Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 5.558
Filtrar
1.
Fortschr Neurol Psychiatr ; 87(9): 499-502, 2019 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-31519025

RESUMO

Strains of methicillin-resistant Staphylococcus aureus (MRSA) are of major economic and health-related importance to early neurological and neurosurgical rehabilitation. It is crucial to identify MRSA-carriers as soon as possible upon admission in order to prevent transmissions and to initiate contact precautions and decolonization. The present study focuses on validity of a polymerase chain reaction (PCR) test to identify MRSA genetic material from nasopharyngeal samples (BD MAX MRSA XT, BD Diagnostics, Heidelberg, Germany) of early neurological and neurosurgical rehabilitation patients. PCR-results were compared to gold standard (culture). In 2013, 66 patients were tested using PCR and incubation within one week after admission. Sensitivity of PCR was 84.6 %, specificity 86.6 %. Positive predictive value (PPV) was only 61.1 %, while negative predictive value was as high as 95.8 %. In 39 cases, PCR and subsequent culture were done within one day, leading to a sensitivity of 100 % and a specificity of 90.3 %. In this subgroup, PPV was 72.7 %, NPV 100 %. The results from the study suggest that incubation should quickly follow a positive PCR finding (within 24 hours) in order to verify MRSA colonization. High NPV (95.8 resp. 100 %) indicate that PCR negative patients very likely are not colonized with MRSA. A positive PCR test is less reliable (due to false positive results) and should be followed by incubation in due course in order to avoid unnecessary contact precautions.


Assuntos
Programas de Rastreamento/normas , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Reabilitação Neurológica , Reação em Cadeia da Polimerase/normas , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/microbiologia , Alemanha , Humanos , Sensibilidade e Especificidade
2.
J Med Microbiol ; 68(9): 1367-1372, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31329093

RESUMO

Methicillin-resistant Staphylococcus lugdunensis (MRSL) is increasingly recognized in healthcare and community settings. To obtain a better understanding of the emergence of MRSL, this study characterized the structure and content of the SCCmec elements harboured by 36 MRSL isolates obtained from diverse sources in Hong Kong from 2008 to 2017. The isolates were investigated by whole-genome sequencing. SCCmec types and subtypes were assigned according to the guidelines from the International Working Group on the Classification of Staphylococcal Cassette Chromosome Elements. The sequence type (ST)-SCCmec combinations in the 36 MRSL isolates were as follows: ST3-SCCmec IV (n=2), ST3-SCCmec V (n=28), ST27-SCCmec V (n=5) and ST42-SCCmec V (n=1). The two SCCmec IV elements were highly similar to the SCCmec IV element harboured by the community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) strain, JCSC6668. The J3-mec complex-J2 regions in the SCCmec V elements were highly similar to the corresponding regions in the CA-MRSA strains PM1 (n=13) or WIS (n=21). Based on the J1 to J3 sequences, the SCCmec V elements can be categorized into nine different subtypes. Our findings highlight the diversified structures of SCCmec elements among MRSL strains and their close relationship with SCCmec elements harboured by CA-MRSA.


Assuntos
Cromossomos Bacterianos/genética , Infecções Comunitárias Adquiridas/microbiologia , Genes Bacterianos/genética , Staphylococcus aureus Resistente à Meticilina/genética , Infecções Estafilocócicas/microbiologia , Staphylococcus lugdunensis/genética , Antibacterianos/farmacologia , Infecções Comunitárias Adquiridas/epidemiologia , DNA Bacteriano/genética , Genoma Bacteriano/genética , Hong Kong/epidemiologia , Humanos , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Análise de Sequência de DNA , Infecções Estafilocócicas/epidemiologia , Estudantes de Medicina
3.
BMC Infect Dis ; 19(1): 596, 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31288757

RESUMO

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is associated with significant morbidity and mortality and has resultant important economic and societal costs underscoring the need for accurate surveillance. In recent years, prevalence rates reported in East Africa have been inconsistent, sparking controversy and raising concern. METHODS: We described antimicrobial susceptibility patterns of Staphylococcus aureus isolates cultured from patients within the Internal Medicine department of the largest public healthcare facility in East and Central Africa- the Kenyatta National Hospital (KNH) in Nairobi, Kenya. Routine antimicrobial susceptibility data from non-duplicate Staphylococcus aureus isolates cultured between the years 2014-2016 from the medical wards in KNH were reviewed. RESULTS: Antimicrobial susceptibility data from a total of 187 Staphylococcus aureus isolates revealed an overall MRSA prevalence of 53.4%. Isolates remained highly susceptible to linezolid, tigecycline, teicoplanin and vancomycin. CONCLUSIONS: The prevalence of MRSA was found to be much higher than that reported in private tertiary facilities in the same region. Careful interrogation of antimicrobial susceptibility results is important to uproot any red herrings and reserve genuine cause for alarm, as this has a critical bearing on health and economic outcomes for a population.


