O uso excessivo de antimicrobianos em medicina veterinária e humana tem contribuído para o surgimento e seleção de bactérias multirresistentes (MR) em animais de produção, sendo que a presença de resíduos de antibióticos em alimentos derivados constitui uma predisposição para o estabelecimento de reações alérgicas para o consumidor, e altera as características organolépticas dos alimentos. No Brasil, embora a presença de Escherichia coli produtora de β-lactamase de espectro estendido (ESBL) em avicultura, bubalinocultura e suinocultura tenha sido documentada recentemente, não há informações sobre sua prevalência em bovinocultura, que é um setor importante do agronegócio no país. Assim, o presente estudo teve como objetivo investigar a presença de linhagens de Escherichia coli produtoras de ESBLs na microbiota intestinal de bovinos de leite, em uma fazenda comercial com prática de uso rotineiro de cefalosporinas na forma terapêutica. Amostras de suabe retal foram coletadas em 95 ruminantes (lactantes e adultos saudáveis), na presença de um regime de tratamento com ceftiofur terapêutico, em uma fazenda no estado de São Paulo. As amostras foram triadas para a presença de bactérias Gram-negativas produtoras de ESBL, onde os isolados positivos foram identificados por MALDI-TOF, com posterior identificação dos genes codificando variantes ESBL, por PCR e sequenciamento. A presença de cepas de E. coli multirresistentes (resistência a >= 3 classes de antibióticos) foi confirmada em 45 ruminantes (47,3%). Adicionalmente, foram identificadas 68 cepas de E. coli produtoras de ESBL (71,5%), sendo 7 portadoras do gene blaCTX-M-2, 11 portadoras do gene blaCTX-M-8, e 50 portadoras do gene blaCTX-M-15. As cepas de E. coli produtoras de CTX-M-15 foram clonalmente relacionadas por ERIC-PCR e PFGE, confirmando-se a presença de linhagens clonais em diferentes animais, na mesma propriedade. Quatro cepas representativas deste clone tiveram seus genomas sequenciados, demonstrando pertencer ao complexo clonal 23 (ST90), mundialmente reportado em animais e humanos. Estes resultados denotam uma alta prevalência de E. coli produtora de ESBL do tipo CTX-M na microbiota intestinal do gado leiteiro, com predominância de clones de importância clínica humana e veterinária, que hipoteticamente possuem uma genética que favorece sua adaptação (provavelmente favorecida pela pressão seletiva de antibióticos) na interface animal-humana, o que representa um potencial zoonótico de importância para a saúde pública. / The excessive use of antimicrobials in veterinary medicine has contributed to the emergence and selection of multiresistant (MR) bacteria in livestock animals, and the presence of residues of antibiotics in food products is a predisposition for the establishment of allergic reactions to the consumer, changing the organoleptic characteristics of food. In Brazil, although the presence of Escherichia coli-producing extended-spectrum β-lactamase (ESBL) in poultry, buffalo and swine farming has been documented recently, there is no information on its prevalence in cattle breeding, which is an important sector of agribusiness in the country. Thus, the present study aimed to investigate the presence of Escherichia coli strains producing ESBLs in the intestinal microbiota of dairy cattle in a commercial farm with routine practice of cephalosporins in the therapeutic form. Rectal swab samples were collected from 95 ruminants (healthy calf and adults) in the presence of a treatment regimen with ceftiofur therapeutic, on a farm in the state of São Paulo. The samples were screened for the presence of ESBL-producing Gram-negative bacteria, where positive isolates were identified by MALDI-TOF, with subsequent identification of genes encoding ESBL variants, by PCR and sequencing. The presence of multiresistant strains of E. coli (resistance to >= 3 classes of antibiotics) was confirmed in 45 ruminants (47.3%). In addition, 68 ESBL-producing E. coli strains (71.5%) were identified, 7 of which were carriers of the blaCTX-M-2 gene, 11 carriers of the blaCTX-M-8 gene, and 50 carriers of the blaCTX-M-15. The E. coli strains producing CTX-M-15 were clonally related by ERIC-PCR and PFGE, confirming the presence of clonal lineages in different animals, on the same property. Four representative strains of this clone had their genomes sequenced, demonstrating belonging to the clonal complex 23 (ST90), worldwide reported in animals and humans. These results indicate a high prevalence of E. coli producing CTX-M ESBL in the intestinal microbiota of dairy cattle, with a predominance of clones of human and veterinary clinical importance, which hypothetically have a genetics that favors their adaptation (probably favored by the selective pressure of antibiotics) at the animal-human interface, which represents a zoonotic potential of public health importance.

