TESTE DE HODGE MODIFICADO EM ÁGAR CLED PARA TRIAGEM DE Proteus mirabilis PRODUTORES DE CARBAPENEMASE

Enterobacteriaceae produtoras de carbapenemase vêm sendo descritas em todo o mundo.  Uma detecção precisa de bactérias produtoras de carpabenemase é necessária pois esta classe de antibióticos é usada no tratamento de infecções severas. A nível laboratorial, o método fenotípico para a detecção de produtores de carbapenemase é o teste de Hodge modificado. Entretanto, algumas enterobactérias tem grande motilidade dificultando a leitura e interpretação dos resultados desta técnica. O objetivo deste estudo foi validar um meio para se obter resultados confiáveis em bactérias com grande motilidade, como é o caso de Proteus mirabilis. O meio ágar Müller-Hinton, preconizado pelo CLSI, foi comparado ao ágar CLED que demostrou ser um bom meio para análise da produção de carbapenemase em Proteus mirabilis suspeitos de produzirem esta enzima embora todos os isolados tenham sido negativos no teste

Of Animal and Men: The Importance of Animal Environment to Antimicrobial Resistance: A One Health Approach

The contribution of the animal environments to the worsening of the global antimicrobial resistance framework is related to the use of antimicrobials in subtherapeutic doses and, for long periods, establishing ideal conditions for the circulation of resistance genes, which can be transmitted to pathogens adapted to the human microbiota. The study of the animal environment as conducive to the acceleration of resistance evolution is an emerging and critical area for understanding the development and dissemination of resistance genes among the circulating bacteria. The connection between people, animals, and the environment allows us to consider antimicrobial resistance in an approach within the “One Health” concept, which provides a global strategy for expanding collaboration and interdisciplinary communication. This chapter will highlight the emergence of colistin resistance, a great challenge in antimicrobial resistance field. Also, it will focus on some agents included in the priority list of superbugs of the World Health Organization (WHO) or correlated species already identified in veterinary medicine, such as the critical superbugs; priority level 1, Carbapenem-resistant Acinetobacter baumannii, Carbapenem-resistant Pseudomonas aeruginosa, and ESBL-producing Carbapenemic-resistant Enterobacteriaceae; and the high-priority, level 2, methicillin-resistant Staphylococcus aureus (MRSA)

Bacterial diversity and detection of resistance genes to broad-spectrum betalactams in dairy family farm soils

Bovine mastitis is a complex disease that brings great losses to the dairy producer. The microbial diversity of the soils, as well as the presence of resistance genes in the environment directly influence the maintenance of mastitis in the farm. The objective of this work was to analyze the bacterial diversity in pasture soils of a dairy family farm, detecting enterobacteria that may be involved in the etiology of bovine mastitis, and to detect genes that encode broad-spectrum betalactamases in these soils. Twelve soil samples, representative of different areas of the farm located in the municipality of Barra do Piraí, Rio de Janeiro, were collected at different times of the year. Total DNA was extracted from the samples, gene amplified by Nested-PCR and then the amplification products were separated by DGGE (Denaturing Gradient Gel Electrophoresis). With the DGGE it was possible to construct dendograms that effectively represented the bacterial diversity of these soils. Eight of the soil samples were used to amplify the genes encoding the betalactamase enzymes TEM (blaTEM gene), SHV (blaSHV gene) and CTX (blaCTXM gene). In three of the eight soil samples, the blaSHV gene was found to be present. The blaTEM and blaCTX-M genes were not detected in any of the samples. The detection of genes encoding broad-spectrum betalactamases in dairy cattle pasture soils is of concern, because the transfer of gene material between pathogenic and non-pathogenic bacteria in this environment is a reality

Production of extended-spectrum beta-lactamases in Escherichia coli isolated from poultry in Rio de Janeiro, Brazil

