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Background: Commensal microflora such as Escherichia coli and Enterococcus spp. are representative indicators of antimicrobial resistance (AMR) as they are part of the normal intestinal microflora and can acquire and disseminate AMR to pathogenic or zoonotic bacteria like Salmonella spp. Objective: To investigate the state of AMR among E. coli and Salmonella spp., potential pathogens in humans, isolated from cecal contents of pigs submitted to a veterinary diagnostic laboratory in Colombia from 2016 to 2019. Methods: Susceptibility testing was conducted using the Kirby-Bauer disk diffusion method according to the Clinical and Laboratory Standards Institute guidelines for antimicrobial zone diameter breakpoints. An E. coli strain (ATCC 25922) was used as the quality control organism. Isolates showing resistance to three or more antimicrobial classes were classified as multidrug-resistant (MDR) as defined by a joint group of the European Centre for Disease prevention and Control and the Center for Disease Control and Prevention of the USA. Results: A total of 112 E. coli and 192 Salmonella spp. colonies were isolated from 557 samples received between 2016 and 2019. In order of decreasing frequency, E. coli was resistant to tetracycline (100%), sulfamethoxazol-trimethoprim (97.5%), amoxicillin (86.4%), enrofloxacin (82.6%), tylosin (82.1%), doxycycline (59%), neomycin (50%), ciprofloxacin (45.5%), ceftiofur (35%), gentamicin (30%), tilmicosin (29%), and fosfomycin (12.5%). When compared with E. coli, Salmonella spp. was generally resistant to the same agents with slightly less resistance (between 10-30%) to eight of the antimicrobials tested. Salmonella spp. showed <20% resistance to three antimicrobials, as follows: neomycin (17%), gentamicin (16%), and fosfomycin (14%). Multi-resistance occurred in 68.7% (77/112) of E. coli and 70.3% (135/192) of Salmonella spp. isolates. Resistance of Salmonella spp. was alarming to all the critically important antimicrobials tested: fluoroquinolones (enrofloxacin, ciprofloxacin), ceftiofur (third- generation cephalosporin), and macrolides (tylosin). Conclusions: According to our results, there is a high level of multi- drug resistance (MDR) in E. coli and Salmonella spp. It is necessary to implement a nationwide antimicrobial resistance monitoring program in Colombia, together with proper antimicrobial prescribing guidelines for pigs. The indiscriminate use of antimicrobial growth promoters by the swine industry is generating widespread bacterial resistance and should be discontinued.
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Antecedentes: Flora comensal como espécies de Escherichia coli e Enterococcus são tipicamente escolhidas como indicadores representativos de la resistência antimicrobiana (AMR), pois fazem parte da flora intestinal normal e podem adquirir e disseminar AMR a bactérias patogênicas ou zoonóticas como Salmonella spp. Objetivo: Investigar o estado da AMR entre E. coli e Salmonella spp. isolados do conteúdo cecal de porcos colombianos submetidos ao Laboratório de Diagnóstico Veterinário de 2016 a 2019, ambos sendo patógenos potenciais em humanos. Métodos: O teste de suscetibilidade foi conduzido usando o método de difusão em disco Kirby-Bauer de acordo com as diretrizes do Instituto de Padrões Clínicos e Laboratoriais para pontos de quebra de diâmetro da zona antimicrobiana. A cepa de E. coli (ATCC 25922) foi usada como organismo de controle de qualidade. Os isolados que apresentam resistência a três ou mais classes de antimicrobianos foram classificados como multirresistentes (MDR), conforme definido por um grupo conjunto do Centro Europeu para Prevenção e Controle de Doenças e Centro para Controle e Prevenção de Doenças dos EUA. Resultados: Um total de 112 E. coli e 192 Salmonella spp. foram isolados de 557 amostras submetidas entre 2016 e 2019. Em ordem decrescente de frequência, a resistência a E. coli foi: tetraciclina (100%), sulfametoxazol-trimetoprim (97,5%), amoxicilina (86,4%), enrofloxacina (82,6%), tilosina (82,1%), doxiciclina (59%), neomicina (50%), ciprofloxacina (45,5%), ceftiofur (35%), gentamicina (30%), tilmicosina (29%) e fosfomicina (12,5%). Quando comparada com E. coli, Salmonella spp. foi geralmente resistente aos mesmos agentes com resistência ligeiramente menor (entre 10-30%) a oito dos antimicrobianos. Apenas três antimicrobianos apresentaram resistência a Salmonella spp. abaixo de 20% da seguinte forma: neomicina (17%), gentamicina (16%) e fosfomicina (14%). Multi-resistência ocorreu em 68,7% (77/112) de E. coli e 70,3% (135/192) de Salmonella spp. isolados. Resistência de Salmonella spp. foi alarmante para todos os antimicrobianos criticamente importantes testados: fluoroquinolonas (enrofloxacina, ciprofloxacina), ceftiofur (cefalosporina de terceira geração) e macrolídeos (tilosina). Conclusões: Esses resultados indicam um alto nível de resistência a múltiplos medicamentos (MDR) e que um Programa Nacional de Monitoramento da Resistência Antimicrobiana é necessário para a Colômbia, juntamente com a implementação de diretrizes de prescrição de antimicrobianos para suínos. O uso indiscriminado de antimicrobianos para promoção de crescimento na indústria suína está claramente promovendo resistência generalizada e deve ser interrompido.
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Enteric diseases of bacterial origin are frequent in the pig industry, of particular notoriety are the colibacillosis that mainly affect piglets and cause great damage to the swine industry worldwide. The aim of the study was to analyze phylogenetics, to detect biofilm production, and to determine antimicrobial resistance profile in 126 strains of Escherichia coli isolated from swabs obtained from fragments of the small intestines of 235 healthy pigs killed in slaughterhouses in Pernambuco (Brazil) using polymerase chain reaction (PCR), adherence to microplates test and disc diffusion technique. Of the analyzed samples, 88.10% (111/126) were classified in phylogenetic group B1; 4.76% (6/126) in group D; 3.97% (5/126) in group B2 and, 3.17% (4/126) in group A. Antimicrobial resistance rates observed were: lincomycin 100% (126/126), erythromycin 100% (126/126), chlortetracycline 94.44% (119/126), cephalothin 51.59% (65/126), ampicillin 38.89% (49/126), sulfamethoxazole + trimethoprim 37.3% (47/126), ciprofloxacin 19.84% (25/126), norfloxacin 14.29% (18/126), gentamicin 8.73% (11/126) and, chloramphenicol 5.55% (7/126). Multiple antibiotic resistance (MAR) ranged from 0.2 to 0.9. Of the strains tested 46.03% (58/126) produced biofilm, and 99.21% (125/126) of the strains exhibited multi-resistance. Further studies are required to elucidate the importance of each phylogenetic group in pigs and to prevent the propagation of multi-resistant E. coli strains.(AU)
Doenças entéricas de origem bacteriana são frequentes na indústria de suínos, destacando-se a colibacilose, que afeta principalmente leitões e causa grandes danos à indústria suína em todo o mundo. Cento e vinte e seis cepas de Escherichia coli foram isoladas de swabs obtidos de fragmentos de intestino delgado de 235 suínos saudáveis abatidos em matadouros de Pernambuco (Brasil). O objetivo do presente estudo foi analisar filogeneticamente essas cepas, bem como detectar a produção de biofilme e determinar o perfil de resistência antimicrobiana delas, utilizando-se a reação em cadeia da polimerase (PCR), o teste de adesão em microplacas e a técnica de disco-difusão. 88,10% (111/126) das amostras foram classificadas no grupo filogenético B1; 4,76% (6/126) no grupo D; 3,97% (5/126) no grupo B2; e 3,17% (4/126) no grupo A. As taxas de resistência antimicrobiana observadas foram: lincomicina 100% (126/126), eritromicina 100% (126/126), clortetraciclina 94,44% (119/126), cefalotina 51,59% (65/126), ampicilina 38,89% (49/126), sulfametoxazol + trimetoprima 37,3% (47/126), ciprofloxacina 19,84% (25/126), norfloxacina 14,29% (18/126), gentamicina 8,73% (11/126) e cloranfenicol 5,55% (7/126). O índice de resistência múltipla (IRMA) variou de 0,2 a 0,9. Entre as amostras, 46,03% (58/126) produziram biofilme e 99,21% (125/126) foram multirresistentes. São necessários mais estudos para elucidar a importância de cada grupo filogenético em suínos e evitar a propagação de estirpes de E. coli multirresistentes.(AU)
