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1.
Galicia clin ; 84(1): 42-43, Jan-Mar 2023. ilus
Artigo em Espanhol | IBECS | ID: ibc-221291

RESUMO

Se presenta el caso de un varón de 33 años que ingresó por otomastoiditis complicada tras manipulación quirúrgica con aislamiento de Corynebacterium amycolatum, un microorganismo que está cobrando interés por su papel como patógeno en los últimos años. El interés del caso radica en lo infrecuente del mismo, ya que no se han descrito en la literatura revisada casos de otomastoiditis por esta bacteria. En el caso se describe cómo se llegó al diagnóstico y el manejo que se realizó, así como una revisión de la literatura publicada hasta el momento de infecciones por C. amycolatum. Consideramos de interés el caso, así como la revisión realizada, ya que es una entidad poco conocida y revisada previamente, por lo que este documento puede aportar información sobre la misma. (AU)


Assuntos
Humanos , Masculino , Adulto , Corynebacterium/química , Corynebacterium/patogenicidade , Mastoidite/complicações , Mastoidite/tratamento farmacológico , Mastoidite/cirurgia
2.
Infect Genet Evol ; 93: 104928, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34022437

RESUMO

Non-diphtherial Corynebacterium species or diphtheroids were previously considered as the mere contaminants of clinical samples. Of late, they have been reckoned as the formidable infection causing agents of various diseases. While the scientific database is filled with articles that document whole genome analysis of individual isolates, a comprehensive comparative genomic analysis of diphtheroids alongside Corynebacterium diphtheriae is expected to enable us in understanding their genomic as well as evolutionary divergence. Here, we have analysed the whole genome sequences of forty strains that were selected from a range of eleven Corynebacterium species (pathogenic and non-pathogenic). A statistical analysis of the pan and core genomes revealed that even though the core genome is saturated, the pan genome is yet open rendering scope for newer gene families to be accumulated in the course of evolution that might further change the pathogenic behavior of these species. Every strain had bacteriophage components integrated in its genome and some of them were intact and consisted of toxins. The presence of diversified genomic islands was observed across the dataset and most of them consisted of genes for virulence and multidrug resistance. Moreover, the phylogenetic analysis showed that a diphtheroid is the last common ancestor of all the Corynebacterium species. The current study is a compilation of genomic features of pathogenic as well as non-pathogenic Corynebacterium species which provides insights into their virulence potential in the times to come.


Assuntos
Infecções por Corynebacterium/microbiologia , Corynebacterium/genética , Corynebacterium/patogenicidade , Genoma Bacteriano , Fatores de Virulência/genética , Corynebacterium/classificação , Humanos , Virulência
3.
Int J Mol Sci ; 22(7)2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33805570

RESUMO

Corynebacterium silvaticum is a newly identified animal pathogen of forest animals such as roe deer and wild boars. The species is closely related to the emerging human pathogen Corynebacterium ulcerans and the widely distributed animal pathogen Corynebacterium pseudotuberculosis. In this study, Corynebacterium silvaticum strain W25 was characterized with respect to its interaction with human cell lines. Microscopy, measurement of transepithelial electric resistance and cytotoxicity assays revealed detrimental effects of C. silvaticum to different human epithelial cell lines and to an invertebrate animal model, Galleria mellonella larvae, comparable to diphtheria toxin-secreting C. ulcerans. Furthermore, the results obtained may indicate a considerable zoonotic potential of this newly identified species.


Assuntos
Corynebacterium/patogenicidade , Células Epiteliais/microbiologia , Animais , Linhagem Celular , Chlorocebus aethiops , Corynebacterium/genética , Corynebacterium/isolamento & purificação , Infecções por Corynebacterium/microbiologia , Impedância Elétrica , Proteínas de Fluorescência Verde/genética , Células HeLa/microbiologia , Interações Hospedeiro-Patógeno , Humanos , Larva/microbiologia , Lepidópteros/microbiologia , Receptor 2 Toll-Like/metabolismo , Células Vero/microbiologia , Virulência
4.
Surg Today ; 51(11): 1813-1818, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33907898