The overuse of antimicrobials in poultry has led to the development and dissemination of multidrug-resistant bacteria in the poultry industry. One of the most effective mechanisms of resistance found in Escherichia coli is the production of extended-spectrum β-lactamases (ESBL); there are several ESBLs, including the TEM, SHV, and CTX-M families. This resistance mechanism and the risks associated with transmitting these resistant microorganisms between animals, the environment, and humans can occur through direct contact and consumption of infected animals. This study aimed to determine the prevalence of E. coli in samples isolated from three broiler farms in Rio de Janeiro, Brazil, and screen the isolates for ESBL genes. The findings of this study demonstrated the presence of ESBL-producing E. coli in all farms studied. The findings of this study highlight the urgency for a program to monitor the poultry industry value chains at the regional level to control the spread of antimicrobial resistance. Therefore, we recommend that the enzyme subtypes produced by bacterial isolates should be determined to effectively characterize the distribution of genes related to antimicrobial resistance

Mapeamento do perfil de resistência e detecção do gene mecA em Staphylococcus aureus e Staphylococcus intermedius oxacilina-resistentes isolados de espécies humanas e animais Resistance pattern and detection of mecA gene in oxacillin-resistant isolates of Staphylococcus aureus and Staphylococcus intermedius from animal and human samples

Espécies de Staphylococcus spp resistentes a antimicrobianos representam um problema cosmopolita, sendo o controle de sua disseminação um importante desafio. O perfil de resistência a antimicrobianos de isolados de Staphylococcus aureus e Staphylococcus intermedius em amostras clínicas humanas e animais foi avaliado através do método de difusão em disco, no qual foi possível detectar um elevado nível de resistência à ampicilina e à penicilina. A avaliação da resistência à oxacilina, devido à heterogeneidade de resposta do gênero estudado, foi desenvolvida também através das seguintes técnicas: difusão em ágar modificado, ágar screen e microdiluição em caldo, e posteriormente correlacionada com a detecção do gene mecA, pela técnica de PCR, nas amostras consideradas resistentes em pelo menos um dos testes utilizados. A correlação entre os resultados obtidos nos testes fenotípicos com a presença do gene de resistência, considerado um método de referência, foi utilizada para validar a sensibilidade destes. De um total de 80 amostras avaliadas, 28 apresentaram resistência à oxacilina, sendo possível detectar a presença do gene de resistência mecA em 12 destas amostras. Os testes de suscetibilidade à oxacilina apresentaram sensibilidade superior a 50,0%, sendo a difusão em disco simples e o ágar screen considerados mais sensíveis, e a difusão em disco modificada, o de menor sensibilidade.Antimicrobial resistant Staphylococcus species represent an important cosmopolitan problem, and its spreading control is a significative challenge. Resistance pattern of Staphylococcus aureus and Staphylococcus intermedius species isolated from animals and humans clinical samples to different antibiotics was evaluated through disk diffusion method, where ampicillin and penicillin presented the highest level of resistance. The evaluation of the resistance to oxacillin, due to the heterogeneity of the response of the studied genus was carried out through the following tests: modified agar diffusion, agar screen and microdilution, and further correlation with the detection of mecA gene in samples that showed resistance in at least one of the susceptibility tests used. The correlation between the results obtained from phenotypic methods and the detection of resistance gene, considered as a reference method, was used in order to validate its sensitivity. Eighty clinical staphylococcal isolates (29 human and 51 animal isolates) were evaluated, 28 were oxacillin-resistant, mecA gene being detected in 12 samples. Susceptibility assessment tests to oxacillin presented above 50% of specificity, disk diffusion and agar screen being the most sensitive one, while modified disk diffusion presented the lowest sensibility rate. Ampicillin and penicillin presented the highest level of resistance

