller facilities and those with lower admission screening compliance. Facilities in the southern US had a smaller transmission reduction attributable to contact precautions (relative rate, 1.14; 95% CI, 1.01-1.28) compared with facilities in other regions in the US. Conclusions and Relevance: In this cohort study of adults in VA hospitals, transmissibility of MRSA was found to be reduced by approximately 50% among patients with contact precautions. These results provide an explanation for decreasing acquisition rates in VA hospitals since the MRSA Prevention Initiative.


Assuntos
Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/transmissão , Controle de Infecções/métodos , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas/prevenção & controle , Infecções Estafilocócicas/transmissão , Estudos de Coortes , Hospitais de Veteranos , Humanos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Estudos Retrospectivos , Estados Unidos , United States Department of Veterans Affairs
20.
Int J Food Microbiol ; 346: 109165, 2021 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-33770679

RESUMO

Methicillin-resistant S. aureus (MRSA) and their antimicrobial resistance pose exacerbating global health threats and endangering everyone. Thus, the prevalence, molecular characterization of virulence genes, and antimicrobial resistance patterns of strains isolated from 225 beef burger and hot dog sandwiches vended in Mansoura city, Egypt were determined. 83.1% of the sandwiches tested were contaminated with coagulase-positive S. aureus, with a mean count of 4 × 103 CFU/g. Genes encoding mecA, α-hemolysin, staphylococcal enterotoxins, and toxic shock syndrome toxin-1 were detected in 22.6%, 96.3%, 61.1%, and 0% of the strains isolated, respectively. Of the 190 coagulase-positive strains, 43 (22.6%) were confirmed as MRSA. Among them, 4 strains (2.1%) were vancomycin-resistant S. aureus (VRSA) and resistant to all antimicrobials tested. Interestingly, all isolates were resistant to at least one of the antimicrobials tested, with 75.2% being multi-drug resistant (MDR) and an average multiple antimicrobial resistance (MAR) index of 0.503. Not less important, 100%, 96.3%, 90.5%, 79.5%, 73.7%, 62.6%, and 48.9% of isolates were resistant to Kanamycin, Nalidixic acid, Cefotaxime, Sulphamethoxazole-Trimethoprim, Penicillin G, Tetracycline, and Cephalothin, respectively. The potential hazard of MDR-, MRSA-, and VRSA-contaminated sandwiches may be an indication of the presence of what is more dangerous. Hence, strict hygienic measures and good standards of food handler's personal hygiene to prevent transmission of these pathogens to consumers are imperative.


Assuntos
Fast Foods/microbiologia , Contaminação de Alimentos/análise , Produtos da Carne/microbiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Vancomicina/isolamento & purificação , Animais , Antibacterianos/farmacologia , Bovinos , Qualidade de Produtos para o Consumidor , Farmacorresistência Bacteriana Múltipla , Egito , Enterotoxinas/genética , Contaminação de Alimentos/estatística & dados numéricos , Humanos , Produtos da Carne/análise , Meticilina/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Saúde Pública , Suínos , Vancomicina/farmacologia , Staphylococcus aureus Resistente à Vancomicina/efeitos dos fármacos , Staphylococcus aureus Resistente à Vancomicina/genética
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