RESUMO

PURPOSE: Clinically relevant postoperative pancreatic fistulas (CR-POPF) occurring after distal pancreatectomy often cause intra-abdominal infections. We monitored the presence of bacterial contamination in the ascitic fluid after distal pancreatectomy to clarify the bacterial origin of intra-abdominal infections associated with CR-POPF. METHODS: In 176 patients who underwent distal pancreatectomy, ascitic fluid bacterial cultures were performed on postoperative days (POD) 1-4 and when the drainage fluid became turbid. The association between postoperative ascitic bacterial contamination and CR-POPF incidence was investigated. RESULTS: CR-POPF occurred in 18 cases (10.2%). Among the patients with CR-POPF, bacterial contamination was detected in 0% on POD 1, in 38.9% on POD 4, and in 72.2% on the day (median, day 9.5) when the drainage fluid became turbid. A univariate analysis revealed a significant difference in ascitic bacterial contamination on POD 4 (p < 0.001) and amylase level on POD 3-4 (p < 0.001). A multivariate analysis revealed the amylase level and ascitic bacterial contamination on POD 4 to be independent risk factors. CONCLUSIONS: In the CR-POPF group, ascitic bacterial contamination was not observed in the early postoperative stage, but the bacterial contamination rate increased after pancreatic juice leakage occurred. Therefore, CR-POPF-related infections in distal pancreatectomy may be caused by a retrograde infection of pancreatic juice.


Assuntos
Líquido Ascítico/microbiologia , Infecções Bacterianas/microbiologia , Pancreatectomia/efeitos adversos , Pancreatectomia/métodos , Fístula Pancreática/microbiologia , Complicações Pós-Operatórias/microbiologia , Infecção da Ferida Cirúrgica/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Amilases/metabolismo , Líquido Ascítico/enzimologia , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/etiologia , Corynebacterium/isolamento & purificação , Corynebacterium/patogenicidade , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fístula Pancreática/epidemiologia , Fístula Pancreática/etiologia , Suco Pancreático/microbiologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Pseudomonas/isolamento & purificação , Pseudomonas/patogenicidade , Fatores de Risco , Staphylococcus/isolamento & purificação , Staphylococcus/patogenicidade , Streptococcus/isolamento & purificação , Streptococcus/patogenicidade , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Fatores de Tempo
5.
Arch Microbiol ; 203(5): 1863-1880, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33625540

RESUMO

Corynebacterium striatum is part of microbiota of skin and nasal mucosa of humans and has been increasingly reported as the etiologic agent of community-acquired and nosocomial diseases. Antimicrobial multidrug-resistant (MDR) C. striatum strains have been increasingly related to various nosocomial diseases and/or outbreaks worldwide, including fatal invasive infections in immunosuppressed and immunocompetent patients. Although cases of infections by C. striatum still neglected in some countries, the improvement of microbiological techniques and studies led to the increase of survival of patients with C. striatum nosocomial infections at different levels of magnitude. Biofilm formation on abiotic surfaces contributes for the persistence of virulent C. striatum and dissemination of antimicrobial resistance in hospital environment. Besides that, empirical antibiotic therapy can select multi-resistant strains and transfer intra and interspecies genes horizontally. In this study, a worldwide survey of C. striatum human infections and nosocomial outbreaks was accomplished by the analysis of clinical-epidemiological and microbiological features of reported cases from varied countries, during a 44-year period (1976-2020).


Assuntos
Antibacterianos/farmacologia , Infecções por Corynebacterium/microbiologia , Corynebacterium/patogenicidade , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana Múltipla , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Corynebacterium/efeitos dos fármacos , Infecções por Corynebacterium/epidemiologia , Infecção Hospitalar/epidemiologia , Surtos de Doenças/estatística & dados numéricos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Humanos , Virulência
6.
BMC Infect Dis ; 20(1): 389, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32487026

RESUMO

BACKGROUND: Intracranial infections with Corynebacterium striatum (C. striatum) have been described sporadically in the literature over the last two decades. However, C. striatum meningitis combined with multiple abscesses has not been published before. CASE PRESENTATION: In this report, we describe the clinical and imaging findings in a 54-year-old woman with meningitis caused by C. striatum and combined with suspected brain and lung abscesses. This patient who underwent multiple fractures and a recent cut presented with headache and paraphasia. C. striatum was isolated in cerebrospinal fluid and supposedly transmitted from the skin purulent wound through blood. The patient was treated with intravenous vancomycin and had a transient improvement, but died finally. Multiple abscesses, especially in the brain, could be a reason to explain her conditions were deteriorating rapidly. CONCLUSIONS: Note that C. striatum can cause life-threatening infections. Early identification and diagnosis, early administration of antibiotics to which the bacterium is susceptible, and treatment of complications will be beneficial in patients with C. striatum-related infection.