Subject(s)
Animals , Biofilms , Swine/genetics , Swine/microbiology , Escherichia coli , PhylogenyABSTRACT
Objective To conclude the nursing experience in a patient with chronic pyogenic osteomyelitis of the mandible caused by multidrug-resistant bacteria. Methods Through the nursing process of patients, detailing the points of disinfection and isolation management, vacuum sealing drainage (VSD) care, drug therapy, hyperbaric oxygen therapy, strengthening primary care, psychological care of the patients with chronic pyogenic osteomyelitis of the mandible caused by multidrug-resistant bacteria. Results Illness was cured after 24 days in the hospital. Conclusions Through the nursing of a patient with chronic pyogenic osteomyelitis of the mandible caused by multidrug-resistant bacteria, reinforces the basic knowledge of nurses, improve nursing skill, which increases the theoretical basis and practical experience in clinical work.
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Corynebacterium striatum is a potentially pathogenic microorganism that causes nosocomial outbreaks. However, little is known about its virulence factors that may contribute to healthcare-associated infections (HAIs). We investigated the biofilm production on abiotic surfaces of multidrug-resistant (MDR) and multidrug-susceptible (MDS) strains of C. striatum of pulsed-field gel electrophoresis types I-MDR, II-MDR, III-MDS and IV-MDS isolated during a nosocomial outbreak in Rio de Janeiro, Brazil. The results showed that C. striatum was able to adhere to hydrophilic and hydrophobic abiotic surfaces. The C. striatum 1987/I-MDR strain, predominantly isolated from patients undergoing endotracheal intubation procedures, showed the greatest ability to adhere to all surfaces. C. striatum bound fibrinogen to its surface, which contributed to biofilm formation. Scanning electron microscopy showed the production of mature biofilms on polyurethane catheters by all pulsotypes. In conclusion, biofilm production may contribute to the establishment of HAIs caused by C. striatum.
Subject(s)
Adult , Aged , Humans , Middle Aged , Foot , Nursing Care , Surveys and QuestionnairesABSTRACT
Aim: To investigate the antimicrobial resistance profile of faecal Escherichia coli to common antimicrobial agents in healthy adults in Amassoma, South Southern Nigeria. Study Design: Cross-sectional study. Place and Duration of Study: Department of Pharmaceutical Microbiology and Biotechnology, Niger Delta University, Bayelsa State, between February and June 2010. Methodology: The stool samples collected were inoculated and screened for E. coli using standard microbiological protocols. The antimicrobial susceptibility test of the isolates was done using disc diffusion technique. Results: A total of 110 (84.6%) E. coli isolates were obtained from all the samples comprising 38 (34.5%) from the villagers and 72 (65.5%) from the University students. The overall resistance profiles of all the isolates were: ampicillin-95.5%, tetracycline- 72.7%, augmentin-70.9%, co-trimoxazole-54.5%, cefuroxime-44.5%, chloramphenicol- 39.1%, nalidixic acid-30.0%, nitrofurantoin-28.2%, ceftazidime-15.5%, ciprofloxacin- 14.5%, gentamicin-10.0% and ofloxacin-4.5%. The isolates from the villagers exhibited significantly higher resistances to some of the antibiotics than those from the students (P<0.05). The prevalence of multiple drug resistance among all the isolates was 76 (69.1%). Conclusion: The observed high level of multiple drug resistance among the flora of healthy individuals call for measures to control the sales of antimicrobial agents in this country as a strategy toward the containment of antibiotic resistance.
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Aeromonas spp. were identified in five (2,7%) of 182 diarrheal stool cultures, A. caviae was predominant, resistant mainly to ampicillin and cephalotin. This is the first study showing the presence of Aeromonas spp. in diarrheal stools of outpatients in the central region of Rio Grande do Sul State, Brazil.