Entre as ß-lactamases, as enzimas CTX-M têm despertado atenção especial pela alta incidência e grande capacidade de propagação. Eventos como recombinação gênica, transferência plasmideal e multirresistência podem ser a razão da manutenção e da ampla disseminação dos genes blaCTX-M. Este é um trabalho retrospectivo que teve como objetivo caracterizar genes blaCTX-M presentes em Klebsiella spp. Foram estudadas 27 linhagens de Klebsiella pneumoniae e 8 linhagens de Klebsiella oxytoca, produtoras de ?-lactamase de espectro estendido, isoladas de pacientes hospitalizados no período de janeiro a junho de 2000. A detecção e identificação dos genes blaCTX-M, assim como dos elementos relacionados com a mobilização destes genes, foi realizada por PCR e seqüenciamento. A localização genética e a mobilidade dos genes blaCTX-M foram pesquisadas por análise plasmideal e hibridação e por conjugação. Os perfis de sensibilidade das linhagens estudadas e das linhagens transconjugantes foram comparados pela determinação da concentração inibitória mínima de antibióticos das classes das cefalosporinas, cefamicinas, aminoglicosídeos e quinolonas. Foram encontrados genes blaCTX-M em plasmídeos conjugativos em 13 (37%) linhagens estudadas: blaCTX-M-9 em 4 K. oxytoca, e blaCTX-M-2 em 9 K. pneumoniae. Os genes blaCTX-M-9 estavam associados ao elemento de inserção ISEcp1, enquanto os genes blaCTX-M-2 estavam associados a integrons de classe I contendo ISCR1. O genes blaCTX-M-2, carreado por plasmídeo, pode estar relacionado com disseminação horizontal entre vários clones de K. pneumoniae, enquanto o gene blaCTX-M-9 foi encontrado sendo carreado por um único clone de K. oxytoca. Este estudo determinou a incidência e a diversidade de enzimas CTX-M no período estudado, além de fornecer dados epidemiológicos que podem explicar a sua prevalência no mundo e contribuir para o entendimento e controle da disseminação deste tipo de resistência. / CTX-M enzymes, the world\'s most prevalent ß-lactamases disseminate very easily. Genetic recombination, plasmid transference and multiresistance could be responsible for the wide spread of blaCTM-X genes. This retrospective study aims to characterize blaCTX-M genes found in Klebsiella spp. The strains were isolated in hospital patients from January to June 2000 and consisted of 27 ESBL-producing Klebsiella pneumoniae and 8 ESBL-producing Klebsiella oxytoca. PCR and sequencing were used in the detection and identification of blaCTX-M genes and genetic elements associated with their mobilization. Determination of genetic localization and mobility of blaCTX-M genes was by plasmid analyses, hybridization and transfer assays. The minimal inhibitory concentrations (MICs) of cephalosporins, cefamicins, aminoglycosides and quinolone antimicrobials evaluated the antibiotic susceptibility profile of transconjugants and strains in the study. The blaCTX-M genes were found in 13 strains (37%): blaCTX-M-9 in 4 K. oxytoca and blaCTX-M-2 in 9 K. pneumoniae. The insertion sequence ISEcp1 was associated with blaCTX-M-9 and blaCTX-M-2 was found in a class I integron bearing ISCR1. Plasmid blaCTX-M-2 genes dissemination was due to horizontal transfer among many K. pneumoniae clones, while blaCTX-M-9 dissemination was associated with a particular clone of K. oxytoca. The study characterized incidence and diversity of CTX-M enzymes during the period studied. Moreover it showed epidemiological data, which may explain CTX-M prevalence worldwide and contribute for the understanding and control of the resistance spread.