Revisão: Produção de β-lactamases do Tipo AmpC em Enterobacteriaceae

β-lactameses do tipo AmpC são importantes enzimas produzidas de forma constitutiva ou induzida, através da expressão de genes cromossomais ou plasmidiais, por membros da família Enterobacteriaceae e outras Gram negativas. Sua importância clínica reside no fato de que isolados produtores deste tipo de β-lactamase hidrolisam a maioria dos antimicrobianos β-lactâmicos, incluindo cefalosporinas, cefamicinas, penicilinas e as combinações com inibidores de β-lactamases (ESBL), limitando as opções terapêuticas para tratamento de infecções causadas por estas bactérias. Para agravar este cenário, as mutações que causam alterações nas sequências de aminoácidos, consequentemente modificam a estrutura enzimática, o que promove o surgimento de AmpC de espectro entendido (ESAC) que é capaz de hidrolisar cefalosporinas de quarta geração e carbapenêmicos, e que já foi detectada em rebanho bovino. Pequenas diferenças na sequência de aminoácidos deram origem às famílias e tipos de AmpC, sendo CMY2 prevalente em isolados oriundos de animais de companhia e de produção em todos os continentes. Presença de AmpC está frequentemente associada à multirresistência, uma vez que genes de resistência às mais variadas classes de antimicrobianos, por exemplo aminoglicosídeos, quinolonas, sulfonamidas e tetraciclinas, além de genes codificadores de outras β-lactamases, podem estar presentes em um mesmo plasmídeo. O número de agentes antimicrobianos seguramente efetivos contra esses isolados é limitado e muitos deles não estão disponíveis ou não são aprovados para uso animal. Diferentes métodos de detecção estão disponíveis, no entanto a ausência de padronização internacional tem limitado a notificação de AmpC pelos laboratórios clínicos, o que pode subestimar este mecanismo de resistência

Methicillin-resistant Staphylococcus pseudintermedius: an underestimated risk at pet clinic

The prevalence of methicillin-resistant Staphylococcus pseudintermedius (MRSP) as a cause of infectious disease in companion animals remains unknown. The emergence of MRSP is a challenge in veterinary medicine as multidrug-resistant strains began to emerge, resulting in treatment failures. This study provides an overview of the characterization of S. pseudintermedius strains from clinical pet samples and the prevalence of MRSP strains. A total of 123 S. pseudintermedius strains were characterized by phenotypic testing and the MALDI-TOF technique and evaluated for susceptibility to methicillin and the presence of the mecA gene. Of these, 49 (39.8%) were identified as MRSP. The results confirm the importance of monitoring resistant pathogens and the need for further studies to determine the prevalence of MRSP in companion animals. The prevalence of methicillin-resistant Staphylococcus pseudintermedius (MRSP) as a cause of infectious disease in companion animals remains unknown. The emergence of MRSP is a challenge in veterinary medicine as multidrug-resistant strains began to emerge, resulting in treatment failures. This study provides an overview of the characterization of S. pseudintermedius strains from clinical pet samples and the prevalence of MRSP strains. A total of 123 S. pseudintermedius strains were characterized by phenotypic testing and the MALDI-TOF technique and evaluated for susceptibility to methicillin and the presence of the mecA gene. Of these, 49 (39.8%) were identified as MRSP. The results confirm the importance of monitoring resistant pathogens and the need for further studies to determine the prevalence of MRSP in companion animals

Biofilm production and beta-lactamic resistance in Brazilian Staphylococcus aureus isolates from bovine mastitis

