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2.
Pol J Microbiol ; 70(3): 409-412, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34584536

RESUMO

Bronchoscopes have been linked to outbreaks of nosocomial infections. The phenotypic and genomic profiles of bronchoscope-associated Klebsiella aerogenes isolates are largely unknown. In this work, a total of 358 isolates and 13 isolates were recovered from samples after clinical procedures and samples after decontamination procedures, respectively, over the five months. Antimicrobial susceptibility testing found seven K. aerogenes isolates exhibiting a low-level resistance to antimicrobial agents. Among seven K. aerogenes isolates, we found five sequence types (STs) clustered into three main clades. Collectively, this study described for the first time the phenotypic and genomic characteristics of bronchoscope-associated K. aerogenes.


Assuntos
Broncoscópios , Enterobacter aerogenes , Genoma Bacteriano , Antibacterianos/farmacologia , Broncoscópios/microbiologia , Farmacorresistência Bacteriana , Enterobacter aerogenes/efeitos dos fármacos , Enterobacter aerogenes/genética , Enterobacter aerogenes/isolamento & purificação , Genômica
3.
Int J Antimicrob Agents ; 58(5): 106439, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34547421

RESUMO

We investigated the prevalence, resistance mechanisms and activity of ceftazidime/avibactam, meropenem/vaborbactam, imipenem/relebactam and comparator agents against carbapenem-resistant Enterobacterales (CRE) that did not carry carbapenemase genes. Among 304 CRE isolates collected in US hospitals during 2016-2018 (1.1% of the overall Enterobacterales), 45 (14.8%) isolates did not carry carbapenemases. These isolates were mainly Klebsiella aerogenes (n = 11), Enterobacter cloacae (n = 11) and Klebsiella pneumoniae (n = 10). Isolates harboured one to six ß-lactam resistance mechanisms (median, three mechanisms). Acquired ß-lactamase genes were detected in 21 isolates; blaCTX-M-15 was the most common acquired ß-lactamase gene found (14 isolates). All 11 K. aerogenes and 6 E. cloacae isolates overexpressed AmpC. Only one isolate belonging to these species carried acquired ß-lactamase genes. Disruptions or reduced expression of both outer membrane proteins (ompC/ompK36 and ompF/ompK35) were detected among 20 isolates. AcrAB-TolC was modestly expressed or overexpressed among 19 isolates from six species. One E. coli isolate produced a CTX-M-15 variant that displayed an increased meropenem minimum inhibitory concentration (MIC) when expressed in a clean background. Most ß-lactam agents had limited activity against CRE isolates that did not carry carbapenemases. Ceftazidime/avibactam inhibited all isolates, while imipenem/relebactam and meropenem/vaborbactam inhibited 93.0% (88.9% if Proteus mirabilis is included) and 93.3% of tested isolates at current breakpoints. The resistance mechanisms among CRE isolates that did not produce carbapenemases are complex; ß-lactam/ß-lactamase inhibitor combinations might have different activity against these isolates depending on their resistance mechanisms and the bacterial species.


Assuntos
Antibacterianos/farmacologia , Compostos Azabicíclicos/farmacologia , Ácidos Borônicos/farmacologia , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Ceftazidima/farmacologia , Compostos Heterocíclicos com 1 Anel/farmacologia , Imipenem/farmacologia , Meropeném/farmacologia , Inibidores de beta-Lactamases/farmacologia , Proteínas de Bactérias/metabolismo , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Combinação de Medicamentos , Farmacorresistência Bacteriana Múltipla/genética , Enterobacter aerogenes/efeitos dos fármacos , Enterobacter aerogenes/isolamento & purificação , Enterobacter cloacae/efeitos dos fármacos , Enterobacter cloacae/isolamento & purificação , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , Estados Unidos , beta-Lactamases/genética , beta-Lactamases/metabolismo
4.
Int J Antimicrob Agents ; 57(2): 106262, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33347990