Escherichia coli and Klebsiella pneumoniae cause a wide range of infections. Multidrug-resistance strains carrying extended-spectrum β-lactamases (ESBLs) has become a growing problem worldwide. The CTX-M type ESBLs has emerged distinctly, especially in Escherichia coli and Klebsiella pneumoniae. CTX-M type has been associated with many outbreaks of infections both in the hospitals and community. CTX-M-15 is now identified as the most predominantly distributed CTX-M enzyme. Clonal outbreaks of CTX-M-15 producing Enterobacteriaceae have been described in many countries including the United Kingdom, and Escherichia coli is the most commonly involved species. A total of 100 isolates were received in 2010 from London St George’s hospital, England, 50 Escherichia coli, 17 Klebsiella spp, 9 Enterobacter spp, 13 Proteus spp, 6 Lactose fermenting coliforms, 2 Pantoea spp, one Serratia marcescens, one Morganella morganii, and one Hafnia alvei. The antimicrobial susceptibility results showed that 5 Escherichia coli and one Klebsiella pneumoniae isolates were found to be resistance to cefotaxime, ceftazidime, ceftriaxone, cefotaxime, ciprofloxacin, and gentamicin, making them multi-drug resistant bacteria. None of the isolates showed resistance to imipenem, ertapenem, or morepenem, thus making carbapenems the drug of choice for the treatment of these infections due to multi-resistant isolates. The overall frequency of CTX-M-15 type ESBL-producers detected in this study was 6 (6%) most of them 5/6 (83%) were from Escherichia coli and one was (17%) Klebsiella pneumoniae isolates. The 6 CTX-M-positive isolates were typed by PFGE, only two strains of Escherichia coli showed more than 85% similarity, owing to clonal homology for both strains. The rest strains showed less than 85% similarity. S1 nuclease plasmid profiles were obtained for ESBL-producers isolates. A total of one to three plasmids per isolate, ranging from approximately 78.0 to 152.0 kb, were observed. The plasmids from most isolates were assigned to be IncFA and IncFB replicons. Analysis of phylogenetic groups showed group A and group B2. The method of phylogenetic classification of exteraintestinal pathogenic Escherichia coli depends on examine and combination of two preserved genes (chuaA and yjaA) and the DNA fragment TSP. Primer walking and PCR experiments were used for the genetic environment studies which showed 5 different genetic constructions for the described blaCTX-M-15 genes. Conjugation studies were used to detect the transferability of the plasmids harbouring the reported blaCTX-M-15 genes. Three isolates were found transferable by conjugation. In conclusion, this study reports the presence of hospital highly resistant blaCTX-M-15 in St George’s hospital. The spread of blaCTX-M-15 is probably due to horizontal gene transfer harbouring ISEcp1 and the conjugative properties of plasmids carrying blaCTX-M-15.