Assuntos
Abscesso Encefálico/microbiologia , Infecções por Corynebacterium/complicações , Abscesso Pulmonar/microbiologia , Meningites Bacterianas/microbiologia , Antibacterianos/uso terapêutico , Abscesso Encefálico/diagnóstico por imagem , Abscesso Encefálico/tratamento farmacológico , Líquido Cefalorraquidiano/microbiologia , Corynebacterium/isolamento & purificação , Corynebacterium/patogenicidade , Infecções por Corynebacterium/tratamento farmacológico , Feminino , Humanos , Traumatismos da Perna/microbiologia , Abscesso Pulmonar/diagnóstico por imagem , Abscesso Pulmonar/tratamento farmacológico , Meningites Bacterianas/complicações , Meningites Bacterianas/tratamento farmacológico , Pessoa de Meia-Idade , Vancomicina/uso terapêutico
7.
Antonie Van Leeuwenhoek ; 113(8): 1225-1239, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32500295

RESUMO

The genus Corynebacterium includes species of biotechnological, medical and veterinary importance. An atypical C. ulcerans strain, W25, was recently isolated from a case of necrotizing lymphadenitis in a wild boar. In this study, we have analysed the genome sequence of this strain and compared the phenotypic and virulence properties with other corynebacterial pathogens. Phylogenomic analyses revealed that strain W25 belongs to a novel species along with PO100/5 and KL1196. The latter strains were isolated from a pig and a roe deer, respectively; hence, this species appears to be associated to animals. The isolate W25 is likely a non-toxigenic tox gene bearing strain and may have compromised abilities to adhere to pharyngeal and laryngeal epithelial cells due to potential loss of the gene functions in spaBC and spaDEF pilus gene clusters. A number of corynebacterial virulence genes are present including pld encoding phospholipase D. Therefore, this strain may be able to cause severe invasive infections in animals and zoonotic infections in humans.


Assuntos
Infecções por Corynebacterium/microbiologia , Infecções por Corynebacterium/veterinária , Corynebacterium/classificação , Corynebacterium/isolamento & purificação , Filogenia , Animais , Toxinas Bacterianas/genética , Corynebacterium/genética , Corynebacterium/patogenicidade , Cervos , Fímbrias Bacterianas/genética , Genoma Bacteriano , Humanos , Família Multigênica , Suínos , Virulência/genética , Fatores de Virulência/genética , Zoonoses/microbiologia
8.
Eur J Clin Microbiol Infect Dis ; 39(9): 1745-1752, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32367215

RESUMO

Despite constituting part of the human commensal flora, Corynebacterium pseudodiphtheriticum has been recognized as a potentially infectious agent, most frequently in immunocompromised patients or individuals with other morbidity factors, but significant association to comorbid states remains unproven. This study's purpose was to assess clinical significance, risk factors for infection and antimicrobial susceptibility of C. pseudodiphtheriticum isolates. A retrospective observational study was conducted. Relevance of isolation was determined by clinical, laboratory, and imaging criteria. Forty-nine isolates occurred in 47 episodes. Colonization was assumed in 12% and infection in 78%, of which 51% were nosocomial. Patients with infection were older, with male predominance; both age and gender were statistically significant (p < 0.05) between infection and colonization groups. Although dyslipidemia (58%), arterial hypertension (58%), invasive procedures (56%), and chronic lung disease (50%) were prevalent in the infection group, no comorbidity was a significant risk factor for infection compared with colonization. Charlson comorbidity index showed no statistically difference between groups. Mortality rate was 14% in infection. Respiratory samples were the main isolation product; all tested strains were susceptible to amoxicillin/clavulanate and vancomycin. Resistant strains were observed for clindamycin (77%) and erythromycin (48%). C. pseudodiphtheriticum isolation was associated with infection in most cases. Despite the high prevalence of comorbidities and invasive procedures, no factors other than age and gender were significantly associated with infection. Although C. pseudodiphtheriticum may constitute a contaminant or colonizer in clinical samples, positive cultures in patients with signs and symptoms consistent with infection should not be neglected.


Assuntos
Infecções por Corynebacterium/epidemiologia , Corynebacterium/patogenicidade , Infecções Respiratórias/epidemiologia , Fatores Etários , Idoso , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Corynebacterium/efeitos dos fármacos , Infecções por Corynebacterium/tratamento farmacológico , Infecções por Corynebacterium/microbiologia , Resistência Microbiana a Medicamentos , Feminino , Hospitais Universitários , Humanos , Masculino , Testes de Sensibilidade Microbiana , Portugal/epidemiologia , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/microbiologia , Estudos Retrospectivos , Fatores Sexuais
9.
Respir Investig ; 58(3): 131-133, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32184071