Assuntos
Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas/diagnóstico , Adulto , África Oriental/epidemiologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Cefoxitina/farmacologia , Cefoxitina/uso terapêutico , Feminino , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Prevalência , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação
4.
Medicine (Baltimore) ; 98(27): e16015, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31277095

RESUMO

The aim of this study was to describe the clinical features of bone and joint infections (BJI) due to Panton-Valentine Leukocidin producing (PVL+) Staphylococcus aureus (SA) in French Guiana.A multicenter study that consists of a retrospective charts review of children admitted for PVL+ S. aureus BJI between January 2010 and December 2015.Six patients with SA-PVL BJI were identified during the study period: 2 osteomyelitis, 1 septic arthritis, and 3 disseminated BJI. The median age was 11 years old (4-14 years), and fever lasted for 3.2 days (2-5 days) before diagnosis. An open skin wound preceded the BJI in 5/6 patients. One patient presented with a septic thrombophlebitis of the femoral-popliteal vein on admission. Methicillin-susceptible Staphylococcus aureus (MSSA) were identified for all patients. Three patients had complications: 2 cases of necrotizing pneumonia and 2 pericarditis, with 1 death caused by cardiac tamponade.SA-PVL BJI was not frequent. Strains were susceptible to methicillin, but responsible of severe BJI. Early diagnosis and a multidisciplinary management of these infections are essential to prevent further complications.


Assuntos
Artrite Infecciosa/microbiologia , Toxinas Bacterianas/análise , Exotoxinas/análise , Leucocidinas/análise , Osteomielite/microbiologia , Infecções Estafilocócicas/microbiologia , Adolescente , Antibacterianos/uso terapêutico , Artrite Infecciosa/terapia , Proteína C-Reativa/análise , Criança , Pré-Escolar , Guiana Francesa , Humanos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Osteomielite/terapia , Estudos Retrospectivos , Infecções Estafilocócicas/terapia
5.
Vet Microbiol ; 235: 118-126, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31282369

RESUMO

The aim of the present study was to investigate the diversity of methicillin-resistant Staphylococcus aureus (MRSA) that originated from Austrian companion animals during the last five-year period. A total of 90 non-repetitive MRSA isolates were obtained during diagnostic activities from autumn 2013 to autumn 2018. They originated from horses (n = 62), cats (n = 13), dogs (n = 10), rabbits (n = 2), a domestic canary, a zoo-kept hammer-headed bat (Hypsignathus monstrosus) and a semi-captive northern bald ibis (Geronticus eremita). Antimicrobial susceptibility testing was performed. All isolates were mecA-positive and mecC-negative. The isolates were genotyped by SCCmec, spa and dru typing, Multiple-Locus Variable number of tandem repeat Analyses (MLVA), S. aureus DNA microarray, and whole-genome sequencing (WGS). Eight sequence types (STs - ST398, ST5275 (new ST), ST225, ST8, ST22, ST152, ST1, and ST45), three SCCmec types (II, IV, and V), sixteen spa types (t003, t008, t011, t015, t032, t034, t1381, t1928, t1985, t223, t334, t355, t430, t6447, t6867, and t7105), fourteen dru types (dt10a, dt10az, dt10q, dt10r, dt11a, dt5e, dt6j, dt9a, dt9ak, dt9g, and four new types dt8as, dt7ak, dt4j, dt14n), and thirty-five MLVA types were detected. WGS-based core genome MLST (cgMLST) displayed five main clusters. Compared to the time period 2004-2013, the results of the present study show not only a higher diversity among the MRSA isolates within the population of Austrian companion animals, but also the introduction of new clones. Although ST398 isolates remained predominant, mainly due to high presence of this lineage among horses, increasing isolation rates of human-associated MRSA clones were observed in cats and dogs.


Assuntos
Variação Genética , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/genética , Animais de Estimação/microbiologia , Infecções Estafilocócicas/veterinária , Animais , Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana , Gatos/microbiologia , Cães/microbiologia , Genótipo , Humanos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Análise de Sequência com Séries de Oligonucleotídeos , Sequenciamento Completo do Genoma
6.
Vet Microbiol ; 233: 5-10, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31176412

RESUMO

This work aimed to determine the prevalence, diversity, antibiotic-resistance phenotype/genotype and virulence factors in staphylococci of farm-animals. Nasal samples of 117 farm-animals (calve: 72; lamb: 37; goat: 8) were collected from one slaughterhouse in La Rioja/Spain and cultured for staphylococci and methicillin-resistant Staphylococcus (MRS) recovery. Identification was performed by MALDI-TOF. Antimicrobial resistance phenotype/genotype was determined by susceptibility testing and specific PCRs. Molecular typing (spa-typing, multilocus-sequence-typing, agr-typing, SCCmec), and detection of 12 virulence genes and human Immune-evasive-cluster (IEC) genes were performed by PCR/sequencing in S. aureus. Two marker genes of arginine catabolic mobile element (ACME) were determined by PCR (USA300-MRSA detection). Staphylococci were identified in 50%, 54% and 21% of goat, lamb and calve samples, respectively. Among the 13 S. aureus isolates recovered, 11 were susceptible to all antimicrobials tested, and two were multidrug-resistant-MRSA [beta-lactams (blaZ, mecA), macrolides [(msr(A)/msr(B)] and fluoroquinolones]. The MSSA harboured either tst or enterotoxin genes, while the MRSA harboured the lukF/lukS-PV genes. Five sequence-types were detected. The two MRSA strains (from lamb and goat) were typed as t5173/ST8/agr-I/SCCmec-IVa/ACME-positive, corresponding to USA300 clone, and were IEC-B-positive. Among the 47 coagulase-negative staphylococci (CoNS), six species were identified, predominating S. simulans (n = 25) and S. sciuri (n = 11). Fifty-three percent of CoNS showed resistance to at least one antimicrobial agent (six multidrug-resistant strains), and the following resistance phenotypes/genotypes were detected: streptomycin [27.6%; ant(6)-Ia, str], tetracycline [23.4%; tet(M), tet(L), tet(K)], clindamycin [19.1%; lnu(A), vgaA], erythromycin [10.6%; erm(C), msr(A)/msr(B)], chloramphenicol (8.5%; fexA), tobramycin (6.4%), penicillin-cefoxitin (4.3%; blaZ, mecA), and SXT (2.1%). The detection of the MRSA-USA300 lineage in food animals is worrisome and should be further monitored.