Subject(s)
Humans , Ampicillin Resistance , Aeromonas/isolation & purification , Cephalothin/analysis , Cephalothin/isolation & purification , Diarrhea , Gram-Negative Bacterial Infections , Methods , OutpatientsABSTRACT
Introducción: Las infecciones por Acinetobacter baumannii se han incrementado en los últimos años en los pacientes ingresados en unidades de atención al grave lo cual ha ocasionado un incremento de la resistencia a antibióticos y de los gastos hospitalarios, mayor morbilidad y mortalidad hospitalarias. Métodos: Se estudiaron todas las cepas de Acinetobacter baumannii aisladas en los meses enero a marzo de 2010. Fueron identificadas, según la metodología del Sistema automatizado VITEK 2 compact, siguiendo las recomendaciones del fabricante (BioMÚrieux, Francia), con tarjetas ID GN, las pruebas de sensibilidad fueron realizadas con las tarjetas AST N82, con lectura automatizada. Resultados: Acinetobacter baumanni se aisló en 40 pacientes. El 77 por ciento corresponde a cepas aisladas de sangre. Se obtuvieron altos porcentajes de resistencia a todos los antibióticos beta-lactámicos, incluso con inhibidores de beta-lactamasa, la resistencia fue de 100 por ciento frente al ampicillín, 98,6 por ciento para ticarcillina-Ácido clavulánico y 66,7 por ciento para ticarcillina-tazobactam. En un lapso de 8 años ha habido un incremento del 82 por ciento de resistencia al imipenem algo similar ocurre con el meropenem. Hubo 100 por ciento de sensibilidad a la colistina y tigeciclina. Conclusión: Las cepas mostraron altos niveles de resistencia, fundamentalmente a antibióticos beta-lactámicos, incluidos carbapenémicos. La resistencia a los aminoglucósidos y las quinolonas fue extremadamente alta, sin embargo, la colistina y la tigeciclina se mantienen con 100 por ciento de sensibilidad. El principal mecanismo de resistencia encontrado fue la presencia de carbapenemasa, la cual genera un gran reto clínico, microbiológico y epidemiológico en la actividad asistencial
Introduction: The infections due to Acinetobacter baumannii have increased in past years in patients admitted in intensive care units leading to an increase of resistance to antibiotics and of hospital costs, a greater hospital morbidity and mortality. Methods: All strains of Acinetobacter baumanni isolated from January to March, 2010 were studied, identified according to the compact VITEK 2 automated system methodology, following the recommendations of manufacturer (BioMÚrieux, Francia) with ID GN cards, the sensitivity tests were carried out with AST N82 cards with automated reading. Results: Acinetobacter baumanni was isolated in 40 patients. The 77 percent correspond to strains isolated from blood. We achieve high percentages of resistance to all beta-lactamase antibiotics even with beta-lactamase inhibitors, the resistance was of 100 percent to ampicillin, of 98.6 percent to ticarcillin-clavulanic acid and of 66.7 percent to ticarcillin-tazobactan. In the interval of 8 years has been an increase of 82 percent of resistance to Imipenem as well as with the Meropenem. There was a 100 percent of sensitivity to colistine and tigecicline. Conclusions: The strains showed high levels of resistance, mainly to beta-lactamase antibiotics including the carbapenemic5 ones. The resistance to aminoglycosides and quinolones was very high; however, the colistine and the tigecicline remain with a 100 percent of sensitivity. The leading mechanism of resistance founded was the presence of carbapenemase, which is a great clinical, microbiological and epidemiological challenge in assistance activity
Subject(s)
Humans , Acinetobacter baumannii/isolation & purification , Drug Resistance, Bacterial , Carbapenems/therapeutic useABSTRACT