RESUMO

Recent advances using molecular methods, matrix-assisted laser desorption ionization time of flightmass spectrometry, and next-generation sequencers enable rapid and precise detection of bacterial species in the clinical samples, revealing bacterial diversities in the human body. Corynebacterium species are Gram-positive bacilli, which can cause pneumonia and have been reported as causative pathogens of lower respiratory tract infections since the 1970's. However, Corynebacterium spp. may be recognized and sorted as part of normal respiratory flora on Gram staining and culture, resulting in clinical under-recognition as pathogenic bacteria. The results of the clone library method using bacterial 16S ribosomal RNA gene sequence analysis in Japanese patients with hospital-acquired pneumonia revealed that bronchoalveolar lavage fluid obtained from the lung lesions contained 11.8% Corynebacterium spp., which was the second most predominant bacterial phylotype. Additionally, among patients in whom Corynebacterium spp. were detected, C. simulans was most commonly detected followed by C. striatum. In addition, almost half of the patients in whom C. simulans was detected was monophylotypic infection and/or co-detection of C. simulansand C. striatum. Further clinical information is expected on corynebacteria as pathogens of lower respiratory tract infection.


Assuntos
Corynebacterium/patogenicidade , Pneumonia Bacteriana/microbiologia , Corynebacterium/isolamento & purificação , Humanos , Pneumonia Bacteriana/genética , RNA Ribossômico 16S , Análise de Sequência/métodos
10.
Rio de Janeiro; s.n; 2020. 194 p. graf, ilus, tab.
Tese em Português | LILACS | ID: biblio-1425433

RESUMO

Estudo descritivo retrospectivo realizado no Instituto Nacional do Câncer José Alencar Gomes da Silva, HCI-Rio de Janeiro, Brasil, (INCA-HCI-RJ), no qual foram avaliadas infecções relacionadas aos acessos venosos para tratamento oncológico, nos setores Onco-Hematológicos pediátricos. A infecção representa uma importante complicação em pacientes oncológicos em tratamento. Devido ao tratamento oncológico que envolve: procedimentos cirúrgicos muitas vezes mutilantes, tratamento com quimioterápicos que ocasionam períodos de imunossupressão e neutropenia, e tratamento radioterápico com radiação e lise celular. O uso de dispositivos venosos associados a períodos de imunossupressão pode levar a infecção da corrente sanguínea e outras complicações (por exemplo trombose). No presente estudo foram investigados aspectos clínico-epidemiológicos das infecções e da susceptibilidade antimicrobiana em amostras clínicas obtidas de processos infecciosos associados ao uso de cateteres venosos de longa permanência no tratamento oncológico em pacientes do Hospital do Câncer José de Alencar Gomes da Silva, HCI/INCA, Rio de Janeiro Brasil. Foram avaliadas: a) prevalência das espécies diversas relacionadas aos quadros infecciosos identificados nestes pacientes oncológicos; b) prevalência de casos de complicações e outras infecções invasivas relacionadas ao uso de cateteres de longa permanência; c) perfis de susceptibilidade a antimicrobianos e ocorrência de multirresistência. O desenvolvimento deste projeto de pesquisa possibilitou a observação análise e validação da evolução dos processos envolvidos nos quadros de infecções nosocomiais em pacientes oncológicos pediátricos na prevenção de complicações que envolvem todo o sistema de saúde, além de contribuir na escolha de antimicrobianos e estratégias terapêuticas mais efetivas para o tratamento de infecções em cateteres por espécies multirresistentes de Corynebacterium.


Retrospective descriptive study conducted at the National Cancer Institute José Alencar Gomes da Silva, INCA / HCI-Rio de Janeiro, Brazil, (INCA-HCI-RJ). Infection represents an important complication in cancer patients. This group is more prone to infections due to the cancer treatment that involves: surgical procedures often mutilating, treatment with chemotherapy that cause periods of immunosuppression even with neutropenia, and radiotherapy treatment with radiation and cell lysis. The vascular devices associated with these periods can lead to bloodstream infection besides others complication as thrombosis. The number of reports of infections in hospitalized cancer patients increases morbidity and mortality rates. In the present study clinical and epidemiological aspects of infections were identified and antimicrobial susceptibility were investigated in clinical exams and samples from blood patients and venous catheter in children oncological patients at the José de Alencar Gomes da Silva, HCI / INCA, Rio de Janeiro Brazil. It was possible evaluate a) prevalence of various species infections in cancer patients; b) prevalence of cases of complications and other invasive infections related to the use of long-term catheters; c) antimicrobial susceptibility profiles and occurrence of multidrug resistance. The development of this research project in nosocomial infections in pediatric cancer patients was enabled analysis and validation of some process involved to prevent vascular complications that involve entire health system. In addition to contributing to the choice of antimicrobials and the most effective therapeutic strategies for the treatment of multi-resistant Corynebacterium sp.


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Infecção Hospitalar/prevenção & controle , Estratégias de Saúde , Controle de Infecções/história , Corynebacterium/patogenicidade , Trombose/prevenção & controle , Institutos de Câncer/legislação & jurisprudência , Terapia de Imunossupressão , Controle de Infecções/legislação & jurisprudência , Hospedeiro Imunocomprometido , Cateteres Venosos Centrais/efeitos adversos , Cateteres Venosos Centrais/história , Hematologia , Hospitais Pediátricos , Transtornos Linfoproliferativos , Neoplasias/complicações , Neutropenia/diagnóstico
11.
Nat Rev Dis Primers ; 5(1): 81, 2019 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-31804499

RESUMO

Diphtheria is a potentially fatal infection mostly caused by toxigenic Corynebacterium diphtheriae strains and occasionally by toxigenic C. ulcerans and C. pseudotuberculosis strains. Diphtheria is generally an acute respiratory infection, characterized by the formation of a pseudomembrane in the throat, but cutaneous infections are possible. Systemic effects, such as myocarditis and neuropathy, which are associated with increased fatality risk, are due to diphtheria toxin, an exotoxin produced by the pathogen that inhibits protein synthesis and causes cell death. Clinical diagnosis is confirmed by the isolation and identification of the causative Corynebacterium spp., usually by bacterial culture followed by enzymatic and toxin detection tests. Diphtheria can be treated with the timely administration of diphtheria antitoxin and antimicrobial therapy. Although effective vaccines are available, this disease has the potential to re-emerge in countries where the recommended vaccination programmes are not sustained, and increasing proportions of adults are becoming susceptible to diphtheria. Thousands of diphtheria cases are still reported annually from several countries in Asia and Africa, along with many outbreaks. Changes in the epidemiology of diphtheria have been reported worldwide. The prevalence of toxigenic Corynebacterium spp. highlights the need for proper clinical and epidemiological investigations to quickly identify and treat affected individuals, along with public health measures to prevent and contain the spread of this disease.


Assuntos
Antitoxina Diftérica/uso terapêutico , Difteria/diagnóstico , Difteria/tratamento farmacológico , Antibacterianos/uso terapêutico , Corynebacterium/efeitos dos fármacos , Corynebacterium/patogenicidade , Difteria/epidemiologia , Humanos , Vacinação/métodos
12.
Medicina (Kaunas) ; 55(10)2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31627324

RESUMO

Background and objectives: The objective of this study was to investigate the clinical significance of isolates from blood stream infection known to be blood culture contaminants in pediatric patients. Materials and Methods: Microbiological reports and medical records of all blood culture tests issued from 2002 to 2012 (n = 76,331) were retrospectively reviewed. Evaluation for potential contaminants were done by reviewing medical records of patients with the following isolates: coagulase-negative Staphylococcus, viridans group Streptococcus, Bacillus, Corynebacterium, Micrococcus, Aerococcus, and Proprionibacterium species. Repeated cultures with same isolates were considered as a single case. Cases were evaluated for their status as a pathogen. Results: Coagulase-negative Staphylococcus had clinical significance in 23.8% of all cases. Its rate of being a true pathogen was particularly high in patients with malignancy (43.7%). Viridans group Streptococcus showed clinical significance in 46.2% of all cases. Its rate of being a true pathogen was similar regardless of the underlying morbidity of the patient. The rate of being a true pathogens for remaining isolates was 27.7% for Bacillus and 19.0% for Corynebacterium species. Conclusions: Coagulase-negative Staphylococcus and viridans group Streptococcus isolates showed high probability of being true pathogens in the pediatric population, especially in patients with underlying malignancy.


Assuntos
Bacteriemia/diagnóstico , Hemocultura/normas , Pediatria/normas , Aerococcus/isolamento & purificação , Aerococcus/patogenicidade , Bacillus/isolamento & purificação , Bacillus/patogenicidade , Bacteriemia/sangue , Hemocultura/estatística & dados numéricos , Pré-Escolar , Corynebacterium/isolamento & purificação , Corynebacterium/patogenicidade , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Micrococcus/isolamento & purificação , Micrococcus/patogenicidade , Pediatria/métodos , Estudos Retrospectivos , Staphylococcus/isolamento & purificação , Staphylococcus/patogenicidade , Estreptococos Viridans/isolamento & purificação , Estreptococos Viridans/patogenicidade
13.
Vet Microbiol ; 237: 108399, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31585651

RESUMO

Corynebacterium (C.) ulcerans is a zoonotic member of the C. diphtheriae group and is known to cause abscesses in humans and several animal species. Toxigenic strains, expressing the tox gene encoding diphtheria toxin, are also able to cause diphtheria in humans. In recent years, a non-toxigenic but tox gene-bearing (NTTB) variant of C. ulcerans has been identified that was frequently isolated from clinically healthy as well as from diseased wildlife animals, especially wild boars (Sus scrofa scrofa) in Germany and Austria. The described clinical cases showed similar signs of disease and the isolated corynebacteria displayed common genetic features as well as similar spectroscopic characteristics, therefore being assigned to a so called wild boar cluster (WBC). This study describes the establishment and validation of a method using MALDI-TOF mass spectrometry for a reliable differentiation between various members of the C. diphtheriae group at species level as well as a reliable sub-level identification of C. ulcerans isolates of the WBC variant. For this study 93 C. ulcerans isolates from wildlife animals, 41 C. ulcerans isolates from other animals and humans, and 53 isolates from further representatives of the C. diphtheriae group, as well as 26 non-diphtheriae group Corynebacteria collected via the MALDI user platform from seven MALDI users were used. By assigning 86 C. ulcerans isolates to the WBC the extensive geographical distribution of this previously less noticed variant in two Central European countries could be shown.


Assuntos
Corynebacterium/genética , Corynebacterium/patogenicidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/veterinária , Sus scrofa/microbiologia , Animais , Corynebacterium/isolamento & purificação
14.
BMC Res Notes ; 12(1): 695, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31653227

RESUMO

OBJECTIVES: In frame of a study to characterize the interaction of human macrophage-like cells with pathogenic corynebacteria, Corynebacterium diphtheriae and Corynebacterium ulcerans, live cell imaging experiments were carried out and time lapse fluorescence microscopy videos were generated, which are presented here. DATA DESCRIPTION: The time lapse fluorescence microscopy data revealed new insights in the interaction of corynebacteria with human macrophage-like THP-1 cells. In contrast to uninfected cells and infections with non-pathogenic C. glutamicum used as a control, pathogenic C. diphtheriae and C. ulcerans showed highly detrimental effects towards human cells and induction of cell death of macrophages.


Assuntos
Corynebacterium diphtheriae/patogenicidade , Corynebacterium/patogenicidade , Macrófagos/microbiologia , Microscopia de Fluorescência/métodos , Imagem com Lapso de Tempo/métodos , Morte Celular/fisiologia , Corynebacterium glutamicum/fisiologia , Interações Hospedeiro-Patógeno , Humanos , Especificidade da Espécie , Células THP-1 , Virulência
15.
Comp Med ; 69(4): 276-282, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31349880

RESUMO

Modeling chronic myelomonocytic leukemia (CMML) in immunodeficient NSGS mice relies on unique human CMML specimens and consistent murine engraftment. Only anecdotal comments have thus far supported the notion that research data may be altered by Corynebacterium bovis, an opportunistic cutaneous pathogen of immunodeficient mice. C. bovis disseminated by asymptomatic and clinically affected mice with hyperkeratotic dermatitis, resulting in resilient facility contamination and infectious recurrence. Herein we report that, compared with C. bovis PCR-negative counterparts, C. bovis PCR-positive NSGS mice developed periocular and facial hyperkeratosis and alopecia and had reduced metrics indicative of ineffective human CMML engraftment, including less thrombocytopenia, less splenomegaly, fewer CMML infiltrates in histopathologic sections of murine organs, and fewer human CD45+ cells in samples from murine spleen, bone marrow, and peripheral blood that were analyzed by flow cytometry. All CMML model metrics of engraftment were significantly reduced in the C. bovis PCR-positive cohort compared with the - negative cohort. In addition, a survey of comprehensive cancer center practices revealed that most murine facilities do not routinely test for C. bovis or broadly decontaminate the facility or its equipment after a C. bovis outbreak, thus increasing the likelihood of recurrence of invalidated studies. Our findings document that CMML engraftment of NSGS mice is diminished-and the integrity of murine research data jeopardized-by C. bovis infection of immunodeficient mice. In addition, our results indicate that C. bovis should be excluded from and not tolerated in murine facilities housing immunodeficient strains.


Assuntos
Infecções por Corynebacterium/complicações , Corynebacterium/isolamento & purificação , Leucemia Mielomonocítica Crônica/complicações , Animais , Corynebacterium/patogenicidade , Infecções por Corynebacterium/diagnóstico , Infecções por Corynebacterium/imunologia , Contaminação de Equipamentos , Humanos , Leucemia Mielomonocítica Crônica/imunologia , Camundongos , Infecções Oportunistas/complicações , Infecções Oportunistas/diagnóstico , Infecções Oportunistas/imunologia , Reação em Cadeia da Polimerase
16.
Microbiology (Reading) ; 165(8): 876-890, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31162026

RESUMO

Diphtheria toxin is one of the best investigated bacterial toxins and the major virulence factor of toxigenic Corynebacterium diphtheriae and Corynebacterium ulcerans strains. However, also diphtheria toxin-free strains of these two species can cause severe infections in animals and humans, indicating the presence of additional virulence factors. In this study, we present a first characterization of two proteins with cytotoxic effect in corynebacteria. A putative ribosome-binding protein (AEG80717, CULC809_00177), first annotated in a genome sequencing project of C. ulcerans strain 809, was investigated in detail together with a homologous protein identified in C. diphtheriae strain HC04 (AEX80148, CDHC04_0155) in this study. The corresponding proteins show striking structural similarity to Shiga-like toxins. Interaction of wild-type, mutant and complementation as well as overexpression strains with invertebrate model systems and cell lines were investigated. Depending on the presence of the corresponding genes, detrimental effects were observed in vivo in two invertebrate model systems, Caenorhabditis elegans and Galleria mellonella, and on various animal and human epithelial and macrophage cell lines in vitro. Taken together, our results support the idea that pathogenicity of corynebacteria is a multifactorial process and that new virulence factors may influence the outcome of potentially fatal corynebacterial infections.


Assuntos
Corynebacterium diphtheriae/genética , Corynebacterium/genética , Citotoxinas/biossíntese , Exotoxinas/genética , Fatores de Virulência/genética , Animais , Proteínas de Bactérias/biossíntese , Corynebacterium/patogenicidade , Infecções por Corynebacterium/microbiologia , Corynebacterium diphtheriae/patogenicidade , Citotoxinas/genética , Difteria/microbiologia , Toxina Diftérica , Exotoxinas/biossíntese , Humanos , Fatores de Virulência/biossíntese
17.
Antonie Van Leeuwenhoek ; 112(9): 1331-1340, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31055716

RESUMO

Corynebacterium striatum strains have been increasingly reported as etiological agents of nosocomial infections and outbreaks in industrialized and developing countries. However, there are few studies focused on the virulence potential of C. striatum. A growing body of research supports the use of Caenorhabditis elegans as a model host for investigating the virulence potential of pathogenic bacteria, including corynebacteria. In the present study, chemotaxis behaviour, mortality, and morphological changes were investigated in nematodes infected by four C. striatum strains isolated from different clinical sites, and with different MDR profiles and PFGE types. The results showed chemotaxis of nematodes towards C. striatum. Nematode death (> 60%) was detected from the first day post-infection with all strains tested, but at different levels, independent of biofilm formation on catheter surfaces and differences in growth temperature between nematodes (20 °C) and mammals (37 °C). C. striatum 2369/II multidrug-resistant (MDR; from tracheal aspirate of a patient undergoing endotracheal intubation) and 1961/III multidrug-sensitive (MDS; urine) strains led to 100% mortality in worms. Survival of nematodes was observed until 4 days post-infection with the C. striatum 1954/IV MDS strain isolated from a surgical wound (13%) and 1987/I MDR strain isolated from a patient with a lower respiratory tract infection (39%). The Dar phenotype was observed post-infection with all MDS and MDR strains except 1954/IV. All strains showed the capacity for bagging formation. Star formation was observed only with strains that led to 100% nematode mortality. In conclusion, C. striatum was found to exert virulence for C. elegans. Variations in nematode morphological changes and levels of mortality indicate differences in the virulence potential of C. striatum independent of clinical isolation site, capacity for biofilm formation, and MDR and PFGE profiles.


Assuntos
Caenorhabditis elegans/microbiologia , Infecções por Corynebacterium/microbiologia , Infecções por Corynebacterium/patologia , Corynebacterium/crescimento & desenvolvimento , Corynebacterium/patogenicidade , Animais , Caenorhabditis elegans/fisiologia , Corynebacterium/classificação , Corynebacterium/isolamento & purificação , Modelos Animais de Doenças , Farmacorresistência Bacteriana Múltipla , Eletroforese em Gel de Campo Pulsado , Humanos , Análise de Sobrevida , Virulência
18.
Med Hypotheses ; 126: 38-41, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31010496

RESUMO

The predominance of the genus Corynebacterium in the healthy male urogenital system contributes to the resident microbiome of not only the distal urethra, but potentially the proximal urethra and urinary bladder as well. However, for certain species in this genus, pathogenic potential was described, and the salient representative is Corynebacterium glucuronolyticum (C. glucuronolyticum) implicated in cases of urethritis and prostatitis in men. Nonetheless, some still question whether C. glucuronolyticum can actually be considered pathogenic or rather just a commensal species fortuitously isolated in patients with urogenital symptoms and/or syndromes. Although pathogen/commensal dichotomy is not always clear-cut, we hypothesize that specific genetic markers may expose C. glucuronolyticum as a convincingly pathogenic Corynebacterium. More specifically, characteristic pathogenic gene constellation inherent to this species (most notably the presence of specific sortase/SpaA-type pili gene clusters, but also the augmentative role of type VII secretion system) may significantly facilitate host tissue adhesion, with subsequent suppression/evasion of the immune response and acquisition of vitally important nutrients. Consequently, these genetic markers differentiate C. glucuronolyticum from its commensal counterparts, and give this species a pathogenic facet, which can be even further influenced by the Allee effect. In this paper we also propose a specific methodological approach on how to analyze C. glucuronolyticum epithelial colonization capacity and explore inceptive host cell-pathogen interactions that manipulate host environment and immune responses. This entails moving from approaches based primarily on overall homology of primary sequences towards specific structure-function studies to precisely evaluate all stakeholders involved in pili assemblage, cell adhesion and the expression of other virulence traits. In the era of high precision medicine, the hypothesized roles of C. glucuronolyticum adhesion systems in both virulence and nutrient acquisition may also reveal promising targets for future drug developments.


Assuntos
Corynebacterium/genética , Prostatite/microbiologia , Uretra/microbiologia , Uretrite/microbiologia , Bexiga Urinária/microbiologia , Virulência , Corynebacterium/patogenicidade , Genitália Masculina/microbiologia , Genoma Bacteriano , Interações Hospedeiro-Patógeno , Humanos , Masculino , Microbiota , Modelos Biológicos , Fenótipo
19.
Eur J Clin Microbiol Infect Dis ; 38(7): 1339-1342, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31030337

RESUMO

Corynebacterium coyleae is part of the commensal microflora of the skin, urethra, mucous membranes, and genital tract. Isolates from patients with urinary tract infection (UTI) were reported, but the pathogenic potential of this species has not been defined yet. The aim of the study is to determine whether C. coyleae could be the etiological agent of UTI and to analyze its antibiotic susceptibility. Urine samples were cultured quantitatively according to accepted laboratory procedures. The identification of bacterial isolates was carried out using the Vitek MS (bioMérieux) and antibiotic susceptibility was tested using disc diffusion according to EUCAST guidelines. Between 1 January 2017 and 30 October 2018, a total of 39 C. coyleae strains were isolated. This represented 0.32% of all urine samples cultured in the laboratory during the collection period. The strains were isolated from samples obtained from 35 women and 3 men (age median for all-64 years). One female patient presented with C. coyleae in her urine twice at an interval of 21 months. In six cases of UTI, C. coyleae was isolated in monoculture. The isolates had the same resistance pattern. A total of 11 strains were obtained from cases with a clinical diagnosis of UTI. In 13 cases, the strain was cultured in a monoculture and in 28 cases with accompanying species. All strains were susceptible to vancomycin. However, resistance to ciprofloxacin was observed for 58.4% of the strains. Urine isolates of C. coyleae must be considered as contamination or normal flora in most cases (28/39, 72%). In the remaining cases, it can be considered as potential etiologic agents, mostly in women and especially in the 6 UTI cases where C. coyleae was found as the single culture-positive species. Several of these isolates demonstrate resistance to antibiotics commonly used in empiric treatment of urinary tract infections.


Assuntos
Infecções por Corynebacterium/urina , Corynebacterium/patogenicidade , Infecções Urinárias/microbiologia , Sistema Urinário/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Ciprofloxacina/uso terapêutico , Corynebacterium/efeitos dos fármacos , Corynebacterium/isolamento & purificação , Infecções por Corynebacterium/tratamento farmacológico , Farmacorresistência Bacteriana Múltipla , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Retrospectivos , Infecções Urinárias/tratamento farmacológico , Adulto Jovem
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