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1.
Ann Lab Med ; 42(1): 36-46, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34374347

RESUMO

Background: The emergence of carbapenemase-producing Enterobacteriaceae (CPE) represents a major clinical problem. Recently, the occurrence of CPE has increased globally, but epidemiological patterns vary across region. We report the trends in the genotypic distribution and antimicrobial susceptibility of CPE isolated from rectal and clinical samples during a four-year period. Methods: Between January 2016 and December 2019, 1,254 nonduplicated CPE isolates were obtained from four university hospitals in Korea. Carbapenemase genotypes were determined by multiplex real-time PCR. Antimicrobial susceptibility was profiled using the Vitek 2 system (bioMérieux, Hazelwood, MO, USA) or MicroScan Walkaway-96 system (Siemens West Sacramento, CA, USA). The proportions of carbapenemase genotypes and nonsusceptibility were analyzed using Pearson's chi-square test. Results: Among the 1,254 CPE isolates, 486 (38.8%), 371 (29.6%), 357 (28.5%), 8 (0.6%), 8 (0.6%), and 24 (1.9%) were Klebsiella pneumoniae carbapenemase (KPC), oxacillinase (OXA)-48-like, New Delhi metallo-ß-lactamase (NDM), imipenemase (IMP), Verona integron-encoded metallo-ß-lactamase (VIM), and multiple producers, respectively. The predominant species was K. pneumoniae (72.6%), followed by Escherichia coli (6.5%). More than 90% of the isolates harboring KPC, NDM, and OXA-48-like were nonsusceptible to cephalosporins, aztreonam, and carbapenems. Conclusions: The impact of CPE is primarily due to KPC-, NDM-, and OXA-48-like-producing K. pneumoniae isolates. Isolates carrying these carbapenemase are mostly multidrug-resistant. Control strategies based on these genotypic distributions and antimicrobial susceptibilities of CPE isolates are required.


Assuntos
Anti-Infecciosos , Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Enterobacteriaceae , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Infecções por Enterobacteriaceae/epidemiologia , Genótipo , Hospitais Universitários , Humanos , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana , República da Coreia , beta-Lactamases/genética
2.
Front Cell Infect Microbiol ; 11: 688989, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34604103

RESUMO

Background: There is a paucity of studies using clinical characteristics and whole-genome sequencing together to fully identify the risk factors of patients with Klebsiella pneumoniae (KP) bloodstream infection (BSI). Methods: We retrospectively analyzed the clinical and microbiological characteristics of patients with KP BSI. Isolates were processed using Illumina NGS, and relevant bioinformatics analysis was conducted (multi-locus sequence typing, serotype, phylogenetic reconstruction, detection of antibiotic resistance, and virulence genes). A logistic regression model was used to evaluate the risk factors of hosts and causative KP isolates associated with 30-day mortality in patients infected with KP BSI. Results: Of the 79 eligible patients, the 30-day mortality rate of patients with KP BSI was 30.4%. Multivariate analysis showed that host-associated factors (increased APACHE II score and septic shock) were strongly associated with increased 30-day mortality. For the pathogenic factors, carriage of iutA (OR, 1.46; 95% CI, 1.11-1.81, p = 0.002) or Kvar_1549 (OR, 1.31; 95% CI, 1.02-1.69, p = 0.043) was an independent risk factor, especially when accompanied by a multidrug-resistant phenotype. In addition, ST11-K64 hypervirulent carbapenem-resistant KP co-harbored acquired blaKPC-2 together with iutA (76.5%, 13/17) and Kvar_1549 (100%, 17/17) genes. Comparative genomic analysis showed that they were clustered together based on a phylogenetic tree, and more virulence genes were observed in the group of ST11-K64 strains compared with ST11-non-K64. The patients infected with ST11-K64 strains were associated with relatively high mortality (47.2%, 7/17). Conclusion: The carriage of iutA and Kvar_1549 was seen to be an independent mortality risk factor in patients with KP BSI. The identification of hypervirulent and carbapenem-resistant KP strains associated with high mortality should prompt surveillance.