Introducción: Nuestro grupo ha reportado previamente una asociación entre sensibilidad a quimioterapia y la expresión de proteínas MDR (P-Gp y MRP1) en líneas celulares y cultivos primarios de cáncer de próstata, quedando por estudiar la actividad de las mismas. Material y métodos: Se utilizó líneas celulares de cáncer de próstata PC3 y DU145. Se evaluaron los niveles de mARN de P-Gp y MRP1 mediante RT-PCR. La expresión de ambas proteínas se determinó mediante inmunofluorescencia. Se estableció un ensayo funcional en base a la acumulación de sustratos fluorescentes (DiOC2(3) para P-gp y CFDA para MRP1) y al uso de inhibidores específicos para cada proteína (Ciclosporina A para P-Gp y MK571 para MRP1). Las células se incubaron durante 60 minutos a 37ºC con o sin el inhibidor específico, seguido de otra incubación por 60 minutos agregando el sustrato fluorescente. La acumulación del sustrato fluorescente se determinó por citometría de flujo. Resultados: Las líneas celulares utilizadas sólo expresaron MRP1, mientras no se detectó P-Gp (mARN ni proteína). Mediante el ensayo funcional se observó que las células acumulaban más CFDA cuando eran tratadas con MK571. No se observó diferencias en la acumulación de DiOC(2)3 frente al tratamiento con Ciclosporina A. Conclusión: La mayor acumulación intracelular de CFDA frente al tratamiento con MK571 indica que la proteína MRP1 expresada en las líneas celulares utilizadas es funcional. P-Gp no se expresa en las líneas evaluadas. En estudios en curso nos encontramos evaluando la expresión y función de ambas proteínas en cultivos primarios.
Introduction: We have previously reported an association between sensitivity to chemotherapy and the expression of multidrug resistance proteins (MDR) (P-Gp and MRP1) in cell lines and primary cultures of prostate cancer. Activity remains to be studied. Material and methods: Prostate cancer cell lines PC3 and DU145 were used. Levels of mRNA of P-Gpand MRP1 using RT-PCR, were evaluated. The expression of both proteins was determined using immunofluorescence. A functional assay based on the accumulation of fluorescence substrates (DiOC2(3) for P-Gp and CFDA for MRP1) was established. Cells were incubated for 60 minutes at 37C with/without the specific inhibitor, followed by another 60 minutes incubation adding the fluorescence substrate. Accumulation of fluorescence substrate was determined by flow citometry. Results: Cell lines expressed only MRP1, whereas P-Gp (mRNA/protein) was not detected. Using the functional assay, we found that cells accumulated more CFDA when treated with MK571. No differences were seen in the accumulation of DiOC2(3) after treatment with ciclosporin A. Conclusion: The higher intracellular accumulation of CFDA after treatment with MK571 indicates that the MRP1 protein expressed in these cell lines is functional. P-Gp was not expressed in these cell lines. We are currently evaluating the expression and function of both proteins in primary cultures.
Subject(s)
Humans , Prostatic Neoplasms , ATP Binding Cassette Transporter, Subfamily B, Member 1 , Drug TherapyABSTRACT
Los sistemas multidrogas bacterianos contribuyen al desarrollo del fenotipo de multi-resistencia presentado por cepas de Acinetobacter baumannü, patógeno intrahospi-talario, que durante los últimos años ha incrementado su importancia por la creciente resistencia a carbapenémicos. El fenotipo de multi-resistencia está otorgado por la combinación de varios mecanismos de resistencia entre los cuales se encuentran estos sistemas de bombas de expulsión. El sistema multidroga AdeABC se ha detectado en muchas de estas cepas multi-resistentes de A. baumannü y, se ha relacionado con resistencia a diversos grupos de antimicrobianos, incluidos tigeciclina y meropenem. La inhibición de dichos sistemas multidrogas permitiría aumentar la eficacia de la terapia antimicrobiana. La siguiente revisión se enfoca en las bombas de expulsión multidrogas presentes en A. baumannü, con particular énfasis en el sistema AdeABC.
Bacterial multi-drugs systems contribute to the development of multi-resistance patterns of Acinetobacter baumannii, a nosocomial pathogen of increasing importance due to its emerging resistance to carbapenems. The multi-resistance phenomena is generated by a combination of mechanisms, one of which the efflux pump system. Many of these multiresistant isolates of A. baumannii harbor genes for the AdeABC multi-drug efflux system, related with resistance to various groups of antibacterial agents, including tygecicline and meropenem. Inhibition of these systems would allow to increase the efficacy of this antimicrobial. This review focuses on the multi-drug efflux pump system oí A. baumanni with special emphasis in the AdeABC system.