Assuntos
Portador Sadio/veterinária , Reservatórios de Doenças/veterinária , Variação Genética , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus/classificação , Fatores de Virulência/genética , Animais , Antibacterianos/farmacologia , Portador Sadio/microbiologia , Reservatórios de Doenças/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Genes Bacterianos , Genótipo , Cabras/microbiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Nariz/microbiologia , Reação em Cadeia da Polimerase , Prevalência , Carne Vermelha/microbiologia , Ovinos/microbiologia , Espanha/epidemiologia , Infecções Estafilocócicas/epidemiologia , Staphylococcus/efeitos dos fármacos , Tetraciclina/farmacologia
7.
Pan Afr Med J ; 32: 103, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31223393

RESUMO

Introduction: Staphylococcus aureus is an important pathogen responsible for hospital and community acquired infection(s). Emerging resistance to methicillin in this organism has left physicians with few therapeutic alternatives to treat infections caused by it. This study was aimed at determining the antibiotic susceptibility patterns of Staphylococcus aureus strains isolated at the Yaounde Central Hospital, Cameroon. Methods: from January 2014 to November 2016, a total of 250 non repeated strains were isolated from various clinical specimens. Isolates and antibiotic susceptibility profiles were identified through standard microbiological techniques. Results: methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA) accounted respectively for 80% (201/205) and 20% (49/205) of the total strains isolated. MRSA strains displayed high resistance to cefoxitin (100%), cotrimoxazole (89%), vancomycin (79.7%), lincomycin (70.3%), tobramycin (72.5%), doxycycline (68.0%), kanamycin (69.7%) and erythromycin (55.7%). In contrast, a high susceptibility was observed with rifampicin (82.6%). KTG (42.3%) and constitutive MLSB (17.4%) were the most frequent phenotypes recorded. Conclusion: our results show that the carriage of acquired MRSA infections predominates in this population. Despite the noticeable multiresistance of MRSA strains to antibiotics, rifampicin remains the drugs of choice for the therapy of acquired MRSA infections in this setting. In order to slow down antimicrobial resistance, surveillance studies for antimicrobial susceptibility remains essential to identify resistance and inform policy on resistance.


Assuntos
Antibacterianos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Camarões/epidemiologia , Estudos Transversais , Farmacorresistência Bacteriana Múltipla , Feminino , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Estudos Prospectivos , Estudos Retrospectivos , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/isolamento & purificação
8.
J Med Microbiol ; 68(8): 1129-1136, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31241446

RESUMO

PURPOSE: Staphylococcus aureus causes a wide range of infections, such as endocarditis, pneumonia, osteomyelitis, skin and soft tissue infections, and implant/in-dwelling device-related infections. S. aureus poses a significant challenge to clinicians because of its ability to rapidly acquire multi-drug resistance and quickly progress into a recurrent, chronic infection by biofilm formation. Levonadifloxacin (WCK 771) is a novel broad-spectrum antibacterial agent (it recently completed a phase 3 trial in India) with a differentiated mechanism of action involving high affinity to staphylococcal DNA gyrase, and is active against multi-drug-resistant (MDR) S. aureus, including those that are resistant to quinolones. The present study investigated the bactericidal activity of levonadifloxacin against biofilm-embedded S. aureus clinical isolates in comparison with other anti-S. aureus drugs. METHODOLOGY: The bactericidal activity of levonadifloxacin and comparator drugs such as vancomycin, linezolid and daptomycin was evaluated against planktonic and biofilm-encapsulated recent methicillin- and quinolone-resistant S. aureus clinical isolates using time-kill, biofilm eradication and scanning electron microscopy analysis. RESULTS: Levonadifloxacin displayed a consistent ≥90 % bacterial kill rate against biofilm-embedded organisms, while vancomycin and linezolid displayed variable activity and daptomycin did not show any activity. Scanning electron microscopy images further confirmed the efficacy of levonadifloxacin against biofilm, showing the disruption of biofilm structure and a corresponding reduction in the viable bacterial count. CONCLUSION: These results show that levonadifloxacin has an improved bactericidal effect on biofilm-embedded quinolone-resistant S. aureus and meticillin-resistant S. aureus, and that it can be a promising treatment option for such infections.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Fluoroquinolonas/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Humanos , Meticilina/farmacologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/fisiologia , Staphylococcus aureus Resistente à Meticilina/ultraestrutura , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Quinolonas/farmacologia , Infecções Estafilocócicas/microbiologia , Fatores de Tempo
9.
Int J Food Microbiol ; 304: 119-126, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31195259