Assuntos
Bacteriemia , Infecções por Klebsiella , Antibacterianos/farmacologia , Humanos , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/genética , Tipagem de Sequências Multilocus , Filogenia , Estudos Retrospectivos
3.
Clin Lab ; 67(10)2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34655187

RESUMO

BACKGROUND: The emergence of carbapenem-resistant Klebsiella pneumoniae has become a major problem among healthcare-associated infections with relatively few therapeutic options. In particular, the infection of carbapen-emase-producing Enterobacteriaceae (CPE) can be related to the widespread nosocomial transmission. In this study, we isolated carbapenem-resistant K. pneumoniae producing carbapenemase from a tertiary-care hospital and investigated the antimicrobial resistance and molecular and epidemiological features of these isolates. METHODS: A total of 16 carbapenemase-producing K. pneumoniae strains were isolated from a tertiary-care hospital. Antimicrobial susceptibility tests were performed. Carbapenemase production was assessed using the phenotypic and genotypic tests. Molecular characteristics were determined using polymerase chain reaction to detect blaKPC, blaIMP-1, blaVIM, blaNDM, blaOXA48, and blaGES. For phylogenetic analyses, multilocus sequence typing (MLST) was performed. RESULTS: All of the isolates were found to be resistant to ertapenem (MIC range 2.0 - 8.0 g/mL), among which only two (12.5%) isolates were susceptible to imipenem. All isolates were resistant to ampicillin, azithromycin, cefazolin, cefepime, cefotaxime, cefoxitin, ceftazidime, and ciprofloxacin. Three isolates (18.8%) were resistant to gentamicin, and two isolates (12.5%) were resistant to amikacin. Only two isolates were identified as carbapenemase producers using the phenotypic tests. All isolates produced GES-5 carbapenemases. MLST analysis revealed four sequence types (STs): ST11 (n = 12), ST789 (n = 2), ST392 (n = 1), and an unidentified ST (n = 1). CONCLUSIONS: ST11 K. pneumoniae producing GES-5 carbapenemase was the most common sequence type. Systematic and broad range screening tests in the early stages are required to identify the carbapenemase producers, which may help to prevent healthcare-associated transmission.


Assuntos
Antibacterianos , Klebsiella pneumoniae , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Filogenia , Centros de Atenção Terciária , beta-Lactamases/genética
4.
Infectio ; 25(3): 193-196, jul.-set. 2021. tab, ilus
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1250092

RESUMO

Resumen El constante aumento de Enterobacterales productores de carbapenemasas (CPE) se constituye en un problema de salud pública a nivel mundial, por el impacto generado en la mortalidad de los pacientes. El tracto gastrointestinal es el principal reservorio de este tipo de microorganismos, por lo cual, la colonización rectal se convierte en un importante factor de riesgo para el desarrollo de posteriores infecciones. Una de las estrategias de vigilancia epidemiológica activa, es la búsqueda de pacientes colonizados, a través de cultivos de tamización para detectar estos microrganismos multirresistentes. Reportamos el caso de un paciente, con historia de sepsis de origen pulmonar, colonizado por Klebsiella pneumoniae con coproducción de carbapenemasas NDM + KPC y Escherichia coli con carbapenemasa NDM. Este hallazgo es cada vez más frecuente, lo cual implica un reto en su detección y diagnóstico. Se describen características del paciente, procedimientos realizados y hallazgos microbiológicos.


Abstract The constant increase in carbapenemase-producing Enterobacterales (CPE) constitutes a public health problem worldwide, due to the impact generated on the mortality of patients. The gastrointestinal tract is the main reservoir for this microorganism, which is why, rectal colonization becomes an important risk factor for the development of subsequent infections. One of the active epidemiological surveillance strategies is the search for colonized patients through screening cultures, to detect these multi-resistant microorganisms. We report the case of a patient, with a history of sepsis of pulmonary origin, colonized by Klebsiella pneumoniae with co-production of NDM + KPC carbapenemases and NDM carbapenemase-producing Escherichia coli. This finding is more and more frequent, which implies a challenge in its detection and diagnosis. Patient characteristics, procedures performed and microbiological findings are described.


Assuntos
Humanos , Pessoa de Meia-Idade , Enterobacteriaceae , Enterobacteriáceas Resistentes a Carbapenêmicos , Sepse , Trato Gastrointestinal , Escherichia coli , Infecções , Klebsiella pneumoniae
5.
Clin Lab ; 67(9)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34542958

RESUMO

BACKGROUND: The determination of clonal interactions between microorganisms is very important in epidemiological studies. In the present study, we aimed to evaluate the resistance mechanisms and genetic relationships of carbapenem and colistin resistant Klebsiella pneumoniae (K. pneumoniae) strains isolated from inpatients at two university hospitals in Turkey. METHODS: A total of 38 K. pneumoniae clinical isolates were included in the study. Identification of isolates was confirmed by 16S rRNA sequencing. Antimicrobial susceptibility testing was performed with VITEK-2 system (bio-Mérieux, France). Modified Hodge test was used for the detection of carbapenemase activity in isolates. Carbapenem resistance genes (blaOXA-48, blaNDM, blaKPC, blaIMP, blaVIM) and colistin resistance genes (mcr-1, mcr-2 and mcr-3) were investigated by PCR. Enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) and multilocus sequence typing (MLST) analysis were used to determine the genetic relatedness among the isolates. RESULTS: We detected that 58% of isolates were positive for only blaOXA-48, 5% were only positive for blaNDM, and 34% were positive for both blaOXA-48 and blaNDM. blaKPC, blaIMP, blaVIM, mcr-1, mcr-2, and mcr-3 were not detected among the isolates. Only one carbapenem resistant isolate was negative for the carbapenemase genes tested. A total of nine profiles were found by ERIC-PCR, and MLST results showed seven different sequence types-ST14, ST16, ST79, ST101, ST1543, ST2096, and ST2832. The seven STs were grouped by PHYLOVIZ Online into four clonal complexes. The most common ST was ST14 (81%) in Center 1 and ST2096 (94%) in Center 2. CONCLUSIONS: We determined MLST types of carbapenem and colistin resistant K. pneumoniae isolates from two different centers. Although the most common ST types were different in these centers, both ST types were clustered in CC14. To the best of our knowledge this is the first report of ST14 and ST2096 outbreaks in Turkey.


Assuntos
Infecções por Klebsiella , Klebsiella pneumoniae , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Carbapenêmicos/farmacologia , Colistina/farmacologia , Hospitais , Humanos , Infecções por Klebsiella/diagnóstico , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , RNA Ribossômico 16S , Turquia/epidemiologia , beta-Lactamases/genética
6.
Ethiop J Health Sci ; 31(3): 663-672, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34483624

RESUMO

Background: This cross-sectional study was performed on isolates of Klebsiella pneumoniae, and E.coli from clinical specimens of patients admitted to Sayyad Shirazi Hospital by census sampling method in 2019. Antibiogram testing was performed using the disk diffusion method as defined by the Clinical and Laboratory Standards Organization for performing this test. Finally, the abundance of genes was evaluated by PCR using specific primers. Frequency, percentage, mean±SD were used to describe the data. Chi-square and Fisher's exact tests were used to compare the presence and absence of the studied genes alone and in the presence of each other. Result: This study was performed on 130 positive samples, isolated from 32 (24.6%) males and 98 (65.4%) females with a mean age of 43.78 ± 21.72. From the total number of 130 isolates, 84 (64.6%) consisted of E.coli, and 46 (35.4%) were Klebsiella. Most of the cultures were urine and vaginal (61.5%). The highest antibiotic resistance in isolates was cephalexin and cefazolin (67.9% in E.coli & 63% in Klebsiella). Colistin was identified as the most effective antibiotic (100%) in both. AMPC extendedspectrum ß-lactamase genes were present in 40 (30.8%) isolates. The highest frequency about the gene pattern of AMPC positive ß-lactamase bacteria was correlated to DHA, FOX, and CIT genes, while none of the samples contained the MOX ß-lactamase gene. E.coli and Klebsiella beta-lactamase-producing AMPC isolates were also significantly correlated with antibiotic resistance to the cephalosporin class (P <0.05). Conclusion: This study indicated a high percentage of resistance to third and fourth generation cephalosporins. Hence, careful antibiogram tests and prevention of antibiotic overuse in infections caused by AMPC-producing organisms and screening of clinical samples for the resistance mentioned above genes and providing effective strategies to help diagnose and apply appropriate treatments and change antibiotic usage strategies can partially prevent the transmission of this resistance.


Assuntos
Farmacorresistência Bacteriana/genética , Escherichia coli , Klebsiella pneumoniae , Antibacterianos/farmacologia , Estudos Transversais , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Infecções por Escherichia coli/tratamento farmacológico , Feminino , Humanos , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Masculino , Testes de Sensibilidade Microbiana , beta-Lactamases/genética
7.
BMJ Case Rep ; 14(9)2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34511416

RESUMO

Primary lung abscess as a complication of necrotising community-acquired pneumonia due to multidrug-resistant (MDR) Klebsiella pneumoniae is rare. A 63-year-old man with a medical history of type 2 diabetes mellitus and chronic kidney disease was diagnosed with lung abscess due to MDR Klebsiella pneumoniae, a rare organism as a causative agent for community-acquired pneumonia. This unusual case revealed therapeutic challenges faced owing to factors such as drug-resistant pathogen, longer duration of antibiotics required for lung abscess and the chronic kidney status of the patient limiting the dosage of antibiotics. The clinical nuggets discussed in this case might pave the way in the future for management guidelines to be formulated in optimising the selection and duration of therapy for lung abscesses with MDR aetiology and in early recognition of this rare but dreaded entity.


Assuntos
Infecções Comunitárias Adquiridas , Diabetes Mellitus Tipo 2 , Infecções por Klebsiella , Abscesso Pulmonar , Antibacterianos/uso terapêutico , Infecções Comunitárias Adquiridas/diagnóstico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Infecções por Klebsiella/diagnóstico , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae , Abscesso Pulmonar/diagnóstico , Abscesso Pulmonar/tratamento farmacológico , Masculino , Pessoa de Meia-Idade
8.
BMC Infect Dis ; 21(1): 977, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34544384

RESUMO

BACKGROUND: Multidrug-resistant (MDR) Klebsiella pneumoniae infections, from pancreatic infections to bloodstream infections, influence the mortality of patients with acute pancreatitis (AP) on the condition of limited antibiotic choices. The aim of this study was to investigate the predictor of mortality among AP patients complicated with MDR-K. pneumoniae infections. METHODS: Seventy-one AP patients who occurred MDR-K. pneumoniae infections from August 1st, 2016 to August 1st, 2020 were enrolled. MDR-K. pneumoniae was defined as the K. pneumoniae strain non-susceptible to at least one agent in three or more antimicrobial categories. MDR-K. pneumoniae isolates were confirmed by Vitek-2 system. Antibiotic susceptibility test was carried out using a micro broth dilution method. Clinical characteristics and drug-resistance rates were retrospectively reviewed, and the predictors of mortality were evaluated by univariate and multivariate analyses. RESULTS: The mortality rate of AP patients complicated with MDR-K. pneumoniae infections reached 46.5% (33 of 71), and pancreas (n = 53) was the most common site of MDR-K pneumoniae strains. The drug resistance rates of MDR-K. pneumoniae were high to 11 of 12 common antibiotics (more than 50.0%) except of tigecycline (23.9%). The predictor independently associated with mortality was septic shock (hazard ratio 2.959, 95% confidence intervals 1.396 - 6.272, P = 0.005). CONCLUSIONS: More attention should be paid for pancreatic MDR-K. pneumoniae infections among AP patients The predictor for mortality of AP patients complicated with MDR-K. pneumoniae infection is septic shock. Therefore, further clinical investigations should focus on areas against septic shock.


Assuntos
Infecções por Klebsiella , Pancreatite , Doença Aguda , Farmacorresistência Bacteriana Múltipla , Humanos , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae , Pancreatite/complicações , Pancreatite/tratamento farmacológico , Estudos Retrospectivos
9.
Front Cell Infect Microbiol ; 11: 709681, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34589442

RESUMO

Background: The incidence of hypervirulent (hv) carbapenem-resistant (CR) Klebsiella pneumoniae (Kp) is increasing globally among various clones and is also responsible for nosocomial infections. The CR-hvKp is formed by the uptake of a virulence plasmid by endemic high-risk clones or by the uptake of plasmids carrying antimicrobial resistance genes by the virulent clones. Here, we describe CR-hvKp from India belonging to high-risk clones that have acquired a virulence plasmid and are phenotypically unidentified due to lack of hypermucoviscosity. Methods: Twenty-seven CRKp isolates were identified to possess rmpA2 by whole-genome sequencing; and resistance and virulence determinants were characterized. By in silico protein modeling (and validation), protein backbone stability analysis, and coarse dynamics study, the fitness of RmpA, RmpA2, and aerobactin-associated proteins-IucA and IutA, were determined to establish a reliable marker for clinical identification of CR-hvKp. Results: The CR-hvKp belonged to multidrug-resistant (MDR) high-risk clones such as CG11, CG43, ST15, and ST231 and carried OXA-232 as the predominant carbapenemase followed by NDM. The virulence plasmid belonged to IncHI1B replicon type and carried frameshifted and truncated rmpA and rmpA2. This resulted in a lack of hypermucoviscous phenotype. However, functional aerobactin was expressed in all high-risk clones. In silico analysis portrayed that IucA and IutA were more stable than classical RmpA. Furthermore, IucA and IutA had lower conformational fluctuations in the functional domains than the non-functional RmpA2, which increases the fitness cost of the latter for its maintenance and expression among CR-hvKp. Hence, RmpA and RmpA2 are likely to be lost among CR-hvKp owing to the increased fitness cost while coding for essential antimicrobial resistance and virulence factors. Conclusion: Increasing incidence of convergence of AMR and virulence is observed among K. pneumoniae globally, which warrants the need for reliable markers for identifying CR-hvKp. The presence of non-functional RmpA2 among high-risk clones highlights the significance of molecular identification of CR-hvKp. The negative string test due to non-functional RmpA2 among CR-hvKp isolates challenges phenotypic screening and faster identification of this pathotype. This can potentially be counteracted by projecting aerobactin as a stable, constitutively expressed, and functional marker for rapidly evolving CR-hvKp.


Assuntos
Infecções por Klebsiella , Klebsiella pneumoniae , Carbapenêmicos/farmacologia , Simulação por Computador , Humanos , Ácidos Hidroxâmicos , Klebsiella pneumoniae/genética
10.
Front Cell Infect Microbiol ; 11: 722536, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34504809

RESUMO

Untreated wastewater is a reservoir for multidrug-resistant bacteria, but its role in the spread of antibiotic resistance in the human population remains poorly investigated. In this study, we isolated a KPC-2-producing ST2787 Klebsiella quasipneumoniae subsp. quasipneumoniae (WW14A), recovered from raw sewage at a wastewater treatment plant in Argentina in 2018 and determined its complete genome sequence. Strain WW14A was resistant to all ß-lactams, ciprofloxacin and amikacin. A core genome phylogenetic analysis indicated that WW14A was closely related to a GES-5-producing Taiwanese strain isolated from hospital wastewater in 2015 and it was clearly distinct from strains isolated recently in Argentina and Brazil. Interestingly, bla KPC-2 was harbored by a recently described IncP-6 broad-spectrum plasmid which was sporadically reported worldwide and had never been reported before in Argentina. We investigated the presence of the IncP-6 replicon in isolates obtained from the same sampling and found a novel non-typable/IncP-6 hybrid plasmid in a newly assigned ST1407 Enterobacter asburiae (WW19C) also harboring bla KPC-2. Nanopore sequencing and hybrid assembly of strains WW14A and WW19C revealed that both IncP-6 plasmids shared 72% of coverage (~20 kb), with 99.99% of sequence similarity and each one also presented uniquely combined regions that were derived from other plasmids recently reported in different countries of South America, Asia, and Europe. The region harboring the carbapenem resistance gene (~11 kb) in both plasmids contained a Tn3 transposon disrupted by a Tn3-ISApu-flanked element and the core sequence was composed by ΔISKpn6/bla KPC-2/Δbla TEM-1/ISKpn27. Both strains also carried genes conferring resistance to heavy metals (e.g., arsenic, mercury, lead, cadmium, copper), pesticides (e.g., glyphosate), disinfectants, and several virulence-related genes, posing a potential pathogenic risk in the case of infections. This is the first study documenting bla KPC-2 associated with IncP-6 plasmids in K. quasipneumoniae and Enterobacter cloacae complex from wastewater in Argentina and highlights the circulation of IncP-6 plasmids as potential reservoirs of bla KPC-2 in the environment.


Assuntos
Esgotos , beta-Lactamases , Antibacterianos/farmacologia , Argentina , Enterobacter , Humanos , Klebsiella , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Filogenia , Plasmídeos/genética , beta-Lactamases/genética
11.
Elife ; 102021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34544549

RESUMO

Vaccination strategies for rapid protection against multidrug-resistant bacterial infection are very important, especially for hospitalized patients who have high risk of exposure to these bacteria. However, few such vaccination strategies exist due to a shortage of knowledge supporting their rapid effect. Here, we demonstrated that a single intranasal immunization of inactivated whole cell of Acinetobacter baumannii elicits rapid protection against broad A. baumannii-infected pneumonia via training of innate immune response in Rag1-/- mice. Immunization-trained alveolar macrophages (AMs) showed enhanced TNF-α production upon restimulation. Adoptive transfer of immunization-trained AMs into naive mice mediated rapid protection against infection. Elevated TLR4 expression on vaccination-trained AMs contributed to rapid protection. Moreover, immunization-induced rapid protection was also seen in Pseudomonas aeruginosa and Klebsiella pneumoniae pneumonia models, but not in Staphylococcus aureus and Streptococcus pneumoniae model. Our data reveal that a single intranasal immunization induces rapid and efficient protection against certain Gram-negative bacterial pneumonia via training AMs response, which highlights the importance and the possibility of harnessing trained immunity of AMs to design rapid-effecting vaccine.


Assuntos
Infecções por Acinetobacter/prevenção & controle , Acinetobacter baumannii/imunologia , Vacinas Bacterianas/administração & dosagem , Infecções por Klebsiella/prevenção & controle , Klebsiella pneumoniae/imunologia , Macrófagos Alveolares/efeitos dos fármacos , Pneumonia Bacteriana/prevenção & controle , Infecções por Pseudomonas/prevenção & controle , Pseudomonas aeruginosa/imunologia , Infecções por Acinetobacter/imunologia , Infecções por Acinetobacter/microbiologia , Administração Intranasal , Transferência Adotiva , Animais , Células Cultivadas , Modelos Animais de Doenças , Feminino , Proteínas de Homeodomínio/genética , Imunidade Inata/efeitos dos fármacos , Infecções por Klebsiella/imunologia , Infecções por Klebsiella/microbiologia , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/microbiologia , Macrófagos Alveolares/transplante , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pneumonia Bacteriana/imunologia , Pneumonia Bacteriana/microbiologia , Infecções por Pseudomonas/imunologia , Infecções por Pseudomonas/microbiologia , Fatores de Tempo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Vacinação , Vacinas de Produtos Inativados/administração & dosagem
12.
Anal Chem ; 93(40): 13426-13433, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34585907

RESUMO

Klebsiella pneumoniae (K. pneumoniae) is one of the most aggressive multidrug-resistant bacteria associated with human infections, resulting in high mortality and morbidity. We obtained 1190 K. pneumoniae isolates from different patients with urinary tract infections. The isolates were measured to determine their susceptibility regarding nine specific antibiotics. This study's primary goal is to evaluate the potential of infrared spectroscopy in tandem with machine learning to assess the susceptibility of K. pneumoniae within approximately 20 min following the first culture. Our results confirm that it was possible to classify the isolates into sensitive and resistant with a success rate higher than 80% for the tested antibiotics. These results prove the promising potential of infrared spectroscopy as a powerful method for a K. pneumoniae susceptibility test.


Assuntos
Infecções por Klebsiella , Klebsiella pneumoniae , Antibacterianos/farmacologia , Humanos , Infecções por Klebsiella/tratamento farmacológico , Testes de Sensibilidade Microbiana , Microscopia
13.
Front Cell Infect Microbiol ; 11: 684704, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34485172

RESUMO

Phage therapy is one of the most promising alternatives to antibiotics as we face global antibiotic resistance crisis. However, the pharmacokinetics (PK) and pharmacodynamics (PD) of phage therapy are largely unknown. In the present study, we aimed to evaluate the PK/PD of a locally isolated virulent novel øKp_Pokalde_002 (Podoviridae, C1 morphotype) that infects carbapenem-resistant Klebsiella pneumoniae (Kp56) using oral and intraperitoneal (IP) route in a mouse model. The result showed that the øKp_Pokalde_002 rapidly distributed into the systemic circulation within an hour via both oral and IP routes. A higher concentration of phage in plasma was found after 4 h (2.3 x 105 PFU/ml) and 8 h (7.3 x 104 PFU/ml) of administration through IP and oral route, respectively. The phage titer significantly decreased in the blood and other tissues, liver, kidneys, and spleen after 24 h and completely cleared after 72 h of administration. In the Kp56 infection model, the bacterial count significantly decreased in the blood and other organs by 4-7 log10 CFU/ml after 24 h of øKp_Pokalde_002 administration. Elimination half-life of øKp_Pokalde_002 was relatively shorter in the presence of host-bacteria Kp56 compared to phage only, suggesting rapid clearance of phage in the presence of susceptible host. Further, administration of the øKp_Pokalde_002 alone in healthy mice (via IP or oral) did not stimulate pro-inflammatory cytokines (TNF-α and IL-6). Also, treatment with øKp_Pokalde_002 resulted in a significant reduction of pro-inflammatory cytokines (TNF-α and IL-6) caused by bacterial infection, thereby reducing the tissue inflammation. In conclusion, the øKp_Pokalde_002 possess good PK/PD properties and can be considered as a potent therapeutic candidate for future phage therapy in carbapenem-resistant K. pneumoniae infections.


Assuntos
Bacteriófagos , Infecções por Klebsiella , Terapia por Fagos , Animais , Klebsiella , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae , Camundongos
14.
Nat Commun ; 12(1): 5400, 2021 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-34518546

RESUMO

OqxB is an RND (Resistance-Nodulation-Division) efflux pump that has emerged as a factor contributing to the antibiotic resistance in Klebsiella pneumoniae. OqxB underwent horizontal gene transfer and is now seen in other Gram-negative bacterial pathogens including Escherichia coli, Enterobacter cloacae and Salmonella spp., further disseminating multi-drug resistance. In this study, we describe crystal structure of OqxB with n-dodecyl-ß-D-maltoside (DDM) molecules bound in its substrate-binding pocket, at 1.85 Å resolution. We utilize this structure in computational studies to predict the key amino acids contributing to the efflux of fluoroquinolones by OqxB, distinct from analogous residues in related transporters AcrB and MexB. Finally, our complementation assays with mutated OqxB and minimum inhibitory concentration (MIC) experiments with clinical isolates of E. coli provide further evidence that the predicted structural features are indeed involved in ciprofloxacin efflux.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla/genética , Klebsiella pneumoniae/genética , Proteínas de Membrana Transportadoras/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Sítios de Ligação/genética , Cristalografia por Raios X , Klebsiella pneumoniae/metabolismo , Proteínas de Membrana Transportadoras/química , Proteínas de Membrana Transportadoras/metabolismo , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ligação Proteica , Conformação Proteica , Multimerização Proteica , Relação Estrutura-Atividade
15.
Int J Mol Sci ; 22(17)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34502111

RESUMO

BACKGROUND: Klebsiella pneumoniae causes severe diseases including sepsis, pneumonia and wound infections and is differentiated into hypervirulent (hvKp) and classic (cKp) pathotypes. hvKp isolates are characterized clinically by invasive and multiple site infection and phenotypically in particular through hypermucoviscosity and increased siderophore production, enabled by the presence of the respective virulence genes, which are partly carried on plasmids. METHODS: Here, we analyzed two K. pneumoniae isolates of a human patient that caused severe multiple site infection. By applying both genomic and phenotypic experiments and combining basic science with clinical approaches, we aimed at characterizing the clinical background as well as the two isolates in-depth. This also included bioinformatics analysis of a chromosomal virulence plasmid integration event. RESULTS: Our genomic analysis revealed that the two isolates were clonal and belonged to sequence type 420, which is not only the first description of this K. pneumoniae subtype in Germany but also suggests belonging to the hvKp pathotype. The latter was supported by the clinical appearance and our phenotypic findings revealing increased siderophore production and hypermucoviscosity similar to an archetypical, hypervirulent K. pneumoniae strain. In addition, our in-depth bioinformatics analysis suggested the insertion of a hypervirulence plasmid in the bacterial chromosome, mediated by a new IS5 family sub-group IS903 insertion sequence designated ISKpn74. CONCLUSION: Our study contributes not only to the understanding of hvKp and the association between hypervirulence and clinical outcomes but reveals the chromosomal integration of a virulence plasmid, which might lead to tremendous public health implications.


Assuntos
Cromossomos Bacterianos/genética , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/genética , Plasmídeos/genética , Idoso , Humanos , Infecções por Klebsiella/patologia , Klebsiella pneumoniae/isolamento & purificação , Klebsiella pneumoniae/metabolismo , Klebsiella pneumoniae/patogenicidade , Masculino , Recombinação Genética , Sideróforos/metabolismo , Virulência/genética
17.
An Acad Bras Cienc ; 93(suppl 3): e20201559, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34586180

RESUMO

Guava (Psidium guajava L.), is adapted to tropical and subtropical climates, and, in addition to its nutritional value, has great medicinal potential. One of the medicinal effects is antibacterial, and this can be identified from the phytochemicals present in its various parts, especially the leaf, which contains flavonoids, phenols, and tannins, as well as phytocomposites with antibacterial action. Therefore, the interaction of this plant with arbuscular mycorrhizal fungi and Meloidogyne enterolobii is a biotechnological resource that can increase the production of secondary metabolites so that the guava ethanolic extract is effective against multidrug-resistant bacterial strains. Therefore, the objective of this study was to test the inhibitory action of mycorrhizal guava leaf extract and Meloidogyne enterolobii on strains of Klebsiella pneumoniae carbapenemase. Guava seedlings from cuttings were inoculated with Acaulospora longula, and later with Meloidogyne enterolobii; the leaves were harvested at two maturation times of the plant and placed in an oven. Next, a leaf extract was prepared using ethanol as a solvent. The extract was tested in multidrug-resistant strains of K. pneumoniae carbapenemase from operative wounds using disc diffusion methodology. The plant-AMF-phytonematode interaction positively potentialize the inhibitory action of guava leaf ethanolic extract on multidrug-resistant bacterial strains.