Klebsiella spp. are opportunistic pathogens that cause hospital and community acquired infections such as pneumonia, urinary tract infection, septicaemia, soft tissue infections, liver abscess, and meningitis. Multidrug-resistant strains possessing extended-spectrum β-lactamases (ESBLs) has become an increasing problem worldwide. The over use and, in some cases, misuse of antibiotics in humans and in animal husbandry has been cited as a responsible factor in the development of drug resistance in all bacterial species. The advancing age; female gender, hospital crossinfection, the food chain trade and human migrations have contributed to increase the risk for community-acquired ESBL. A total of 223 isolates collected in 2006 and 2007 at Royal Infirmary of Edinburgh, Scotland, 219 K. pneumoniae, 2 K. oxytoca, 1 Enterobacter cloacae, and one isolate Salmonella enterica were identified by API 20E and confirmed genotypically with gyrA PCR-RFLP method. The antimicrobial susceptibility results showed that 34 (15.2%), 36 (16.1%), 35 (15.7%), 45 (20.2%), 30 (13.5%) and 55 (24.7%) of these strains were found to be resistant to cefotaxime, ceftazidime, ceftriaxone, naladixic acid, ciprofloxacin and cefoxitin. None of the isolates were found resistant to meropenem keeping carbapenems the drug of choice for the treatment of multiresistant isolates. The overall frequency of ESBL producers observed in this study was 35 (15.7%) most of them 32/35 (91.4%) were from K. pneumoniae. The genetic analysis showed that SHV β-lactamases were detected in 32, whereas TEM and CTX-M were detected in 24 and 16 respectively. From the ESBL-producing isolates, molecular methods identified nine strains possessing ESBL-SHV genes (1 strain blaSHV-5, 1 strain blaSHV-80 and 8 strains blaSHV-12), whereas the remaining were from the “non-ESBL” producing strains. Conjugation methods demonstrated that 29/32 isolates harboured transferable blaSHV genes. The large SHV transposon-borne promoters were amplified from only one non-transferable blaSHV-11, 15 isolates produced the small SHV transposon-borne promoters. Furthermore, the IS26 was found 73bp upstream of the blaSHV gene in all small SHV transposon-borne promoters. A new blaLEN gene was identified from K. pneumoniae (KpII) phylogenetic group but remained susceptible to all cephalosporins. Sixteen (7.3%) of K. pneumoniae isolates were found to be producers of the CTX-M- 15 ESBL, of which two isolates (12.5%) were reported to be from communityacquired infections. The insertion sequence ISEcp1 was detected by sequencing 48 nucleotides upstream of blaCTX-M-15 in all isolates but one. Five different clones of CTX-M-15-producing isolates were identified by PFGE. The findings indicated a higher prevalence of qnr genes than in previous studies but still low in general. By PCR, 18 (8%) (11 qnrB1, 2 qnrB6 and 5 qnrA1) genes were identified from K. pneumoniae isolates. Also, the findings indicated the frequent coexpression of fluoroquinolones and ESBLs resistance in the same isolate. Two K. oxytoca strains were isolated from urine and blood specimens of hospitalized patients. Both strains were positive for the blaOXY-2 gene. One strain showed resistance to pencillins, monbactams, cephalosporins including cefotaxime and ceftazidime but was not inhibited by clavulanic acid. It differed by an amino acid substitution Ala237→Thr, which enhances the binding of cefotaxime. S1-nuclease plasmid profiles were obtained for some isolates. A total of one to two plasmids, ranging in size from approximately 40 to 210 kb, were observed per strain. The plasmids from 24 ESBL K. pneumoniae strains were assigned to be IncN or IncFII replicons. Analysis of phylogenetic groups showed that the majority of K. pneumoniae isolates were belonged to KpI-type. Both K. oxytoca strains were assigned to be KoII phylogenetic group based on rpoB and gyrA sequencing. Integrons are capable of capturing and mobilizing genes called gene cassettes which play an important role in the dissemination of antimicrobial resistance through horizontal transmission. In fact, the present study indicated a high frequency of occurrence of class 1 integrons among ESBL-positive K pneumoniae. Three isolates positive for class 1 integrons were found positive for class 2 integrons as well. Class 1 integrons including dfr, aadA and ereA2 gene cassettes have been identified by sequencing, which confer resistance to trimethoprim, streptomycin/spectinomycin and erythromycin respectively. In conclusion, the results from this thesis report the emergence of hospital and community-acquired highly resistant CTX-15 β-lactamase in the Edinburgh, Scotland. The prevalence of ESBL-producing isolates in Scotland is still much lower than in many other European countries. The dissemination of SHV- and TEM- β- lactamase types in this study is more predominate than CTX-M-15.