RESUMO

Staphylococcus aureus encodes numerous toxins that are known or strongly suspected to cause specific diseases or symptoms. Panton-Valentine leukocidin (PVL) is one of these important toxins that is associated with high mortality rates. In our previous study, 1581 S. aureus strains were isolated from 4300 samples of retail foods obtained from most of the provincial capitals in China from 2011 to 2016. This study aimed to investigate the prevalence of PVL-positive S. aureus isolates from retail foods in China and characterize these isolates by antibiotic resistance testing, spa typing, multilocus sequence typing (MLST) and enterotoxin gene analyses. In total, seventy-two isolates (72/1581, 4.6%) possessed pvl genes, including 24.1% MRSA isolates (26/108) and 3.1% MSSA isolates (46/1473), covering different types of food. The strains were divided into seventeen sequence types (STs) and twenty-seven spa types, and 43.1% (31/72) of the PVL-positive S. aureus isolates belonged to CC59-t437. These isolates contained at least one of the following enterotoxin genes: sei (97.2%), sem (86.1%), seq (80.6%), seg (68.1%), sek (68.1%), seb (62.5%), sel (52.8%), sej (50.0%), seh (48.6%), sep (45.8%), sea (38.9%), ser (37.5%), sen (27.8%), sec (16.7%), see (16.7%), sed (6.9%), seo (6.9%) and seu (6.7%). A total of 87.5% of the S. aureus isolates (63/72) harboured the classic SE genes (sea, seb, sec, sed, and see), whereas all the S. aureus isolates harboured the genes of the egc cluster (seg, sei, sem, sen, seo, and seu). In antimicrobial susceptibility tests, 98.6% of the isolates (71/72) exhibited resistance to at least one antibiotic, including 47 multi-drug-resistant isolates. Resistance to penicillin (94.4%), erythromycin (83.4%), clindamycin (63.9%), kanamycin (61.1%), telithromycin (58.3%), streptomycin (51.4%), tetracycline (47.2%), chloramphenicol (27.8%), fusidic acid (27.8%) and other antibiotics (<20%) was observed. All the PVL-positive MRSA isolates belonged to CC59-t437, which is the predominant type of community-associated (CA)-MRSA in China. The presence of these isolates in food represents a potential health risk for consumers and warrants further attention.


Assuntos
Toxinas Bacterianas/genética , Farmacorresistência Bacteriana Múltipla/genética , Enterotoxinas/genética , Exotoxinas/genética , Leucocidinas/genética , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Infecções Estafilocócicas/epidemiologia , Antibacterianos/farmacologia , China/epidemiologia , Contaminação de Alimentos/análise , Microbiologia de Alimentos/métodos , Doenças Transmitidas por Alimentos/microbiologia , Genótipo , Humanos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Tipagem de Sequências Multilocus , Prevalência , Infecções Estafilocócicas/microbiologia
10.
Pol J Microbiol ; 68(1): 59-69, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31050254

RESUMO

The widespread of infections caused by methicillin-resistant Staphylococcus aureus (MRSA), has necessitated the search for alternative therapies; introduction of new agents being a suggestion. This study compares the in vitro and in vivo activities of zabofloxacin, a novel fluoroquinolone, with moxifloxacin, levofloxacin and ciprofloxacin against clinical isolates of MRSA from patients hospitalized in the Alexandria Main University hospital; a tertiary hospital in Alexandria, Egypt, where zabofloxacin has not been yet introduced. The strains tested showed the highest percentage of susceptibility to zabofloxacin (61.2%) among the tested fluoroquinolones with the most effective MIC50 and MIC90 (0.25 and 2 µg/ml, respectively). Time-kill curve analysis revealed a rapid bactericidal activity of zabofloxacin after 6 h of incubation with a quinolone-resistant isolate and complete killing when tested against a quinolone-sensitive isolate with inhibition of regrowth in both cases. PCR amplification and sequencing of QRDRs in selected strains revealed the following amino acid substitutions: Ser-84→Leu in GyrA, Ser-80→Phe in GrlA and Pro-451→Ser in GrlB. The in vivo studies demonstrated that zabofloxacin possessed the most potent protective effect against systemic infection in mice (ED50: 29.05 mg/kg) with lowest count in the dissected lungs (3.66 log10 CFU/ml). The histopathological examination of lung specimens of mice treated with zabofloxacin displayed least congestion, inflammation, oedema and necrosis with clear alveolar spaces and normal vessels. In conclusion, zabofloxacin was proved to possess high in vitro and in vivo efficacy encompassing its comparators and could be considered as a possible candidate for the treatment of infections caused by MRSA. To our knowledge, this is the first study evaluating the in vitro and in vivo activity of zabofloxacin against Egyptian MRSA clinical isolates.The widespread of infections caused by methicillin-resistant Staphylococcus aureus (MRSA), has necessitated the search for alternative therapies; introduction of new agents being a suggestion. This study compares the in vitro and in vivo activities of zabofloxacin, a novel fluoroquinolone, with moxifloxacin, levofloxacin and ciprofloxacin against clinical isolates of MRSA from patients hospitalized in the Alexandria Main University hospital; a tertiary hospital in Alexandria, Egypt, where zabofloxacin has not been yet introduced. The strains tested showed the highest percentage of susceptibility to zabofloxacin (61.2%) among the tested fluoroquinolones with the most effective MIC50 and MIC90 (0.25 and 2 µg/ml, respectively). Time-kill curve analysis revealed a rapid bactericidal activity of zabofloxacin after 6 h of incubation with a quinolone-resistant isolate and complete killing when tested against a quinolone-sensitive isolate with inhibition of regrowth in both cases. PCR amplification and sequencing of QRDRs in selected strains revealed the following amino acid substitutions: Ser-84→Leu in GyrA, Ser-80→Phe in GrlA and Pro-451→Ser in GrlB. The in vivo studies demonstrated that zabofloxacin possessed the most potent protective effect against systemic infection in mice (ED50: 29.05 mg/kg) with lowest count in the dissected lungs (3.66 log10 CFU/ml). The histopathological examination of lung specimens of mice treated with zabofloxacin displayed least congestion, inflammation, oedema and necrosis with clear alveolar spaces and normal vessels. In conclusion, zabofloxacin was proved to possess high in vitro and in vivo efficacy encompassing its comparators and could be considered as a possible candidate for the treatment of infections caused by MRSA. To our knowledge, this is the first study evaluating the in vitro and in vivo activity of zabofloxacin against Egyptian MRSA clinical isolates.