Subject(s)
Acinetobacter baumannii/metabolism , Anti-Bacterial Agents/pharmacokinetics , Bacterial Proteins/metabolism , Drug Resistance, Multiple, Bacterial/physiology , Membrane Transport Proteins/metabolism , Acinetobacter baumannii/drug effects , Anti-Bacterial Agents/pharmacologyABSTRACT
OBJECTIVE To investigate the correlated resistant genes encoding ?-lactamases,aminoglycoside and genetic marker of integron and transposon in multi-resistant Pseudomonas aeruginosa(MRPA) isolated from clinical specimens and study their relationship by phylogenetic analysis.METHODS Twenty-one resistant genes,two integron-Ⅰ genes and one transposon genetic gene were analyzed by PCR and verified by DNA sequencing.Multi-resistant genes cluster analysis was performed by UPGMA.RESULTS The positive rates of CARB,oprD2,aac(3)-Ⅱ,aac(6′)-Ⅱ,ant(2″)-Ⅰ,intⅠ1,qacE△1-sul1 and merA in 20 strains of MRPA were 15%,100%,70%,15%,15%,85%,85% and 85%,respectively,and other genes were negative.It was classfied to three subgroup,by the multi-resistant genes cluster analysis.CONCLUSIONS MRPA isolated from clinical specimens has carried many resistant genes.The deficiency rate of oprD2 gene is very high.The positive rate of genetic mark genes about integron and transposon is very high.It may be the main multi-resistant mechanism of MRPA.Multi-resistant genes cluster analysis shows that there is clone transmission in MRPA and it can induce nosocomial infection prevalence.
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OBJECTIVE To investigate the production of metallo-beta-lactamase in clinical isolates of multi-resistant Pseudomonas aeruginosa and evaluate the validity of the detection methods.METHODS The multi-resistant strains were selected by K-B method according to the standard Aloush et al recommended.The metallo-beta-lactamase phenotypes were detected by multi-disk-multi-inhibitors synergy test(MDMIST),and the genotypes of IMP and VIM gene were analyzed by PCR amplification.RESULTS A total of 192 strains of multi-resistant P.aeruginosa were selected from 1081 clinical strains.The antimicrobial agents test in these multi-resistance strains demonstrated that ciprofloxacin and piperacillin had the highest resistant rate(92.5%),and the next were aztreonam and trimethoprim-sulfamethoxazole(91.5%),the polymyxin showed sensitive in all of these strains.Sixty-seven strains of metallo-beta-lactamase phenotypes were positive and the amplification PCRs showed that 65 strains were IMP or VIM in these 192 multi-resistant strains.CONCLUSIONS The resistance mechanisms in multi-resistant P.aerugionsa present multiple and changeable.The clinical laboratory should enhance the detection of metallo-beta-lactamase in these multi-resistant strains.
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OBJECTIVE To study 39 kinds of resistant-related genes in a pan-resistant Burkholderia cenocepacia(BCE) strain,in the sputum from a severe hepatitis B patient.METHODS To detect the susceptibility to antimicrobial agents by MIC,16S rRNA,39 resistant-related genes including 29 ?-lactamases genes,6 aminoglycoside-modifying enzymes(AMEs) genes,chlorhexidine/sulfadiazine resistant gene(qacE△1-sul1),integron(intⅠ1,2,3),et al,of 1 strain of BCE in the sputum from a severe hepatitis B patient,were measured by PCR,and verified by DNA sequencing.RESULTS The strain was BCE conformed by 16S rRNA-PCR-DNA sequencing.It was susceptible to ceftazidime,cefepime,ciprofloxacin,levofloxacin,and trimethoprim/sulfamethoxazole,but resistant to piperacillin,aztreonam,cefotaxime,cefoxitin,meropenem,imipenem,nitrofurantoin,gentamicin and amikacin.There were positive of 6 kinds of resistant-related genes(blaTEM-116,aac(6′)-Ⅰb,aac(3)-Ⅰ,ant(2″)-Ⅰ,ant(3″)-Ⅰ,and intⅠ1),28 kinds of ?-lactamases genes,2 kinds of AMEs genes(aac(6′)-Ⅱ and aac(3)-Ⅱ),2 kinds genes of intⅠ(intⅠ2 and intⅠ3) were negative.CONCLUSIONS The multi-resistant BCE is with its multiple resistant mechanisms,and mainly relates to 6 kinds of resistant-related genes(blaTEM-116,aac(6′)-Ⅰb,aac(3)-Ⅰ,ant(2″)-Ⅰ,ant(3″)-Ⅰ and intⅠ1.