Class of 2012 Abstract / Specific Aims: Autologous stem cell transplant (ASCT) is the current gold standard following induction therapy to improve survival of multiple myeloma (MM). Lenalidomide (LEN) is used for treatment of MM before ASCT, but exposure may impair autologous peripheral blood stem cell (PBSC) mobilization. Chemomobilization with cyclophosphamide (CTX) has not been evaluated in this setting. CTX + filgrastim was investigated to determine if LEN-associated mobilization impairment can be abrogated. Methods: 36 pts (group A=12 pts who received ≥2 cycles of LEN and group B=24 pts without LEN) were analyzed retrospectively. Baseline characteristics were matched (p>0.05 for all variables). All pts received CTX (median group B, 1.5g/m2; median group A, 3gm/m2(p=0.18)) and filgrastim 10μg/kg/day. Primary outcomes include number of CD34+ cells collected and number of leukapheresis sessions. Secondary outcomes include failure to collect CD34+ cells and total CD34+ cells collected after second leukapheresis. Main Results: Total median number of CD34+ cells collected in group B=9.15x106/kg CD34+ cells and group A=7.43x106/kg CD34+ cells (p=0.159). Median number of apheresis sessions in group B=2 and group A=3 (p=0.42). Two of 12 pts with antecedent LEN usage failed to collect while no patient without previous LEN exposure failed to collect (p=0.105). Total number of CD34+ cells collected after 2 apheresis sessions for group B=8.13x106/kg CD34+ cells and group A=3.34x106/kg CD34+ cells (p=0.06). Conclusions: Chemomobilization with CTX + filgrastim yields robust PBSC collections irrespective of antecedent lenalidomide. There was a trend towards lesser PBSC collection in LEN-treated pts.

No description available.

O objetivo deste estudo foi caracterizar bactérias multirresistentes (MDR) isoladas de cavalos saudáveis (fezes) e doentes no Brasil e na França. De março de 2012 a dezembro de 2014, amostras clínicas coletadas de cavalos saudáveis e doentes no Brasil foram selecionadas para pesquisa da presença de bactérias MDR. A investigação sobre as amostras franceses foi restria a isolados de Escherichia coli (EC) recuperados a partir de amostras clínicas coletadas entre 2014 e 2015. Nos cavalos brasileiros, a análise de amostras de fezes de animais saudáveis revelou a presença de clones de EC não relacionados pertencentes aos filogrupos A, D ou B2 que carreavam genes como: blaCTX-M-1, blaCMY-2, qnr- e genes add-tipo (amino-transferases); enquanto que nos cavalos doentes foram encontradas EC, Proteus mirabilis, Klebsiella pneumoniae, Pseudomonas aeruginosa e Serratia marcescens carreando genes blaCTX-M-15, blaCTX-M-1, rmtD 16S rRNA metilase, qnr-tipo, aac(6´)-Ib-cr e aad-tipo. Nos cavalos doentes franceses de EC MDR foram positivas para CTX-M-1, seguido de M-2- e M-9. Estes resultados destacam a importância de cavalos como um novo reservatório de bactérias MDR. / The aim of this study was to characterize multidrug-resistant (MDR) bacteria isolated from healthy and infected horses in Brazil and France. From March 2012 to December 2014, clinical samples collected from healthy and infected horses, in Brazil, were screened for the presence of MDR bacteria. Investigation on French isolates was restricted to E. coli strains recovered from clinical samples collected between 2014 and 2015. In Brazilian horses, the analysis of fecal samples from healthy animals revealed the presence of clonally unrelated A, D or B2 phylogroups of E. coli strains carrying blaCTX-M-1, blaCMY-2, qnr- and aminoglycoside adenyl transferase (aad)-type genes, whereas in infected horses, E. coli, Proteus mirabilis, Klebsiella pneumoniae, Pseudomonas aeruginosa and Serratia marcescens isolates carrying blaCTX-M-15, blaCTX-M-1, rmtD 16S rRNA methylase, qnr-type, aac(6´)-Ib-cr and aad-type genes. In French infected horses, most MDR E. coli isolates were positive for CTX-M-1-, followed by CTX-M-2- and CTX-M-9-type extended-spectrum beta-lactamases. These results highlight the importance of horses as a new reservoir of MDR bacteria.

Animais de companhia têm sido apontados como reservatórios de bactérias gram-negativas resistentes a antibióticos utilizados em medicina humana e veterinária. O objetivo deste estudo foi investigar a prevalência da resistência mediada por plasmídeos em bactérias Gram-negativas isoladas de animais de companhia no Brasil e na França, elucidando o papel potencial desses animais como portadores assintomáticos. Amostras de DNA extraídas de quatro coleções de bactérias Gram-negativas produtoras de ESBL foram analisadas por tipagem e sub-tipagem baseados em PCR, análise do polimorfismo de comprimento de fragmentos de restrição (RFLP), dimensionamento baseado em PFGE de nuclease S1 e hibridação Southern blot. Adicionalmente, isolados de Escherichia coli, Klebsiella pneumoniae e Enterobacter cloacae foram caracterizados por PFGE (Pulsed-field Gel Electrophoresis) e Multilocus Sequence Typing, agrupamento filogenético e tipagem de O25b. A presença de plasmídeos IncH12 (~600-kb) e IncFIB (~210-290-kp) carregando genes blaCTX-M-15 e blaCTX-M-9, foi confirmada entre cepas de E. coli isoladas de animais brasileiros, enquanto uma predominância de plasmídeos IncI1 (~200 kb) pertencentes ao complexo clonal (CC) CC12 contendo o gene blaCMY-2 foi observado entre linhagens de E. coli, em filogrupos de baixa virulência A e B1. A presença de plasmídeos do tipo IncHI2 (~ 600kb) carregando o gene blaCTX-M-15 foi confirmada em cepas de E. cloacae ST927 isoladas de fezes e saliva de cães assintomáticos no Brasil. Entre os animais franceses com infecções, os isolados de E. coli pertencentes ao filogrupo A, B1 e B2 apresentaram tamanho de plasmídeo IncF de ~210-290 kb, carregando principalmente genes blaCTX-M-15, além da presença de plasmídeo IncI1 carregando em sua maioria genes blaCTX-M-1, blaCTX-M-9 e blaCMY-2. Em animais franceses saudáveis, além das associações blaCTX-M-15/IncI1, blaCTX-M-1/IncFIB, blaCTX-M-14/IncF e da presença de blaCMY-2 e blaTEM-52b (não tipáveis), foi identificada uma cepa de E. coli carregando um plasmídeo IncL (~60kb) contendo o gene blaOXA-48, sendo esta a primeira descrição desse gene em animais na França. Além disso, os genes blaCTX-M-15, blaCTX-M-2 e blaCTX-M-9 foram localizados no cromossomo em cepas brasileiras e francesas, como observado por Southern blot e Sequenciamento de Nova Geração (NGS). Em resumo, em ambos os países, a prevalência de cepas positivas para a resistência tipo ESBL é grande. Os animais de companhia podem ter um papel importante na disseminação dos genes AmpC e ESBL mediados por plasmídeos. / Companion animals can be reservoirs of Gram-negative bacteria resistant to antibiotics used in human and veterinary medicine. The aim of this study was to investigate the genetic context of plasmid-mediated resistance in Gram-negative bacteria isolated from companion animals in Brazil and France, elucidating the potential role of these animals as asymptomatic carriers. DNA samples, extracted from a collection of ESBL-producing Gram-negative bacteria, were analyzed by PCR-based typing and sub-typing schemes, restriction fragment length polymorphism analysis, S1 nuclease PFGE-based sizing and Southern blot hybridization. Additionally, Escherichia coli, Klebsiella pneumoniae, and Enterobacter cloacae isolates were characterized by PFGE (Pulsed-field Gel Electrophoresis), Multilocus Sequence Typing, phylogenetic grouping and O25b typing. Presence of IncH12 (~600-kb) and IncFIB (~210-290-kp) plasmids carrying blaCTX-M-15 and blaCTX-M-9, respectively, was confirmed among E. coli strains isolated from Brazilian pets, whereas predominance of IncI1 plasmids (~200 kb) belonging to the clonal complex (CC) CC12 and carrying blaCMY-2 gene was observed among E. coli strains of low-virulence phylogrups A and B1. The presence of IncHI2-type (~ 600-kb) plasmids carrying blaCTX-M-15 gene was confirmed in E. cloacae strains ST927 isolated from feces and saliva from asymptomatic dogs in Brazil. Among French diseased companion animals, E. coli isolates belonging to phylogroup A, B1 and B2 were found carrying IncF-type plasmid with size of ~210-290-kb, which harbored mainly blaCTX-M-15 genes. In addition, presence of IncI1 plasmids carrying blaCTX-M-1, blaCTX-M-9 and blaCMY-2 genes was identified. In healthy French animals, besides associations blaCTX-M-15/IncI1, blaCTX-M-1/IncFIB, blaCTX-M-14/IncF, and the presence of blaCMY-2 and blaTEM-52b (non-typable), it was observed an E. coli strain carrying an IncL plasmid (~ 60kbp) containing the blaOXA-48 gene, representing the first description of this gene in a French dog. In addition, blaCTX-M-15, blaCTX-M-2 and blaCTX-M-9 genes were located on the chromosome in Brazilian and French strains, as observed by Southern Blot and New Generation Sequencing (NGS) analysis. In summary, in both countries, the prevalence of positive strains for ESBL-type resistance in cats and dogs is high. Companion animals may play an important role in the dissemination of the plasmid mediated AmpC and ESBL genes.

O objetivo deste estudo foi caracterizar bactérias multirresistentes (MDR) isoladas de cavalos saudáveis (fezes) e doentes no Brasil e na França. De março de 2012 a dezembro de 2014, amostras clínicas coletadas de cavalos saudáveis e doentes no Brasil foram selecionadas para pesquisa da presença de bactérias MDR. A investigação sobre as amostras franceses foi restria a isolados de Escherichia coli (EC) recuperados a partir de amostras clínicas coletadas entre 2014 e 2015. Nos cavalos brasileiros, a análise de amostras de fezes de animais saudáveis revelou a presença de clones de EC não relacionados pertencentes aos filogrupos A, D ou B2 que carreavam genes como: blaCTX-M-1, blaCMY-2, qnr- e genes add-tipo (amino-transferases); enquanto que nos cavalos doentes foram encontradas EC, Proteus mirabilis, Klebsiella pneumoniae, Pseudomonas aeruginosa e Serratia marcescens carreando genes blaCTX-M-15, blaCTX-M-1, rmtD 16S rRNA metilase, qnr-tipo, aac(6´)-Ib-cr e aad-tipo. Nos cavalos doentes franceses de EC MDR foram positivas para CTX-M-1, seguido de M-2- e M-9. Estes resultados destacam a importância de cavalos como um novo reservatório de bactérias MDR. / The aim of this study was to characterize multidrug-resistant (MDR) bacteria isolated from healthy and infected horses in Brazil and France. From March 2012 to December 2014, clinical samples collected from healthy and infected horses, in Brazil, were screened for the presence of MDR bacteria. Investigation on French isolates was restricted to E. coli strains recovered from clinical samples collected between 2014 and 2015. In Brazilian horses, the analysis of fecal samples from healthy animals revealed the presence of clonally unrelated A, D or B2 phylogroups of E. coli strains carrying blaCTX-M-1, blaCMY-2, qnr- and aminoglycoside adenyl transferase (aad)-type genes, whereas in infected horses, E. coli, Proteus mirabilis, Klebsiella pneumoniae, Pseudomonas aeruginosa and Serratia marcescens isolates carrying blaCTX-M-15, blaCTX-M-1, rmtD 16S rRNA methylase, qnr-type, aac(6´)-Ib-cr and aad-type genes. In French infected horses, most MDR E. coli isolates were positive for CTX-M-1-, followed by CTX-M-2- and CTX-M-9-type extended-spectrum beta-lactamases. These results highlight the importance of horses as a new reservoir of MDR bacteria.

303 gesunde, deutsche Freiwillige, die in 53 verschiedene Länder (meist nach Asien, Afrika und Südamerika) reisten, wurden in eine prospektive Kohortenstudie aufgenommen. Stuhlproben und Daten über potenzielle reiseassoziierte Risikofaktoren (wie Reisestil, Essgewohnheiten, Auftreten von Gastroenteritis, Hygienemaßnahmen) wurden vor und nach der Reise mittels Fragebogen gesammelt. Mittels Selektivmedien (CHROMagar™ ESBL/KPC-Platten) wurden eine Untersuchung der Stuhlproben auf extended-spectrum beta-lactamase bildende Enterobacteriaceae (ESBL-PE) und Carbapenemase bildende Enterobacteriaceae (CPE) durchgeführt. Isolate mit bestätigtem ESBL-Phänotyp wurden auf das Vorhandensein von blaCTX-M-, blaTEM-, blaSHV-, blaVIM-, blaNDM-, blaKPC- und blaOXA-48-Genen mit Hilfe von PCR-Amplifikation und -Sequenzierung getestet. Bei den Antibiotikaempfindlichkeitstests wurde mit konventioneller Mikrobouillonverdünnung gearbeitet. Die Auswertung von 205 kompletten Teilnahmen zeigte vor Reiseantritt eine ESBL-PE Prävalenzrate von 6,8% (14/205). Unter den 191 Teilnehmern, die vor der Reise ESBL-negativ getestet wurden, waren nach Reiserückkehr 58 (30,4%) mit ESBL-bildenden Escherichia coli kolonisiert und 5 Reisende (8,6%) waren zusätzlich mit ESBL-produzierenden Klebsiella pneumoniae besiedelt. Carbapenem-resistente Enterobacteriaceae wurden nicht nachgewiesen. Die molekulargenetische ESBL-Typisierung zeigte, dass 52/54 (96,6%) der E. coli und 4/4 (100%) der K. pneumoniae-Stämme, die für die Sequenzierung verfügbar waren, CTX-M-Enzyme produzierten, und zwar überwiegend CTX-M-15 (33/56, 58,9%), und 2/54 (3,7%) der E. coli-Stämme SHV-12-Enzyme bildeten. Die Reisenden nach Indien wiesen die höchste Kolonisationsrate mit ESBL-PE (11/15, 73,3%: p=0.015) auf, gefolgt von Reisenden nach Südostasien (22/46, 47,8%; p=0.038). Die Auswertung der reiseassoziierten Risikofaktoren ergab allein für das Auftreten einer Gastroenteritis eine statistische Signifikanz (p=0.011). Strikte Händehygiene und ausschließliches Konsumieren abgepackter Getränke zeigten keinen protektiven Effekt. Die ESBL-PE-Persistenzrate nach 6 Monaten lag bei 8,6% (3/35). Daraus schlossen wir, dass weltweite Anstrengungen notwendig sind, um die weitere Ausbreitung von ESBL-PE in der Bevölkerung anzugehen. Eine aktive Überwachung und Kontaktisolation ist bei Aufnahme in eine medizinische Einrichtung speziell für Patienten, die innerhalb der letzten 6 Monate nach Indien und Südostasien gereist waren, empfehlenswert.