Assuntos
Antibacterianos/farmacologia , Fluoroquinolonas/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Animais , Carga Bacteriana/efeitos dos fármacos , Ciprofloxacino/farmacologia , DNA Girase/efeitos dos fármacos , DNA Girase/genética , DNA Topoisomerase IV/efeitos dos fármacos , DNA Topoisomerase IV/genética , Egito , Hospitais Universitários , Humanos , Levofloxacino/farmacologia , Pulmão/microbiologia , Pulmão/patologia , Masculino , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Camundongos , Testes de Sensibilidade Microbiana , Moxifloxacina/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia
11.
Pol J Microbiol ; 68(1): 93-104, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31050257

RESUMO

Staphylococcus aureus is a common human and livestock opportunistic pathogen, and there is evidence of animal to human transmission. This paper aimed to recognize properties of the isolates from collections of human and livestock S. aureus strains and to estimate compatibility of results based on phenotypic tests, microarrays and the spa typing methods. The second goal was to study differences between human and animal isolates in terms of specificity of their hosts and the strain transmission among various hosts. Most strains showed multi-susceptible profiles and produced enzymes on a high level, and they were phenotypically and genetically similar. However, in contrast to the Polish bovine mastitis strains, the Slovakian strains were multi-resistant. In this research, the strains showed significant differences in terms of their phenotypic manifestations and the presence of hemolysins genes; however, other enzyme-encoding genes correlated to a higher extent with the microarrays results. Interestingly, there was a lack of enterotoxin genes in human Poultry-like protein A+ strains in comparison to other human strains. Our study showed that differences between virulence profiles of the human and animal strains correlated with their origin rather than their hosts, and any trait allowed clearly distinguishing between them based on the microarray results.Staphylococcus aureus is a common human and livestock opportunistic pathogen, and there is evidence of animal to human transmission. This paper aimed to recognize properties of the isolates from collections of human and livestock S. aureus strains and to estimate compatibility of results based on phenotypic tests, microarrays and the spa typing methods. The second goal was to study differences between human and animal isolates in terms of specificity of their hosts and the strain transmission among various hosts. Most strains showed multi-susceptible profiles and produced enzymes on a high level, and they were phenotypically and genetically similar. However, in contrast to the Polish bovine mastitis strains, the Slovakian strains were multi-resistant. In this research, the strains showed significant differences in terms of their phenotypic manifestations and the presence of hemolysins genes; however, other enzyme-encoding genes correlated to a higher extent with the microarrays results. Interestingly, there was a lack of enterotoxin genes in human Poultry-like protein A+ strains in comparison to other human strains. Our study showed that differences between virulence profiles of the human and animal strains correlated with their origin rather than their hosts, and any trait allowed clearly distinguishing between them based on the microarray results.


Assuntos
Reservatórios de Doenças/microbiologia , Mastite Bovina/microbiologia , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas/microbiologia , Animais , Antibacterianos/farmacologia , Bovinos , Farmacorresistência Bacteriana Múltipla/genética , Proteínas Hemolisinas/genética , Humanos , Gado/microbiologia , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Infecções Oportunistas/microbiologia
12.
J Med Microbiol ; 68(9): 1299-1305, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31140965

RESUMO

The spread of multidrug-resistant Staphylococcus aureus is a public health concern. The inducible macrolide-lincosamide-streptogrammin B (iMLSB ) phenotype (or inducible clindamycin resistance) is associated with false clindamycin susceptibility in routine laboratory testing and may lead to treatment failure. Tigecycline resistance remains rare in S. aureus worldwide. This study aims to determine the antimicrobial susceptibility profiles of clinical isolates of S. aureus obtained from the main tertiary hospital in Terengganu state, Malaysia, from July 2016 to June 2017. The antimicrobial susceptibilities of 90 methicillin-resistant S. aureus (MRSA) and 109 methicillin-susceptible S. aureus (MSSA) isolates were determined by disc diffusion with the iMLSB phenotype determined by D-test. Multidrug resistance (MDR) and the iMLSB phenotype were more prevalent in MRSA (84.4 and 46.7  %, respectively) compared to MSSA isolates. All five tigecycline-resistant isolates were MRSA. The high incidence of MDR and the iMLSB phenotype and the emergence of tigecycline resistance in the Terengganu S. aureus isolates warrants continuous vigilance.