Submitted by Sandra Infurna ([email protected]) on 2017-07-05T12:43:52Z No. of bitstreams: 1 helene_barbosa_etal_IOC_2017.pdf: 2216959 bytes, checksum: 4e795341de226c742692ef9385f93e6f (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2017-07-05T12:56:49Z (GMT) No. of bitstreams: 1 helene_barbosa_etal_IOC_2017.pdf: 2216959 bytes, checksum: 4e795341de226c742692ef9385f93e6f (MD5)Made available in DSpace on 2017-07-05T12:56:49Z (GMT). No. of bitstreams: 1 helene_barbosa_etal_IOC_2017.pdf: 2216959 bytes, checksum: 4e795341de226c742692ef9385f93e6f (MD5) Previous issue date: 2017Universidade Federal Rural do Rio de Janeiro. Microbiologia e Imunologia Veterinária. Seropédica, RJ, Brasil.Universidade Federal Rural do Rio de Janeiro. Microbiologia e Imunologia Veterinária. Seropédica, RJ, Brasil.Universidade Federal Rural do Rio de Janeiro. Microbiologia e Imunologia Veterinária. Seropédica, RJ, Brasil.Universidade Federal Rural do Rio de Janeiro. Microbiologia e Imunologia Veterinária. Seropédica, RJ, Brasil.Universidade Federal Rural do Rio de Janeiro. Microbiologia e Imunologia Veterinária. Seropédica. Instituto de Veterinária (IV).Seropédica, RJ, Brasil.Universidade Federal Rural do Rio de Janeiro. Microbiologia e Imunologia Veterinária. Seropédica, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ. Brasil.Universidade Federal Rural do Rio de Janeiro. Microbiologia e Imunologia Veterinária. Seropédica, RJ, Brasil.Staphylococcus spp. play an important role in the etiology of bovine mastitis. Staphylococcus aureus is considered the most relevant species due to the production of virulence factors such as slime, which is required for biofilm formation. This study aimed to evaluate biofilm production and its possible relation to beta-lactamic resistance in 20 S. aureus isolates from bovine mastitic milk. The isolates were characterized by pheno-genotypic and MALDI TOF-MS assays and tested for genes such as icaA, icaD, bap, agr RNAIII, agr I, agr II, agr III, and agr IV, which are related to slime production and its regulation. Biofilm production in microplates was evaluated considering the intervals determined along the bacterial growth curve. In addition, to determine the most suitable time interval for biofilm analysis, scanning electron microscopy was performed. Furthermore, genes such as mecA and blaZ that are related to beta-lactamic resistance and oxacillin susceptibility were tested. All the studied isolates were biofilm producers and mostly presented icaA and icaD. The Agr type II genes were significantly prevalent. According to the SEM, gradual changes in the bacterial arrangement were observed during biofilm formation along the growth curve phases, and the peak was reached at the stationary phase. In this study, the penicillin resistance was related to the production of beta-lactamase, and the high minimal bactericidal concentration for cefoxitin was possibly associated with biofilm protection. Therefore, further studies are warranted to better understand biofilm formation, possibly contributing to our knowledge about bacterial resistance in vivo

Genotypic characterization of Escherichia coli strains isolated from dairy cattle environment

The aim of this study was to characterize the diversity of Escherichia coli strains involved in the dispersion of virulence genes. 152 E. coli strains originated from dairy cattle environment were evaluated through phenotypic and proteomic assays. These samples were investigated for the presence of virulence genes (eaeA, stxI, stxII, ST, LT, eagg, ial) and biofilm related genes (fimH, csgA, flu)Fil: Bronzato, Greiciane França. Universidade Federal Rural Do Rio de Janeiro; BrasilFil: Bento Rodrigues, Naiara Miranda. Universidade Federal Rural Do Rio de Janeiro; BrasilFil: Pribul, Bruno Rocha. Oswaldo Cruz Institute. National Reference Laboratory for Enteric Diseases; BrasilFil: Stefaninni, Gabrielli. Universidade Federal Rural Do Rio de Janeiro; BrasilFil: Coelho, Irene da Silva. Universidade Federal Rural Do Rio de Janeiro; BrasilFil: Soares De Souza, Miliane Moreira. Universidade Federal Rural Do Rio de Janeiro; BrasilFil: Reinoso, Elina Beatríz. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; ArgentinaFil: Lasagno, Mirta Cristina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; ArgentinaFil: Oliveira Coelho, Shana de Mattos de. Universidade Federal Rural Do Rio de Janeiro; Brasi