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Objective To investigate the multi-resistance to antibiotics of clinical isolated klebsiella pneumoniae.Methods The resistance to antibiotics of clinical isolated klebsiella pneumoniae were monitored.The discconfirmatory test was used to detect extended-spectrum β-lactamases(ESBLs) and cefoxitin three-dimension was used to detect AmpC β-lactamases.Results Among the isolates there were 53 strains of ESBLs-producing bacteria (49.5% ), 30 strains of AmpC-producing bacteria(28.0%), 24 strains of ESBLs + AmpC-producing bacteria (22.46%).They were high resistance to aminoglycosides,quinolones and cephalosporins.Conclusion The multi-resistance to antibiotics of clinical isolated klebsiella pneumoniae were widespread.It is important to control nosocomial infection to strengthen the detection of the epidemiology of ESBLs and AmpC β-lactamases in clinical isolates.
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Resumen Los plásmidos conjugativos y movilizables son las estructuras extracromosomales de mayor importancia epidemiológica, responsables de la propagación horizontal de múltiples genes de resistencia. En este trabajo, se evaluaron cepas de E. coli y K. pneumoniae para determinar la presencia de plásmidos conjugativos y su relación con la adquisición, estabilización y diseminación de múltiples genes de resistencia. Utilizando ensayos de conjugación, se demostró la presencia de plásmidos conjugativos en el 67% de las cepas analizadas. El análisis del tratamiento con enzimas de restricción demostró que existen cepas bacterianas aisladas en diferentes áreas del mismo hospital que portan plásmidos con idénticos patrones de restricción. Los perfiles de resistencia de las cepas transconjugantes revelaron que se transfirieron determinantes de resistencia contra todas las familias de antibióticos analizadas, evidenciándose la contribución de los plásmidos al fenotipo de múltiple resistencia. Nuestros resultados sugieren que las cepas de E. coli y K. pneumoniae aisladas de pacientes de cuatro centros de salud del área metropolitana han podido adquirir el fenotipo de multirresistencia mediante la adquisición de plásmidos portadores de múltiples genes que codifican resistencia a diversos agentes antimicrobianos.
Abstract Conjugative and movable plasmids are the extra chromosomal structures of greater epidemiological importance, responsible for the horizontal propagation of multiple resistance genes. In this study we evaluated E. coli and K. pneunoniae strains to determine the presence of conjugative plasmids and their relationship with the acquisition, stabilization and dissemination of multiple resistance genes. Using conjugation assays we demonstrated the presence of conjugative plasmids in 67% of the strains analyzed. The analysis of restriction enzyme treatments demonstrated that there were bacterial strains isolated from different hospital areas with identical restriction patterns. The resistance profiles of the transconjugating strains revealed that there was transfer of resistance determinants against all the antibiotic families analyzed, demonstrating the plasmid contribution to the multiple resistance phenotype. Our results suggest that the E. coli and K. pneumoniae strains isolated from patients in four health centers of the metropolitan areas may have acquired the multi resistance phenotype through the acquisition of plasmids that bear multiple genes that codify resistance to various antimicrobial agents.