Assuntos
Antibacterianos/farmacologia , Clindamicina/farmacologia , Farmacorresistência Bacteriana Múltipla , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Infecções Estafilocócicas/microbiologia , Tigeciclina/farmacologia , Feminino , Humanos , Malásia/epidemiologia , Masculino , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Fenótipo , Prevalência , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Centros de Atenção Terciária
13.
Harefuah ; 158(5): 288-293, 2019 May.
Artigo em Hebraico | MEDLINE | ID: mdl-31104387

RESUMO

INTRODUCTION: Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of morbidity. Data regarding MRSA infections in children in Israel are scarce. OBJECTIVES: We assessed MRSA prevalence, risk factors and clinical manifestations in children with Staphylococcus aureus infections in southern Israel. METHODS: Our medical center is the sole hospital in southern Israel. All medical files of Staphylococcus aureus infections during the period 2005-2015, were reviewed retrospectively. RESULTS: Overall, 1,062 SA infections (MRSA; n=164, 15%) were identified; 687 (65%) skin and soft tissue infections (SSTI), and 375 (35%) invasive infections. MRSA was significantly more common in children <5 years (18% vs. 13% in children ≥5 years), Bedouin ethnicity (19% vs. 8% in Jewish children), burns (24% vs. 15%), congenital insensitivity to pain with anhidrosis (CIPA; 90% vs. 15%) and SSTI (17% vs. 12% in invasive infections). Blood count parameters and hospital-associated vs. community-acquired infection rates were similar comparing MRSA and Methicillin-susceptible Staphylococcus aureus (MSSA). In multivariate analysis, age (odds ratio, OR=0.953), Bedouin ethnicity (OR=2.698), burns (OR=2.036) and SSTI (OR=1.674) were associated with MRSA. MRSA isolates were more frequently resistant than MSSA to clindamycin (30% vs. 14%), erythromycin (34% vs. 15%), co-trimoxazole, tetracycline, rifampicin, ciprofloxacin and gentamicin (4% vs. 0.5%, all). All isolates were vancomycin susceptible. CONCLUSIONS: MRSA infections are common in young, Bedouin children and burns, and are more commonly multidrug resistant than MSSA in our region. Our data should be used to better identify and treat children with MRSA infection.


Assuntos
Infecções Comunitárias Adquiridas , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Antibacterianos , Criança , Humanos , Israel/epidemiologia , Meticilina , Resistência a Meticilina , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Estudos Retrospectivos , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus
14.
BMC Res Notes ; 12(1): 244, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-31036061

RESUMO

OBJECTIVES: Diabetic foot ulcers (DFUs) often lead to hospital admissions, amputations and deaths; however, there is no up-to-date information on microbial isolates from DFUs and no mention of utilization of molecular techniques in Sub-Saharan Africa. We conducted a cross-sectional study among 83 adult patients at a tertiary hospital in Kenya over 12 months. The study aimed to isolate, identify bacteria, their antibiotic susceptibility patterns in active DFUs, and to compare standard microbiological methods versus a real-time PCR commercial kit in the detection of Staphylococcus aureus DNA and methicillin-resistant S. aureus (MRSA) DNA. RESULTS: Eighty swabs (94%) were culture-positive; 29% were Gram-positive and 65% were Gram-negative. The main organisms isolated were S. aureus (16%), Escherichia coli (15%), Proteus mirabilis (11%), Klebsiella pneumoniae (7%) and Pseudomonas aeruginosa (7%). The bacterial isolates showed resistance to commonly used antibiotics such as ampicillin, amoxicillin, cefepime, ceftazidime, cefuroxime, clindamycin, erythromycin, piperacillin-tazobactam, tetracycline and trimethoprim-sulphamethoxazole (TMPSMX). Thirty-one percent of the S. aureus isolated and 40% of the Gram-negatives were multi-drug resistant organisms (MDROs). There was a high prevalence of nosocomial bacteria. MRSA were not identified using culture methods but were identified using PCR. PCR was more sensitive but less specific than culture-based methods to identify S. aureus.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/diagnóstico , Pé Diabético/diagnóstico , Farmacorresistência Bacteriana Múltipla , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Técnicas de Tipagem Bacteriana , Cefalosporinas/uso terapêutico , Clindamicina/uso terapêutico , Estudos Transversais , Pé Diabético/tratamento farmacológico , Pé Diabético/epidemiologia , Pé Diabético/microbiologia , Escherichia coli/classificação , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Humanos , Quênia/epidemiologia , Klebsiella pneumoniae/classificação , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Macrolídeos/uso terapêutico , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Penicilinas/uso terapêutico , Proteus mirabilis/classificação , Proteus mirabilis/efeitos dos fármacos , Proteus mirabilis/genética , Proteus mirabilis/isolamento & purificação , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Staphylococcus aureus/classificação , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Sulfanilamidas/uso terapêutico
15.
Braz J Infect Dis ; 23(2): 134-138, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31103436