Assuntos
Anti-Infecciosos , Micorrizas , Psidium , Tylenchoidea , Animais , Antibacterianos/farmacologia , Fungos , Klebsiella pneumoniae , Extratos Vegetais/farmacologia , Folhas de Planta
18.
Medicine (Baltimore) ; 100(36): e27186, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34516520

RESUMO

ABSTRACT: The emergence of carbapenem-resistant Enterobacteriaceae made the treatment difficult, which has become a significant issue of public health. A sharp increase of carbapenem-resistance rate in Klebsiella pneumoniae was observed in a maternity and child health care hospital in Zunyi, China, in 2014.In 2015 to 2016, carbapenem-resistant Klebsiella pneumoniae (CRKp) isolated from all the clinical samples were analyzed to identify the carbapenem-resistance genes. They were then fingerprinted in order to determine their genetic relationship. Clinical data such as usage of imipenem in 2012 to 2016 and the nosocomial infection surveillance data were analyzed.Thirty-five isolates of CRKp out of 4328 various pathogens were obtained, and blaNDM-1 was identified to be the most common resistant gene present in the CRKp isolates. The fingerprint analysis identified 15 major clusters of CRKp isolates. The bacteria with close proximity relationship tended to be from the same wards. However, a few CRKp isolates from different wards were found to be genetically highly related. The clinical data showed a significantly higher usage of carbapenems in 2012 to 2013 before the CRKp rate sharply increased in 2014. The nosocomial infection surveillance showed an unexpectedly high rate of failures to meet the requirement of the hospital environment hygiene and hand hygiene in the neonatal ward.The increasing isolation rate of CRKp was associated with poorly regulated usage of carbapenems, impropriate medical practices, and the poor hospital environmental hygiene and hand hygiene.


Assuntos
Antibacterianos/uso terapêutico , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Infecção Hospitalar/epidemiologia , Farmacorresistência Bacteriana , Imipenem/uso terapêutico , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/isolamento & purificação , Adulto , Antibacterianos/farmacologia , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Criança , Pré-Escolar , China/epidemiologia , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/microbiologia , Feminino , Humanos , Imipenem/farmacologia , Lactente , Recém-Nascido , Controle de Infecções , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Masculino , Serviços de Saúde Materno-Infantil , Gravidez
19.
Emerg Infect Dis ; 27(10): 2628-2637, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34545787

RESUMO

Carbapenemase-producing Enterobacterales (CPE) bacteria are a critical global health concern; New Delhi metallo-ß-lactamase (NDM) enzymes account for >25% of all CPE found in Switzerland. We characterized NDM-positive CPE submitted to the Swiss National Reference Center for Emerging Antibiotic Resistance during a 2-year period (January 2019-December 2020) phenotypically and by using whole-genome sequencing. Most isolates were either Klebsiella pneumoniae (59/141) or Escherichia coli (52/141), and >50% were obtained from screening swabs. Among the 108 sequenced isolates, NDM-1 was the most prevalent variant, occurring in 56 isolates, mostly K. pneumoniae (34/56); the next most prevalent was NDM-5, which occurred in 49 isolates, mostly E. coli (40/49). Fourteen isolates coproduced a second carbapenemase, predominantly an OXA-48-like enzyme, and almost one third of isolates produced a 16S rRNA methylase conferring panresistance to aminoglycosides. We identified successful plasmids and global lineages as major factors contributing to the increasing prevalence of NDMs in Switzerland.


Assuntos
Escherichia coli , Klebsiella pneumoniae , Escherichia coli/enzimologia , Escherichia coli/genética , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S , Suíça/epidemiologia , beta-Lactamases
20.
Int J Mol Sci ; 22(16)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34445438

RESUMO

Gram-negative bacteria release Outer Membrane Vesicles (OMVs) into the extracellular environment. Recent studies recognized these vesicles as vectors to horizontal gene transfer; however, the parameters that mediate OMVs transfer within bacterial communities remain unclear. The present study highlights for the first time the transfer of plasmids containing resistance genes via OMVs derived from Klebsiella pneumoniae (K. pneumoniae). This mechanism confers DNA protection, it is plasmid copy number dependent with a ratio of 3.6 times among high copy number plasmid (pGR) versus low copy number plasmid (PRM), and the transformation efficiency was 3.6 times greater. Therefore, the DNA amount in the vesicular lumen and the efficacy of horizontal gene transfer was strictly dependent on the identity of the plasmid. Moreover, the role of K. pneumoniae-OMVs in interspecies transfer was described. The transfer ability was not related to the phylogenetic characteristics between the donor and the recipient species. K. pneumoniae-OMVs transferred plasmid to Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa and Burkholderia cepacia. These findings address the pivotal role of K. pneumoniae-OMVs as vectors for antimicrobial resistance genes spread, contributing to the development of antibiotic resistance in the microbial communities.


Assuntos
Vesículas Citoplasmáticas/genética , Transferência Genética Horizontal , Klebsiella pneumoniae/genética , Plasmídeos/genética , Antibacterianos/farmacologia , Proteínas de Bactérias , Farmacorresistência Bacteriana , Dosagem de Genes , Klebsiella pneumoniae/classificação , Klebsiella pneumoniae/efeitos dos fármacos , Filogenia
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