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OBJECTIVE To investigate the positive rate of ?-lactamase,oprD2,aminoglycosides modifying enzyme and qacE△1 gene among clinical isolated strains of multi-resistant Pseudomonas aeruginosa in our hospital.METHODS P.aeruginosa was determined by VITEK,and MIC was determined by agar dilution method.TEM,IMP,VIM,oprD2,aac(3)-Ⅱ,aac(6′)-Ⅰ,aac(6″)-Ⅱ,ant(3″)-Ⅰ,ant(2″)Ⅰ and qacE△1 in strains were detected by polymerase chain reaction(PCR).RESULTS The positive rate of TEM,aac(3)Ⅱ,aac(6′)-Ⅱ,ant(3″)-Ⅰ and ant(2″)-Ⅰ in multi-resistant P.aeruginosa were 51.4%,48.6%,40.0%,54.3%,45.7% and 60.0%,respectively.No IMP and VIM genes were detected.CONCLUSIONS Positive rate of ?-lactamase, aminoglycosides modifying enzyme is high in 35 tested strains,and that should be paid more attention.
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OBJECTIVE To study the mechanism of drug-resistance of multi-resistant Pseudomonas aeruginosa,and provide the guideline for treatment and control of P.aeruginosa infection in hospital.METHODS Fifty strains of multi-resistant P.aeruginosa were selected with K-B susceptibility method.The three-dimensional method was taken to differentiate the various beta-lactamases.The relative drug-resistance gene was detected by polymerase chain reaction(PCR).RESULTS Among 50 strains of multi-resistant P.aeruginosa,there were 2 strains(4%)producing ESBLs,20 strains(40%)producing AmpC beta-lactamases,and 11 strains(22%) producing ESBLs and AmpC beta-lactamases at the same time.There were 8 positive genes in the detected drug-resistance gene,the most common sources of gene were CTX(56%),OprD(60%) and aac(6′)-Ⅱ(60%),respectively.CONCLUSIONS The main beta-lactamases are AmpC beta-lactamases and the main genotype is CTX in the multi-resistant P.aeruginosa cultured in our area.The main course of imipenem-resistance was deletion of outer membrane proteins,and the aminoglycoside modifying enzyme gene and disinfectant-resistance gene in multi-resistant P.aeruginosa are acquired.In order to reduce the drug-resistance strains and control the infection of P.aeruginosa,antibiotics should be used reasonably according to drug susceptibility testing clinically.
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OBJECTIVE To investigate the antimicrobial-resistant genes and consanguinity in multi-resistant Pseudomonas aeruginosa(MRPA) isolated from the 98th Hospital of PLA,Huzhou,Zhejiang Province,China.METHODS Thirty strains of MRPA were isolated from hospitalized patients between Sep 2003 and Oct 2004.Twenty four kinds of genes of blaTEM,blaSHV,blaOXA-10 group,blaPER,blaVEB,blaIMP,blaVIM,blaGES,blaCARB,blaDHA,blaMIR,aac(3)-Ⅰ,aac(3)-Ⅱ,aac(3)-Ⅲ,aac(3)-Ⅳ,aac(6′)-Ⅰ,aac(6′)-Ⅱ,ant(3″)-Ⅰ,ant(2″)-Ⅰ,aph(3′)-Ⅵ,oprD,qacE△1-sul1,catB,and cml1 were analyzed by PCR and verified by DNA sequencing.Resistant-genes cluster analysis was performed by Average.RESULTS In 30 strains of MRPA the positive rate of genes of blaTEM,blaOXA-10 group,blaCARB,aac(3)-Ⅱ,aac(6′)-Ⅰ,aac(6′)-Ⅱ,ant(3″)-Ⅰ,ant(2″)-Ⅰ,qacE△1-sul1,and cml1 were 66.7%,3.3%,3.3%,76.7%,3.3%,33.3%,53.3%,26.7%,83.3%,and 3.3%,respectively,and the deficiency rate of oprD gene was 90.0%.The gene of blaOXA-10 group was sequenced and determined to be blaOXA-10 subtype ESBL gene.But the rest of genes were all negative.According to the cluster analysis of resistant-gene,30 strains of MRPA isolated could be classified into four subgroups,which were caused by the infection in hospital.CONCLUSIONS At least 10 kinds of antimicrobial-resistant genes exist in MRPA isolates,and the deficiency rate of oprD gene is very high.MRPA can induce clone transmitted hospital infection and it has fulminant prevalence.