RESUMO

This study characterized 30 MRSA isolates from intensive care unit (ICU) environment and equipment surfaces and healthy children. The SCCmec types I, IVa and V were detected in HA-MRSA isolates while CA-MRSA showed the SCCmec type IVa and V. Most isolates were classified as agr group II. All isolates presented the sei gene, and only HA-MRSA were positive for etb e tst genes. Three genotypes were related to Pediatric (ST5/SCCmecIV) and Berlin (ST45/SCCmecIV) clones. The present study showed molecular similarity between CA- and HA-MRSA isolates in hospital and community settings in a Brazilian region.


Assuntos
Infecções Comunitárias Adquiridas/microbiologia , Infecção Hospitalar/microbiologia , Unidades de Terapia Intensiva/estatística & dados numéricos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Brasil , Equipamentos e Provisões Hospitalares/microbiologia , Genótipo , Humanos , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/microbiologia , Fatores de Virulência/genética , Fatores de Virulência/isolamento & purificação
16.
Lett Appl Microbiol ; 69(1): 41-49, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31044446

RESUMO

Plumbagin (5-hydroxy-2-methyl-1,4-napthoquinone) is a bicyclic naphthoquinone, found in three major plant families viz. Plumbaginaceae, Ebenceae and Droseraceae. The phytochemical is reported to exhibit various pharmacological properties. In this study, plumbagin isolated from Plumbago zeylanica L. was investigated for its in vitro activity against methicillin-resistant Staphylococcus aureus (MRSA). Against 100 MRSA isolates that included multi-drug-resistant phenotypes, plumbagin showed consistent activity with a narrow minimum inhibitory concentration (MIC) range of 4-8 µg ml-1 . The time-kill study revealed 99% kill of a reference MRSA strain, 8 h after exposure to plumbagin. In the combination MIC study using the reference MRSA strain, plumbagin showed synergistic effect with ciprofloxacin and piperacillin while additive or indifference effect with other commonly used antibiotics. The transmission electron micrograph of the reference MRSA strain treated with plumbagin confirmed cell wall and cytoplasmic changes. Our results demonstrated potent anti-MRSA activity of plumbagin which was not impacted by multi-drug resistance. This is a first ever study that evaluated in vitro anti-MRSA activity of plumbagin employing large number of MRSA isolates. The findings of this study support the need for the further investigation on this phytochemical agent for therapeutic application. SIGNIFICANCE AND IMPACT OF THE STUDY: This study revealed phytochemical plumbagin's potent and consistent in vitro antibacterial activity against clinically problematic methicillin-resistant Staphylococcus aureus (MRSA) including multi-drug-resistant (MDR) phenotypes. The study results support further research to assess the clinical scope of plumbagin.


Assuntos
Antibacterianos/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Naftoquinonas/farmacologia , Extratos Vegetais/farmacologia , Plumbaginaceae/química , Parede Celular/efeitos dos fármacos , Ciprofloxacino/farmacologia , Citoplasma/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/farmacologia , Piperacilina/farmacologia
17.
Expert Opin Drug Saf ; 18(8): 635-650, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31106600

RESUMO

INTRODUCTION: Acute bacterial skin and skin-structure infections (ABSSSI) may develop in both in-patients and out-patients, possibly with a severe clinical presentation. Since most phase 3 randomized clinical trials have shown non-inferiority in efficacy across different agents, considerations regarding their different safety profiles inevitably play a crucial role in the everyday choice about which of them should be employed for the treatment of ABSSSI. AREAS COVERED: In this review, the authors discuss the safety profile of different treatment options for ABSSSI. EXPERT OPINION: The spread of methicillin-resistant Staphylococcus aureus (MRSA) in the last decades has inevitably influenced the therapeutic approach to ABSSSI. Adequate knowledge of the peculiar toxicity profile of each drug active against MRSA is essential for guiding, monitoring and managing adverse events, in turn reducing any unfavorable impact of toxicity on patients' outcomes. In the next five years, potential toxicity will play a critical role in establishing the best available therapy for each specific patient, together with consideration regarding the possibility of avoiding hospitalization or allowing a switch from intravenous to oral therapy and early discharge.