RESUMO

Polymyxins were recently approved for the clinical treatment of carbapenem-resistant Enterobacteriaceae (CRE) infections in China. The aim of this study was to determine the prevalence and molecular mechanisms of polymyxin-resistant CRE prior to the clinical application of polymyxin and to evaluate the potential for emerging polymyxin resistance in China. A total of 504 unique CRE isolates were collected from six tertiary-care hospitals in China between October 2016 and September 2017. All isolates underwent antimicrobial susceptibility testing. Clinical, demographic, antimicrobial exposure and infection data were collected from patients' medical charts. PCR detection, Sanger sequencing and reverse transcription real-time fluorescence quantitative PCR (RT-qPCR) were used to investigate the molecular mechanism of polymyxin resistance. A total 19 (3.8%) polymyxin-resistant isolates were identified, including Klebsiella pneumoniae, Escherichia coli, Klebsiella aerogenes and Enterobacter cloacae. Genetic analysis in K. pneumoniae strains identified insertion sequence (IS) elements (n = 3), a stop codon (n = 1) and gene deletion (n = 2) in mgrB and a pmrB missense mutation (T157P) (n = 1). Two E. coli isolates contained mcr-1 and an E. cloacae strain harboured a frameshift in mgrB. Further transcriptional analysis showed that pmrA, pmrB, pmrC and pmrK were significantly upregulated in polymyxin-resistant isolates. Despite the lack of polymyxin exposure, 3.8% of CRE were resistant to polymyxin in China. Both chromosomal and plasmid-encoded mechanisms were identified. Our study suggests that clinical practice should be alert to pre-existing polymyxin resistance among CRE isolates to avoid further dissemination of polymyxin resistance.


Assuntos
Antibacterianos/farmacologia , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Carbapenêmicos/farmacologia , Infecções por Enterobacteriaceae/microbiologia , Polimixinas/farmacologia , Antibacterianos/uso terapêutico , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , China , Farmacorresistência Bacteriana Múltipla/genética , Enterobacter aerogenes/efeitos dos fármacos , Enterobacter aerogenes/genética , Enterobacter aerogenes/isolamento & purificação , Enterobacter cloacae/efeitos dos fármacos , Enterobacter cloacae/genética , Enterobacter cloacae/isolamento & purificação , Infecções por Enterobacteriaceae/tratamento farmacológico , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Genes Bacterianos , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , Polimixinas/uso terapêutico
6.
Int J Antimicrob Agents ; 56(1): 106011, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32417206

RESUMO

INTRODUCTION: This study examined ceftazidime-avibactam activity against carbapenem-resistant Enterobacterales (CRE) clinical isolates and resistance mechanisms among non-metallo ß-lactamase (MBL) producers displaying ceftazidime-avibactam MIC values at 4 mg/L. METHODS: CRE isolates (286 of 8161 Enterobacterales) collected in Asia-Pacific, Europe and Latin America during 2016 were screened for carbapenemase genes. Selected isolates were susceptibility tested for ceftazidime-avibactam in the presence or absence of phenylalanine-arginyl ß-naphthylamide (PAßN) and polymyxin B nonapeptide (PMBN). Genome sequences were investigated for the integrity of outer membrane protein (OMP) genes and multilocus sequence typing. qRT-PCR assays were conducted to determine expression of acrA, ampC, and OMP genes. RESULTS: Ceftazidime-avibactam inhibited 99.2% of the Enterobacterales, 22 (78.7%) of the 286 CRE and 226 (100%) non-MBL producers. Among carbapenemase producers (85.3%; 244 of 286), the most common gene was blaKPC (76 blaKPC-3 and 46 blaKPC-2), followed by blaOXA-48-like (60 isolates) and blaNDM (37). Ceftazidime-avibactam MIC values at 4 mg/L were noted among 14 Klebsiella pneumoniae (13 carrying blaKPC and 1 blaCTX-M-15) mostly from Italy and Brazil and 1 Klebsiella aerogenes overexpressing ampC. PAßN did not significantly decrease ceftazidime-avibactam results, but adding PMBN did significantly decrease the MIC results for the combination. All K. pneumoniae isolates had a premature stop codon at OmpK35 and most isolates had L3 alterations of OmpK36, low expression of this gene, or OmpC disruption (K. aerogenes). Nine K. pneumoniae isolates belonged to clonal complex 258 and displayed intrahospital clonality. CONCLUSION: Ceftazidime-avibactam is an important addition to the armamentarium against multidrug-resistant organisms, and elevated MIC results for this combination seem to be associated with L3 OmpK36 alterations and ß-lactamases able to hydrolyze ceftazidime.


Assuntos
Antibacterianos/farmacologia , Compostos Azabicíclicos/farmacologia , Proteínas de Bactérias/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Ceftazidima/farmacologia , Klebsiella pneumoniae/genética , Porinas/genética , Inibidores de beta-Lactamases/farmacologia , beta-Lactamases/genética , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Bactérias/metabolismo , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Combinação de Medicamentos , Farmacorresistência Bacteriana Múltipla/genética , Enterobacter aerogenes/efeitos dos fármacos , Enterobacter aerogenes/genética , Enterobacter aerogenes/isolamento & purificação , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , Proteínas de Membrana Transportadoras/genética , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Fenilalanina/análogos & derivados , Fenilalanina/farmacologia , Polimixina B/análogos & derivados , Polimixina B/farmacologia , beta-Lactamases/metabolismo
8.
J Postgrad Med ; 66(1): 48-50, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929312

RESUMO

Gastrointestinal mucormycosis is a rare form of invasive mucormycosis with high fatality rate due to difficulty in establishing its diagnosis. The classic risk-factors include immunosuppression and metabolic derangement. A case of ileocecal mucormycosis following intracardiac repair of congenital heart disease in a 17-year-old boy is described here who lacked the typical risk-factors for mucormycosis. Ileocecal mucormycosis affecting an individual without the classic risk-factors is uncommon.


Assuntos
Hemorragia Gastrointestinal/etiologia , Íleo/lesões , Perfuração Intestinal , Mucormicose/diagnóstico , Adolescente , Antifúngicos/uso terapêutico , Colectomia , Enterobacter aerogenes/isolamento & purificação , Cardiopatias Congênitas/cirurgia , Humanos , Klebsiella pneumoniae/isolamento & purificação , Masculino , Mucormicose/complicações , Mucormicose/tratamento farmacológico , Peritonite/tratamento farmacológico , Peritonite/microbiologia , Complicações Pós-Operatórias
9.
Microb Drug Resist ; 26(3): 284-289, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31397624

RESUMO

The emergence of blaNDM particularly in Gram-negative bacteria is a burden on the health care system in developing countries. Hence, this study was initiated to screen New Delhi Metallo-ß-lactamase (NDM)-producing Gram-negative bacterial strains from neonatal intensive care unit (NICU) of an Indian Hospital. A total of 18 blaNDM-producing isolates were detected in the present study. Out of 18 blaNDM variant isolates, 6 were Klebsiella pneumoniae, 4 Escherichia coli, 2 Enterobacter aerogenes, 1 Acinetobacter lwoffii, 1 Enterobacter cloacae, 3 Acinobacter baumannii, and 1 Cedecea davisae from NICU, showing resistance against all antibiotics, except colistin and polymixin. The transferability of resistance determinants was tested by conjugation. Transfer of blaNDM-producing strains was successful in all 18 strains. In the case of transconjugants, the minimum inhibitory concentration values were found to decrease. The blaNDM-producing isolates contained detectable plasmids of size 66, 38, and 6 kb. Plasmi/d-based replicon typing revealed the incompatibility types Inc (A/C, FIIA, FIC, K, F, W, FIA, P, X, FIB, B/O) in blaNDM-carrying isolates. This study revealed the outbreak of multiple variants of blaNDM (13 NDM-1, 4 NDM-5, and 1 NDM-7). Moreover, other resistance markers, viz. blaOXA-1, blaCMY-1, blaVIM-1, and blaSHV-1 coassociated with blaNDM were also found. In this study, we reported NDM-producing C. davisae as a first report to the best of our knowledge. This study is an attempt to reveal the dissemination of blaNDM isolated from neonates in NICU and their efficient transferability among Gram-negative bacilli through horizontal gene transfer.


Assuntos
Surtos de Doenças , Farmacorresistência Bacteriana Múltipla/genética , Transferência Genética Horizontal , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/transmissão , beta-Lactamases/genética , Acinetobacter/efeitos dos fármacos , Acinetobacter/enzimologia , Acinetobacter/genética , Acinetobacter/isolamento & purificação , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/enzimologia , Acinetobacter baumannii/genética , Acinetobacter baumannii/isolamento & purificação , Antibacterianos/farmacologia , Conjugação Genética , Enterobacter aerogenes/efeitos dos fármacos , Enterobacter aerogenes/enzimologia , Enterobacter aerogenes/genética , Enterobacter aerogenes/isolamento & purificação , Enterobacter cloacae/efeitos dos fármacos , Enterobacter cloacae/enzimologia , Enterobacter cloacae/genética , Enterobacter cloacae/isolamento & purificação , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Expressão Gênica , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Índia/epidemiologia , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , Plasmídeos
10.
Int J Antimicrob Agents ; 55(2): 105802, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31520782

RESUMO

AIMS: To undertake a prospective analysis of the occurrence of colistin-resistant and extended-spectrum ß-lactamase (ESBL)-producing Enterobacterales colonizing pigs at two farms in Portugal, and to evaluate the putative correlations with usage of different antibiotics. MATERIALS AND METHODS: One hundred and two faecal samples recovered from two different Portuguese pig farms were screened for polymyxin-resistant and ESBL-positive Enterobacterales. The authors had undertaken a study at one of the farms previously, but the use of colistin has since been banned; zinc oxide and amoxicillin are used as prophylactic and curative drugs, respectively, at this farm. The other farm included in this study used zinc oxide alone. RESULTS: Ninety-three ESBL-producing isolates (62 Escherichia coli, 29 Klebsiella pneumoniae, one Enterobacter aerogenes and one Enterobacter cloacae) and 17 colistin-resistant isolates (12 E. coli, four K. pneumoniae and one E. cloacae) were recovered. Among the ESBL producers, the majority (84%) produced CTX-M-15, while the others produced CTX-M-1 or CTX-M-9. Many different strain and plasmid backgrounds were identified, ruling out a massive dissemination of one major clone. In total, 17 colistin-resistant isolates were recovered, all from the first farm. All produced MCR-1, corresponding to 12 E. coli (10 clones) and three K. pneumoniae (two clones). The MCR-1 producers were all recovered from the farm where colistin had been used 2 years previously. CONCLUSION: This study showed a surprisingly high rate of CTX-M-15 producers at two Portuguese pig farms. A link was found between antibiotic selective pressure (ß-lactam or polymyxin) and the corresponding resistance rate.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Infecções por Enterobacteriaceae/veterinária , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Proteínas de Escherichia coli/genética , beta-Lactamases/genética , Animais , Colistina/farmacologia , Enterobacter aerogenes/efeitos dos fármacos , Enterobacter aerogenes/genética , Enterobacter aerogenes/isolamento & purificação , Enterobacter cloacae/efeitos dos fármacos , Enterobacter cloacae/genética , Enterobacter cloacae/isolamento & purificação , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/microbiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , Polimixinas/farmacologia , Portugal/epidemiologia , Estudos Prospectivos , Seleção Genética/genética , Suínos
11.
Arq. Inst. Biol ; 87: e0092020, 2020. tab
Artigo em Inglês | VETINDEX, LILACS | ID: biblio-1121090

RESUMO

Abortion and complications in reproduction are important causes of economic loss in horse breeding. Studies of its causal agents can help to identify the primary pathogens or other factors involved and define appropriate measures to reduce its occurrence. This research aimed to investigate the primary causes of equine abortion, stillbirth, and perinatal mortality in regions of Brazil. Tissue from aborted fetuses, stillbirths, neonates and foals submitted to the Biological Institute of São Paulo, Brazil, from January 2010 to July 2013 were processed for viral and bacterial isolation, polymerase chain reaction (PCR), histology, and immunohistochemistry. Bacterial infection was the primary detected cause of abortion, found in 16 of the 53 animals submitted for bacterial analysis followed by viruses analysis in 2 of 105 animals, and noninfectious causes (neonatal isoerythrolysis) in 2 of 105 animals. Fungi were found in a single sample of 53 tested. The most frequent bacteria recovered were Escherichia coli, Enterobacter aerogenes, combined E. coli and Streptococcus spp., Staphylococcus spp., and Bacillus spp. The following agents were each observed in a single sample: Arcanobacterium pyogenes, Streptococcus spp., Corynebacterium spp., Actinobacillus spp., and Rhodococcus equi. The predominant identification of fecal and other opportunistic bacteria as opposed to pathogens commonly associated with equine abortion, such as Leptospira spp. and equine herpesvirus type 1 (EHV-1), suggests the need of improving hygiene management of breeding mares to prevent bacterial infection that may cause fetal loss, stillbirth, and perinatal mortality.(AU)


Abortamento e complicações na reprodução são importantes causas de perda econômica na equideocultura. Estudos dos agentes causais podem ajudar a identificar patógenos ou outros fatores envolvidos e definir medidas apropriadas para reduzir sua ocorrência. Esta pesquisa investigou as causas primárias de aborto, natimortalidade e mortalidade perinatal em equinos de diversas regiões do Brasil. Tecidos de fetos abortados, natimortos e potros submetidos ao Instituto Biológico de São Paulo, Brasil, no período de janeiro de 2010 a julho de 2013, foram processados por meio de técnicas de isolamento viral e bacteriano, PCR, histologia e imuno-histoquímica. Infecção bacteriana foi a causa mais detectada, encontrada em 16 de 53 amostras submetidas à análise bacteriana, seguida de causa viral em 2 de 105 amostras, e causas não infecciosas (isoeritrólise neonatal) em 2 de 105 amostras. Fungo foi encontrado em uma única amostra de 53 testadas. As bactérias isoladas mais frequentemente foram Escherichia coli, Enterobacter aerogenes, E. coli associada a Streptococcus spp., Staphylococcus spp. associado a Bacillus spp. Os seguintes agentes foram observados em uma única amostra cada: Arcanobacterium pyogenes, Streptococcus spp., Corynebacterium spp., Actinobacillus spp. e Rhodococcus equi. A identificação predominante de bactérias fecais e outras bactérias oportunistas, ao invés de outros patógenos comumente associados a quadros de abortamento equino, tais como Leptospira spp. e Herpesvírus equino tipo 1, sugere a necessidade de maior atenção no manejo higiênico das éguas em reprodução, a fim de prevenir infecções bacterianas que possam causar perda fetal, natimortalidade e mortalidade perinatal.(AU)


Assuntos
Animais , Feminino , Gravidez , Infecções Bacterianas/complicações , Aborto Animal/etiologia , Cavalos , Staphylococcus/isolamento & purificação , Streptococcus/isolamento & purificação , Infecções Bacterianas/diagnóstico , Brasil , Viroses/complicações , Viroses/diagnóstico , Imuno-Histoquímica , Reação em Cadeia da Polimerase , Causas de Morte , Enterobacter aerogenes/isolamento & purificação , Aborto Animal/mortalidade , Feto Abortado , Escherichia coli/isolamento & purificação , Micoses/complicações , Micoses/diagnóstico
12.
Rev Soc Bras Med Trop ; 52: e20180460, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31271617

RESUMO

INTRODUCTION: The objective of this study was to characterize genes of aminoglycoside modifying enzymes (AMEs) in colonizing and infecting isolates of E. aerogenes harboring bla KPC from patients at a public hospital in Recife-PE, Brazil. METHODS: We analyzed 29 E. aerogenes clinical isolates resistant to aminoglycosides. AMEs genes were investigated by PCR and sequencing. RESULTS: Colonizing and infecting isolates mainly presented the genetic profiles aac(3)-IIa/aph(3')-VI or ant(2")-IIa/aph(3')-VI. This is the first report of aph(3')-VI in E. aerogenes harboring bla KPC in Brazil. CONCLUSIONS: The results highlight the importance in establishing rigorous methods for the surveillance of resistance genes, especially in colonized patients.


Assuntos
Aminoglicosídeos/genética , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Enterobacter aerogenes/genética , Infecções por Enterobacteriaceae/microbiologia , Brasil , Enterobacter aerogenes/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Fenótipo , Reação em Cadeia da Polimerase
13.
Artigo em Inglês | MEDLINE | ID: mdl-31285232

RESUMO

Antibiotic tolerance, the ability to temporarily sustain viability in the presence of bactericidal antibiotics, constitutes an understudied and yet potentially widespread cause of antibiotic treatment failure. We have previously shown that the Gram-negative pathogen Vibrio cholerae can tolerate exposure to the typically bactericidal ß-lactam antibiotics by assuming a spherical morphotype devoid of detectable cell wall material. However, it is unclear how widespread ß-lactam tolerance is. Here, we tested a panel of clinically significant Gram-negative pathogens for their response to the potent, broad-spectrum carbapenem antibiotic meropenem. We show that clinical isolates of Enterobacter cloacae, Klebsiella aerogenes, and Klebsiella pneumoniae, but not Escherichia coli, exhibited moderate to high levels of tolerance of meropenem, both in laboratory growth medium and in human serum. Importantly, tolerance was mediated by cell wall-deficient spheroplasts, which readily recovered wild-type morphology and growth upon removal of antibiotic. Our results suggest that carbapenem tolerance is prevalent in clinically significant bacterial species, and we suggest that this could contribute to treatment failure associated with these organisms.


Assuntos
Antibacterianos/farmacologia , Enterobacter aerogenes/efeitos dos fármacos , Enterobacter cloacae/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Meropeném/farmacologia , Esferoplastos/efeitos dos fármacos , Andinocilina/farmacologia , Tolerância a Medicamentos , Enterobacter aerogenes/crescimento & desenvolvimento , Enterobacter aerogenes/isolamento & purificação , Enterobacter cloacae/crescimento & desenvolvimento , Enterobacter cloacae/isolamento & purificação , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/isolamento & purificação , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/microbiologia , Klebsiella pneumoniae/crescimento & desenvolvimento , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , Esferoplastos/crescimento & desenvolvimento , Esferoplastos/isolamento & purificação
14.
J Infect Public Health ; 12(6): 897-899, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31078492

RESUMO

Most of the waterborne fecal pathogens belong to the family of Gram-negative bacteria. Hence, minimal inhibitory concentrations of chlortetracycline and ciprofloxacin antibiotics towards Gram-negative representative, Enterobacter aerogenes were estimated, which were 7 µg/ml and 0.125 µg/ml, respectively. The combined antimicrobial effect of chlortetracycline and ciprofloxacin against E. aerogenes was also investigated to establish their potential interaction towards the pathogens present in water. Eventually, the water samples obtained from various drinking water treatment plants from Québec municipality were tested for the occurrence of chlortetracycline-, ciprofloxacin- and chlortetracycline/ciprofloxacin-resistant strains.


Assuntos
Antibacterianos/farmacologia , Clortetraciclina/farmacologia , Ciprofloxacina/farmacologia , Água Potável/microbiologia , Farmacorresistência Bacteriana , Enterobacter aerogenes/efeitos dos fármacos , Enterobacter aerogenes/isolamento & purificação , Testes de Sensibilidade Microbiana , Quebeque
15.
Pesqui. vet. bras ; 39(3): 201-208, Mar. 2019. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1002799

RESUMO

This study aimed to verify the presence of members from the Enterobacteriaceae family and determine antimicrobial susceptibility profiles of the isolates in canaries bred in northeastern Brazil; in addition, the presence of diarrheagenic Escherichia coli (DEC) and avian pathogenic Escherichia coli (APEC) was also verified in these birds. Samples were collected during an exhibition organized by the Brazilian Ornithological Federation in July 2015 in Fortaleza, Brazil. A total of 88 fecal samples were collected and submitted to pre-enrichment step using buffered peptone water, followed by enrichment with the following broths: brain-heart infusion, Rappaport-Vassiliadis, and Selenite-Cystine. Subsequently, aliquots were streaked on MacConkey, brilliant green and salmonella-shigella agar plates. Colonies were selected according to morphological characteristics and submitted to biochemical identification and antimicrobial susceptibility tests with disk-diffusion technique. E. coli strains were evaluated for the presence of eight DEC genes and five APEC genes through conventional polymerase chain reaction (PCR) screening. The most frequent species observed were Pantoea agglomerans (25%), Serratia liquefaciens (12.5%), and Enterobacter aerogenes (9.1%). A single rough strain of Salmonella enterica subsp. enterica was identified in one sample (1.1%). High resistance rates to amoxicillin (78.7%) and ampicillin (75.4%) were identified. Polymyxin B (9.8%), gentamycin (6.6%), and enrofloxacin (6.6%) were the most efficient antibiotics. The total number of multidrug-resistant strains (isolates resistant to more than three antimicrobial classes) was 23 (37.7%). Four E. coli strains were tested for the virulence genes, and two were positive for APEC virulence genes: one strain was positive for iutA and the other for hlyF. In conclusion, canaries in northeastern Brazil participating in exhibitions may present Salmonella spp., Escherichia coli and other enterobacteria in the intestinal microbiota with antimicrobial resistance. These results indicate that, although the E. coli strains recovered from canaries in this study have some virulence genes, they still do not fulfill all the requirements to be considered APEC.(AU)


O objetivo deste trabalho foi verificar a presença de enterobactérias e determinar o perfil de sensibilidade aos antimicrobianos dos isolados oriundos de canários belgas criados em cativeiro do Nordeste do Brasil, adicionalmente verificou-se a presença de Escherichia coli diarreiogênicas (DEC) e E. coli patogênica aviária (APEC) nesses animais. A colheita das amostras ocorreu durante uma exposição de canários belgas organizada pela Federação Ornitológica do Brasil (FOB), em julho de 2015, na cidade de Fortaleza, Ceará, Brasil. Um total de 88 amostras de fezes foram coletadas e submetidas a pré-enriquecimento utilizando água peptonada, caldo de enriquecimento Brain Heart Infusion, Rappaport-Vassiliadis e Selenito-Cistina. Fez-se triagem em placas de ágar MacConkey, Verde Brilhante e ágar Salmonella Shigella. As colônias foram selecionadas e submetidas à identificação bioquímica e susceptibilidade antimicrobiana. Estirpes de Escherichia coli foram avaliadas quanto a presença de 8 genes de virulência de DEC e cinco de APEC por reação em cadeia da polimerase convencional (PCR). As enterobactérias encontradas com maior frequência foram Pantoea agglomerans (25%), Serratia liquefaciens (12,5%) e Enterobacter aerogenes (9,1%). Uma única estirpe de Salmonella enterica subsp. enterica (rugosa) esteve presente em um dos isolados (1,1%). Altos percentuais de resistência foram encontrados para dois antibióticos: amoxicilina (78,7%) e ampicilina (75,4%). Polimixina B (9,8%), gentamicina (6,8%) e enrofloxacina (6,5%) foram os antibióticos com melhor eficiência. O total de estirpes multirresistentes (a mais de três classes de antimicrobianos) foi de 23 (37,7%). Das quatro estirpes de E. coli isoladas, duas foram positivas para os genes de APEC, sendo uma estipe para o gene iss e outra para os genes iutA e hlyF. Portanto, canários belgas criados em cativeiro no Brasil que participam de exposições podem apresentar Salmonella spp., Escherichia coli e outras enterobactérias em sua microbiota intestinal com resistência antimicrobiana. Estes resultados indicam que as estirpes de E. coli isoladas de canário belga no presente estudo apresentam alguns, mas não todos, genes de virulência para serem caracterizadas como E. coli patogênica para aves (APEC).(AU)


Assuntos
Animais , Canários/microbiologia , Resistência Microbiana a Medicamentos , Salmonella enterica/isolamento & purificação , Pantoea/isolamento & purificação , Serratia liquefaciens/isolamento & purificação , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/veterinária , Escherichia coli/isolamento & purificação , Virulência , Enterobacter aerogenes/isolamento & purificação
16.
Appl Microbiol Biotechnol ; 103(5): 2141-2153, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30613897

RESUMO

Endophytic microorganisms can metabolize organic contaminants and assist in plant growth, thus facilitating the phytoremediation of polluted environments. An endophytic bacterium capable of decoloring malachite green (MG) was isolated from the leaves of the wetland plant Suaeda salsa and was identified as Klebsiella aerogenes S27. Complete decolorization of MG (100 mg/l) was achieved in 8 h at 30 °C and pH 7.0. Ultraviolet-visible spectroscopy and Fourier-transform infrared spectroscopy analyses indicated the degradation of MG by the isolate. The enzymic assays of the strain showed the triphenylmethane reductase (TMR) activity. A gene encoding putative TMR-like protein (named as KaTMR) was cloned and heterologously expressed in Escherichia coli. KaTMR showed only 42.6-43.3% identities in amino acids compared with well-studied TMRs, and it phylogenetically formed a new branch in the family of TMRs. The degraded metabolites by recombinant KaTMR were detected by liquid chromatography-mass spectrometry, showing differences from the products of reported TMRs. The biotransformation pathway of MG was proposed. Phytotoxicity studies revealed the less-toxic nature of the degraded metabolites compared to the dye. This study presented the first report of an endophyte on the degradation and detoxification of triphenylmethane dye via a novel oxidoreductase, thus facilitating the study of the plant-endophyte symbiosis in the bioremediation processes.


Assuntos
Biodegradação Ambiental , Enterobacter aerogenes/metabolismo , Oxirredutases/metabolismo , Corantes de Rosanilina/metabolismo , Poluentes Químicos da Água/metabolismo , Biotransformação/fisiologia , Chenopodiaceae/microbiologia , Corantes/metabolismo , Enterobacter aerogenes/classificação , Enterobacter aerogenes/isolamento & purificação , Compostos de Tritil/metabolismo
17.
CEN Case Rep ; 8(1): 38-41, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30141138

RESUMO

Urinary tract infections after JJ stent insertion are among the most common complications, and the associated microorganisms carry more antibiotic resistance determinants than those found in urine prior to stent insertion. In line with the trends in healthcare epidemiology which implicate multi-resistant microorganisms in a plethora of healthcare-associated infections, prosthetic stent material also represents an ideal milieu for biofilm formation and subsequent infection development with resistant bacterial agents. Here we describe a case of a 73-year-old Caucasian woman presenting with urinary tract infection after JJ ureteric stent insertion due to ureteric obstruction and hydronephrosis of her left kidney. Extensive microbiological work-up and comprehensive molecular analysis identified the putative microorganism as carbapenem-resistant Enterobacter aerogenes carrying New Delhi metallo-beta-lactamase 1 (NDM-1). This is a first literature report implicating such extensively resistant strain of this species in early indwelling ureteric stent complications, and also the first report of NDM-1 in Enterobacter aerogenes in Croatia and Europe.


Assuntos
Enterobacter aerogenes/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Stents/microbiologia , Infecções Urinárias/microbiologia , beta-Lactamases/biossíntese , Idoso , Carbapenêmicos/farmacologia , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/etiologia , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana Múltipla , Enterobacter aerogenes/efeitos dos fármacos , Enterobacter aerogenes/metabolismo , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Enterobacteriaceae/etiologia , Feminino , Humanos , Testes de Sensibilidade Microbiana/métodos , Obstrução Ureteral/terapia , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/etiologia
18.
Rev. Soc. Bras. Med. Trop ; 52: e20180460, 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1041512

RESUMO

Abstract INTRODUCTION: The objective of this study was to characterize genes of aminoglycoside modifying enzymes (AMEs) in colonizing and infecting isolates of E. aerogenes harboring bla KPC from patients at a public hospital in Recife-PE, Brazil. METHODS: We analyzed 29 E. aerogenes clinical isolates resistant to aminoglycosides. AMEs genes were investigated by PCR and sequencing. RESULTS: Colonizing and infecting isolates mainly presented the genetic profiles aac(3)-IIa/aph(3')-VI or ant(2")-IIa/aph(3')-VI. This is the first report of aph(3')-VI in E. aerogenes harboring bla KPC in Brazil. CONCLUSIONS: The results highlight the importance in establishing rigorous methods for the surveillance of resistance genes, especially in colonized patients.


Assuntos
Humanos , Enterobacter aerogenes/genética , Farmacorresistência Bacteriana/genética , Infecções por Enterobacteriaceae/microbiologia , Aminoglicosídeos/genética , Antibacterianos/farmacologia , Fenótipo , Brasil , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Enterobacter aerogenes/isolamento & purificação
20.
J Glob Antimicrob Resist ; 14: 70-71, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29935332

RESUMO

OBJECTIVES: The draft genome sequences of two Enterobacter aerogenes strains (HN503E2II and PN108E5IIB) isolated from two Cameroonian abattoirs are reported. METHODS: Bacterial genomic DNA of the two isolates was sequenced using an Illumina MiSeq platform. Generated reads were de novo assembled using CLC Genomics Workbench and SPAdes. The assembled contigs were annotated, and antibiotic resistance genes, virulence factors and plasmids were identified. RESULTS: Whole-genome sequencing revealed that both strains were similar, with genomes of 4878638bp and 4794257bp, encoding several resistance genes associated with resistance to ß-lactams, fluoroquinolones, aminoglycosides, fosfomycin, phenicols, sulphonamides, trimethoprim, macrolides and tetracycline. In silico analysis also revealed chromosomal integration of one plasmid in the genome of PN108E5IIB. CONCLUSION: The genome sequences reported here will provide useful information for a better understanding of the genetic structure of E. aerogenes in Africa.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Enterobacter aerogenes/efeitos dos fármacos , Enterobacter aerogenes/genética , Genoma Bacteriano , Matadouros , Animais , Antibacterianos/farmacologia , Camarões , DNA Bacteriano/genética , Enterobacter aerogenes/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Feminino , Humanos , Testes de Sensibilidade Microbiana , Nariz/microbiologia , Plasmídeos/genética , Suínos , Fatores de Virulência/genética , Sequenciamento Completo do Genoma , beta-Lactamases/genética
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