Assuntos
Antibacterianos/administração & dosagem , Dermatopatias Bacterianas/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico , Doença Aguda , Administração Intravenosa , Administração Oral , Antibacterianos/efeitos adversos , Monitoramento de Medicamentos/métodos , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Ensaios Clínicos Controlados Aleatórios como Assunto , Dermatopatias Bacterianas/microbiologia , Infecções Estafilocócicas/microbiologia
18.
BMC Infect Dis ; 19(1): 402, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31077140

RESUMO

BACKGROUND: There have been no reports regarding clinical features and molecular characteristics of childhood methicillin-susceptible Staphylococcus aureus (MSSA) infections in Taiwan. METHODS: We prospectively collected clinical S. aureus isolates from patients aged < 18 years in a university-affiliated hospital in 2015. Only the first isolate from each patient was included. Medical records were retrospectively reviewed. Patients were classified as community-associated (CA) or healthcare-associated (HA) by the epidemiologic criteria. All MSSA isolates were molecularly characterized. RESULTS: A total of 495 S. aureus isolates were identified, and 178 (36.0%) were MSSA. Among the 131 MSSA-infected patients enrolled, 94 (71.8%) were community-associated and 60 (45.8%) were inpatients. Patients with HA infections was significantly younger than those with CA infections (median, 15 vs. 67.5 months). The most common specimen of MSSA identified was pus or wound (73.3%). Compared to HA-MSSA, CA-MSSA isolates were significantly less frequently from sputum (6.4% vs. 27%, p = 0.001). Nineteen pulsotypes were identified. Four pulsotypes accounted for 60% of the isolates. Isolates of ST15/pulsotype F were more frequently seen in CA than in HA (p = 0.064) while isolates of ST188/pulsotype AX frequently seen in HA (p = 0.049). PVL genes were identified in 11 isolates (8.4%), nine of which were characterized as ST59/pulsotype D, same as the local endemic CA-MRSA clone. CONCLUSIONS: MSSA accounted for around one-third of childhood S. aureus infections in northern Taiwan. SSTI was the most common manifestation. The molecular characteristics of these clinical MSSA isolates were relatively diverse and had certain significant differences between CA and HA isolates.


Assuntos
Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas/microbiologia , Adolescente , Criança , Pré-Escolar , Infecções Comunitárias Adquiridas/microbiologia , Infecção Hospitalar/microbiologia , Feminino , Hospitais Universitários , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/genética , Estudos Prospectivos , Estudos Retrospectivos , Infecções Estafilocócicas/epidemiologia , Taiwan/epidemiologia
19.
J Appl Microbiol ; 127(1): 284-291, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31063623

RESUMO

AIMS: To determine the Staphylococcus aureus carriage rate in wild mammals in Aragon, northern Spain, to analyse their antimicrobial resistance phenotype/genotype and to characterize the recovered isolates. METHODS AND RESULTS: Nasal and rectal swabs of 103 mammals were collected in Aragón during the period 2012-2015. Antimicrobial susceptibility, the presence of antimicrobial resistance genes and virulence factors were investigated. Molecular characterization was carried out by spa, MLST, agr and SCCmec. Staphylococcus aureus were recovered from 23 animals (22%). Four of the 23 S. aureus were methicillin-resistant S. aureus (MRSA). Three MRSA were mecC-positive and were isolated from European rabbits and were typed as t843 (ascribed to CC130). The remaining MRSA was a mecA-carrying isolate from European hedgehog, typed as ST1-t386-SCCmecIVa-agrIII and it harboured the blaZ, erm(C), ant(6)-Ia and aph(3´)-IIIa resistance genes. A high diversity of spa-types was detected among the 19 methicillin-susceptible S. aureus isolates, which showed high susceptibility to the antimicrobials tested. The tst gene and different combinations of staphylococcal enterotoxins were found. CONCLUSIONS: Staphylococcus aureus were detected in nasal and rectal samples of wild mammals. Wild rabbits could be a reservoir of mecC-MRSA. SIGNIFICANCE AND IMPACT OF THE STUDY: This work provides information on the presence and characteristics of S. aureus from mammals in a defined geographic region in Spain.


Assuntos
Variação Genética , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/genética , Animais , Animais Selvagens/microbiologia , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Mamíferos/microbiologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Coelhos/microbiologia , Espanha/epidemiologia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Fatores de Virulência/genética
20.
Microb Pathog ; 132: 178-187, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31063809

RESUMO

Purified glycosides, Isoquercetin and Cassinopin from Crotalaria candicans were selected for the synthesis of biogenic copper nanoparticles (CuNPs).The designed biogenic CuNPs was characterized and when evaluated against panel of gram negative and positive bacteria, the biogenic CuNPs were found to be more effective against methicillin resistant Staphylococcus aureus (MRSA). Antibacterial, anti-biofilm effects and time kill studies confirmed the ability of biogenic CuNPs to curtail MRSA. Scanning electron microscopy, Crystal violet staining and fluorescent live-dead imaging showed that treatment with sub lethal levels of glycoside capped CuNPs resulted in greater than 50% decline in biofilm formation by MRSA, which implies that anti-biofilm effect of biogenic CuNPs is not dependent on antibacterial effect. Alizarin red assay implied that prolonged treatment of biogenic CuNPs in presence of MRSA, releases Cu(II) ions and hence antibiofilm effect is primarily mediated by NP and is not due to released Cu(II) ion. The NPs caused altered membrane permeability and reduced surface hydrophobicity, thus accounting for its antibiofilm effect.


Assuntos
Biofilmes/efeitos dos fármacos , Cobre/química , Nanopartículas Metálicas/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Antibacterianos/farmacologia , Aderência Bacteriana , Interações Hidrofóbicas e Hidrofílicas , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Quercetina/análogos & derivados , Quercetina/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA