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1.
Emerg Infect Dis ; 30(8): 1545-1554, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39043387

RESUMO

Human infections with Corynebacterium diphtheriae species complex (CdSC) bacteria were rare in French Guiana until 2016, when the number of cases diagnosed increased. We conducted an epidemiologic, multicenter, retrospective study of all human CdSC infections diagnosed in French Guiana during January 1, 2016-December 31, 2021. A total of 64 infectious episodes were observed in 60 patients; 61 infections were caused by C. diphtheriae and 3 by C. ulcerans. Estimated incidence increased from 0.7 cases/100,000 population in 2016 to 7.7 cases/100,000 population in 2021. The mean patient age was 30.4 (+23.7) years, and male-to-female ratio was 1.7:1 (38/22). Of the 61 C. diphtheriae isolates, 5 tested positive for the diphtheria toxin gene, and all results were negative by Elek test; 95% (61/64) of cases were cutaneous, including the C. ulcerans cases. The increase in reported human infections underscores the need to raise awareness among frontline healthcare practitioners to improve prevention.


Assuntos
Corynebacterium diphtheriae , Difteria , Humanos , Guiana Francesa/epidemiologia , Estudos Retrospectivos , Feminino , Masculino , Corynebacterium diphtheriae/isolamento & purificação , Corynebacterium diphtheriae/genética , Adulto , Pessoa de Meia-Idade , Adolescente , Criança , Adulto Jovem , Pré-Escolar , Difteria/epidemiologia , Difteria/microbiologia , Idoso , Incidência , Lactente , História do Século XXI , Infecções por Corynebacterium/epidemiologia , Infecções por Corynebacterium/microbiologia
2.
BMC Genom Data ; 24(1): 65, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37940844

RESUMO

BACKGROUND: Corynebacterium diphtheriae complex was formed by the species C. diphtheriae, Corynebacterium ulcerans and Corynebacterium pseudotuberculosis in the recent past. In addition to C. diphtheriae, C. ulcerans and C. pseudotuberculosis species can carry the tox gene, which encodes diphtheria toxin. Currently, three new species have been included in the complex: Corynebacterium rouxii, Corynebacterium silvaticum, and Corynebacterium belfantii. C. rouxii is derived from the ancient Belfanti biovar of C. diptheriae. We provide the complete genome sequences of two non-toxigenic strains C. rouxii isolated from a cat with a purulent infection in Brazil. The taxonomic status and sequence type, as well as the presence of resistance and virulence genes, and CRISPR-Cas system were additionally defined. RESULTS: The genomes showed an average size of 2.4 Mb and 53.2% GC content, similar to the type strain of the species deposited in Genbank/NCBI. Strains were identified as C. rouxii by the rMLST database, with 95% identity. ANI and DDH in silico were consistent with values above the proposed cut-off points for species limit, corroborating the identification of the strains as C. rouxii. MLST analyses revealed a new ST, which differs from ST-537 only by the fusA allele. No horizontal transfer resistance gene was predicted in both genomes and no mutation was detected in the constitutive genes gyrA and rpoB. Some mutations were found in the seven penicillin-binding proteins (PBPs) detected. The tox gene was not found, but its regulatory gene dtxR was present. Among the predicted virulence genes are those involved in iron uptake and adherence, in addition to the DIP0733 protein involved in epithelial cell adhesion and invasion. The CRISPR-Cas type I-E system was detected in both genomes, with 16 spacer sequences each. Of them, half are unknown according to the databases used, indicating that there is an unexplored reservoir of corynebacteriophages and plasmids. CONCLUSIONS: This is the first genomic study of C. rouxii reported in Brazil. Here we performed taxonomic analysis and the prediction of virulence factors. The genomic analyses performed in this study may help to understand the potential pathogenesis of non-toxigenic C. rouxii strains.


Assuntos
Corynebacterium diphtheriae , Corynebacterium diphtheriae/genética , Filogenia , Brasil , Tipagem de Sequências Multilocus , Corynebacterium/genética
3.
Braz J Microbiol ; 54(3): 1325-1334, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37597133

RESUMO

Diphtheria is an infectious disease potentially fatal that constitutes a threat to global health security, with possible local and systemic manifestations that result mainly from the production of diphtheria toxin (DT). In the present work, we report a case of infection by Corynebacterium diphtheriae in a cutaneous lesion of a fully immunized individual and provided an analysis of the complete genome of the isolate. The clinical isolate was first identified by MALDI-TOF Mass Spectrometry. The commercial strip system and mPCR performed phenotypic and genotypic characterization, respectively. The antimicrobial susceptibility profile was determined by the disk diffusion method. Additionally, genomic DNA was sequenced and analyzed for species confirmation and sequence type (ST) determination. Detection of resistance and virulence genes was performed by comparisons against ResFinder and VFDB databases. The isolate was identified as a nontoxigenic C. diphtheriae biovar Gravis strain. Its genome presented a size of 2.46 Mbp and a G + C content of 53.5%. Ribosomal Multilocus Sequence Typing (rMLST) allowed the confirmation of species as C. diphtheriae with 100% identity. DDH in silico corroborated this identification. Moreover, MLST analyses revealed that the isolate belongs to ST-536. No resistance genes were predicted or mutations detected in antimicrobial-related genes. On the other hand, virulence genes, mostly involved in iron uptake and adherence, were found. Presently, we provided sufficient clinical data regarding the C. diphtheriae cutaneous infection in addition to the phenotypic and genomic data of the isolate. Our results indicate a possible circulation of ST-536 in Brazil, causing cutaneous infection. Considering that cases of C. diphtheriae infections, as well as diphtheria outbreaks, have still been reported in several regions of the world, studies focusing on taxonomic analyzes and predictions of resistance genes may help to improve the diagnosis and to monitor the propagation of resistant clones. In addition, they can contribute to understanding the association between variation in genetic factors and resistance to antimicrobials.


Assuntos
Corynebacterium diphtheriae , Difteria , Humanos , Corynebacterium diphtheriae/genética , Tipagem de Sequências Multilocus , Celulite (Flegmão) , Genótipo
4.
Int Wound J ; 20(3): 774-783, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36787273

RESUMO

Epidermolysis bullosa (EB) is an inherited disorder characterised by skin fragility and the appearance of blisters and wounds. Patient wounds are often colonised or infected with bacteria, leading to impaired healing, pain and high risk of death by sepsis. Little is known about the impact of bacterial composition and susceptibility in wound resolution, and there is a need for longitudinal studies to understand healing outcomes with different types of bacterial colonisation. A prospective longitudinal study of 70 wounds from 15 severe EB patients (Junctional and Recessive Dystrophic EB) from Chile. Wounds were selected independently of their infected status. Wound cultures, including bacterial species identification, composition and Staphylococcus aureus (SA) antibiotic susceptibility were registered. Wounds were separated into categories according to their healing capacity, recognising chronic, and healing wounds. Hundred-one of the 102 wound cultures were positive for bacterial growth. From these, 100 were SA-positive; 31 were resistant to Ciprofloxacin (31%) and only seven were methicillin-resistant SA (7%). Ciprofloxacin-resistant SA was found significantly predominant in chronic wounds (**P < .01). Interestingly, atoxigenic Corynebacterium diphtheriae (CD) was identified and found to be the second most abundant recovered bacteria (31/101), present almost always in combination with SA (30/31). CD was only found in Recessive Dystrophic EB patients and not related to wound chronicity. Other less frequent bacterial species found included Pseudomonas aeruginosa, Streptococus spp. and Proteus spp. Infection was negatively associated with the healing status of wounds.


Assuntos
Corynebacterium diphtheriae , Epidermólise Bolhosa Distrófica , Epidermólise Bolhosa , Infecções Estafilocócicas , Humanos , Staphylococcus aureus , Estudos Longitudinais , Estudos Prospectivos , Epidermólise Bolhosa/complicações , Infecções Estafilocócicas/tratamento farmacológico , Cicatrização , Ciprofloxacina , Epidermólise Bolhosa Distrófica/complicações
5.
Braz J Cardiovasc Surg ; 36(1): 137-139, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33594869

RESUMO

Infective endocarditis is a rather uncommon disease, but it has significant mortality rates in the pediatric population (5% to 10%). We report a case of an infant patient with multiple vegetation in the tricuspid valve secondary to infective endocarditis caused by Corynebacterium diphtheriae. A tricuspid valvuloplasty was performed with a fenestrated autologous pericardium patch, providing satisfactory outcomes. This technique is simple, innovative, effective, and it could be applied in similar cases.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Endocardite Bacteriana , Endocardite , Criança , Endocardite Bacteriana/diagnóstico por imagem , Endocardite Bacteriana/cirurgia , Humanos , Pericárdio/cirurgia , Pericárdio/transplante , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/cirurgia
6.
Rev. bras. cir. cardiovasc ; Rev. bras. cir. cardiovasc;36(1): 137-139, Jan.-Feb. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1155791

RESUMO

Abstract Infective endocarditis is a rather uncommon disease, but it has significant mortality rates in the pediatric population (5% to 10%). We report a case of an infant patient with multiple vegetation in the tricuspid valve secondary to infective endocarditis caused by Corynebacterium diphtheriae. A tricuspid valvuloplasty was performed with a fenestrated autologous pericardium patch, providing satisfactory outcomes. This technique is simple, innovative, effective, and it could be applied in similar cases.


Assuntos
Humanos , Criança , Endocardite , Endocardite Bacteriana/cirurgia , Endocardite Bacteriana/diagnóstico por imagem , Procedimentos Cirúrgicos Cardíacos , Pericárdio/cirurgia , Pericárdio/transplante , Valva Tricúspide/cirurgia , Valva Tricúspide/diagnóstico por imagem
7.
Access Microbiol ; 3(11): 000284, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35018328

RESUMO

Diphtheria is a potentially fatal infection, mostly caused by diphtheria toxin (DT)-producing Corynebacterium diphtheriae strains. During the last decades, the isolation of DT-producing C. diphtheriae strains has been decreasing worldwide. However, non-DT-producing C. diphtheriae strains emerged as causative agents of cutaneous and invasive infections. Although endemic in countries with warm climates, cutaneous diphtheria is rarely reported in Brazil. Presently, an unusual case of skin lesion in a Brazilian elderly diabetic patient infected by a penicillin-resistant non-DT-producing C. diphtheriae strain was reported. Laboratory diagnosis included mass spectrometry and multiplex PCR analyses. Since cutaneous diphtheria lesions are possible sources of secondary diphtheria cases and systemic diseases and considering that penicillin is the first line of antimicrobial agent for the treatment of these infections, the detection of penicillin-resistant strains of diphtheria bacilli should be a matter of concern. Thus, cases similar to the presently reported should be appropriately investigated and treated, particularly in patients with risk factor (s) for the development of C. diphtheriae invasive infections, such as diabetes. Moreover, health professionals must be aware of the presence of C. diphtheriae in cutaneous lesions of lower limbs, a common type of morbidity in diabetic patients, especially in tropical and subtropical countries.

8.
Br J Oral Maxillofac Surg ; 58(3): 358-360, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31864859

RESUMO

Diphtheria is an infectious disease caused by Corynebacterium diphtheriae, and is generally characterised by proliferation of the bacteria in the upper respiratory tract, formation of a pseudomembrane, and systemic diffusion of the diphtheria toxin throughout the body. We present the case of a young man with pseudomembranous plaques on the tongue and floor of the mouth, who received systemic and locoregional medical treatment, with a satisfactory outcome after 14 days.


Assuntos
Corynebacterium diphtheriae , Difteria , Humanos , Masculino , Nariz , Traqueia
9.
J Trop Pediatr ; 65(2): 183-187, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29688558

RESUMO

Infection with Corynebacterium diphtheriae persists in Haiti. Twenty-six children with clinically severe respiratory diphtheria presented to a hospital in northern Haiti during a 3-year period beginning in early 2015. The mortality rate was 50%. Partial or absent vaccinations as well as delayed and limited care contributed to mortality. This cohort offer insights into the multiple challenges involved in preventing and caring for children with diphtheria in resource-limited settings.


Assuntos
Corynebacterium diphtheriae/isolamento & purificação , Difteria/diagnóstico , Infecções Respiratórias/complicações , Infecções Respiratórias/microbiologia , Criança , Estudos de Coortes , Diagnóstico Tardio , Difteria/tratamento farmacológico , Difteria/microbiologia , Difteria/mortalidade , Antitoxina Diftérica/administração & dosagem , Feminino , Haiti/epidemiologia , Acessibilidade aos Serviços de Saúde , Humanos , Imunização , Infecções Respiratórias/epidemiologia , Vacinação
10.
Emerg Infect Dis ; 24(7): 1340-1344, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29912686

RESUMO

In February 2017, a diphtheria outbreak occurred among Amerindians of the Pemón ethnic group in Wonken, Venezuela. A field investigation revealed ≈10 cases; clinical presentation did not include cutaneous or neurologic signs or symptoms. To prevent future outbreaks in Venezuela, Amerindian communities need better access to vaccination and healthcare.


Assuntos
Corynebacterium diphtheriae , Difteria/epidemiologia , Surtos de Doenças , Adulto , Difteria/história , Difteria/microbiologia , Feminino , Geografia Médica , História do Século XXI , Humanos , Masculino , Vigilância da População , Venezuela/epidemiologia
11.
Informe Quincenal Epidemiológico Nacional (IQEN) ; 23(1-24): [11], 2018. tab, grafi, ilus
Artigo em Espanhol | COLNAL | ID: biblio-1023511

RESUMO

la difteria es una enfermedad producida por cepas toxigénicas de Corynebacterium diphtheriae. La presentación de casos está facilitada por factores como la pobreza, el hacinamiento, esquemas de vacunación incompletos o inexistentes, entre otros. El objetivo del reporte de caso es presentar el primer caso de mortalidad por difteria importado en Colombia.


Diphtheria is a disease caused by toxigenic strains of Corynebacterium diphtheriae. The presentation of cases is facilitated by factors such as poverty, overcrowding, incomplete or non-existent vaccination schemes, among others. The objective of the case report is to present the first case of mortality from diphtheria imported into Colombia.


Assuntos
Humanos , Difteria , Monitoramento Epidemiológico
12.
Vet Microbiol ; 207: 149-152, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28757016

RESUMO

Porcine Corynebacterium infection is still poorly studied, even though the pig has been described as an asymptomatic carrier of Corynebacterium species, including the zoonotic species C. ulcerans, C. confusum and C. amycolatum. Here we present the identification, molecular and antimicrobial susceptibility characterization of coryneform bacteria isolated from sows with urinary tract infection. C. diphtheriae, C. confusum and C. amycolatum were isolated from sows with urinary infection and metritis. Corynebacterium species were identified by MALDI-TOF MS and confirmed by 16S rRNA and rpoB sequencing. All porcine C. diphtheriae strains were further characterized as non-toxigenic (tox-). SE-AFLP genotyping was also performed and enabled not only Corynebacterium species differentiation but also the assessment of C. amycolatum genetic heterogeneity. All studied porcine Corynebacterium strains presented alarming resistance profiles with high MIC values for macrolides/lincosamide, tetracyclines and quinolones, which can be related with high usage in both veterinary and human medicine. Isolation of zoonotic Corynebacterium species from commercial swine is important for assessing the potential zoonotic risk for farmers and further implication for both human and animal treatment.


Assuntos
Infecções por Corynebacterium/veterinária , Corynebacterium/classificação , Doenças Urogenitais Femininas/veterinária , Doenças dos Suínos/microbiologia , Animais , Antibacterianos , Corynebacterium/genética , Corynebacterium/isolamento & purificação , Infecções por Corynebacterium/microbiologia , Farmacorresistência Bacteriana , Feminino , Doenças Urogenitais Femininas/microbiologia , Testes de Sensibilidade Microbiana , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Suínos
13.
Antonie Van Leeuwenhoek ; 108(5): 1275-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26459339

RESUMO

Corynebacterium diphtheriae strains continue to circulate worldwide causing diphtheria and invasive diseases, such as endocarditis, osteomyelitis, pneumonia and catheter-related infections. Presumptive C. diphtheriae infections diagnosis in a clinical microbiology laboratory requires a primary isolation consisting of a bacterial culture on blood agar and agar containing tellurite (TeO3(2-)). In this study, nine genome sequenced and four unsequenced strains of C. diphtheriae from different sources, including three samples from a recent outbreak in Brazil, were characterized with respect to their growth properties on tellurite-containing agar. Levels of tellurite-resistance (Te(R)) were evaluated by determining the minimum inhibitory concentrations of potassium tellurite (K2TeO3) and by a viability reduction test in solid culture medium with K2TeO3. Significant differences in Te(R) levels of C. diphtheriae strains were observed independent of origin, biovar or presence of the tox gene. Data indicated that the standard initial screening with TeO3(2-)-selective medium for diphtheria bacilli identification may lead to false-negative results in C. diphtheriae diagnosis laboratories.


Assuntos
Antibacterianos/farmacologia , Corynebacterium diphtheriae/efeitos dos fármacos , Difteria/diagnóstico , Difteria/microbiologia , Farmacorresistência Bacteriana , Telúrio/farmacologia , Proteínas de Bactérias/genética , Corynebacterium diphtheriae/classificação , Corynebacterium diphtheriae/genética , Farmacorresistência Bacteriana/genética , Humanos , Testes de Sensibilidade Microbiana , Filogenia , Fatores de Virulência/genética
14.
Mem. Inst. Oswaldo Cruz ; 110(6): 817-819, Sept. 2015. graf
Artigo em Inglês | LILACS | ID: lil-763089

RESUMO

We report the complete genome sequence and analysis of an invasive Corynebacterium diphtheriae strain that caused endocarditis in Rio de Janeiro, Brazil. It was selected for sequencing on the basis of the current relevance of nontoxigenic strains for public health. The genomic information was explored in the context of diversity, plasticity and genetic relatedness with other contemporary strains.


Assuntos
Corynebacterium diphtheriae/genética , DNA Bacteriano/genética , Genoma Bacteriano/genética , Brasil , Corynebacterium diphtheriae/classificação , Corynebacterium diphtheriae/patogenicidade , Difteria/genética , Filogenia , Virulência
15.
Mem. Inst. Oswaldo Cruz ; 110(5): 662-668, Aug. 2015. tab, ilus
Artigo em Inglês | LILACS | ID: lil-755900

RESUMO

Corynebacterium diphtheriae, the aetiologic agent of diphtheria, also represents a global medical challenge because of the existence of invasive strains as causative agents of systemic infections. Although tellurite (TeO32-) is toxic to most microorganisms, TeO32--resistant bacteria, including C. diphtheriae, exist in nature. The presence of TeO32--resistance (TeR) determinants in pathogenic bacteria might provide selective advantages in the natural environment. In the present study, we investigated the role of the putative TeR determinant (CDCE8392_813gene) in the virulence attributes of diphtheria bacilli. The disruption of CDCE8392_0813 gene expression in the LDCIC-L1 mutant increased susceptibility to TeO32- and reactive oxygen species (hydrogen peroxide), but not to other antimicrobial agents. The LDCIC-L1 mutant also showed a decrease in both the lethality of Caenorhabditis elegansand the survival inside of human epithelial cells compared to wild-type strain. Conversely, the haemagglutinating activity and adherence to and formation of biofilms on different abiotic surfaces were not regulated through the CDCE8392_0813 gene. In conclusion, the CDCE8392_813 gene contributes to the TeR and pathogenic potential of C. diphtheriae.

.


Assuntos
Animais , Humanos , Proteínas de Bactérias/fisiologia , Caenorhabditis elegans/fisiologia , Corynebacterium diphtheriae/patogenicidade , Células Epiteliais/microbiologia , Telúrio/farmacologia , Fatores de Virulência/fisiologia , Antibacterianos/farmacologia , Aderência Bacteriana , Caenorhabditis elegans/microbiologia , Corynebacterium diphtheriae/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Virulência
16.
Rev. bras. anal. clin ; 43(3): 230-236, 2011. ilus, tab
Artigo em Português | LILACS | ID: lil-651510

RESUMO

Além da difteria permanecer endêmica em diversos países, os clínicos e microbiologistas também devem permanecer atentos ao fato de amostras atoxinogênicas de Corynebacterium diphtheriae causarem infecções invasivas, inclusive em pacientesimunocomprometidos e/ou hospitalizados. Um grupo de microrganismos, incluindo C. diphtheriae, tem sido relacionado com quadros de osteomielite. Em casos de câncer, pode ser favorecido o aparecimento de quadros de osteomielite em decorrência de contaminação por via hematogênica, foco infeccioso ou lesão contígua ao osso. Entretanto, ainda são poucas as investigações relativas ao potencial patogênico de cepas atoxinogênicas de C. diphtheriae. No presente estudo, foi descrito o primeiro caso de isolamento de C.diphtheriae subsp. mitis atoxinogênico e do biotipo não fermentador de sacarose (BR5015) de osteomielite em paciente com câncer.O microrganismo foi capaz de expressar os seguintes fatores de virulência: expressão de perfil de aderência misto dos tipos agregativo e difuso (AA-AD) e elevada (11,13%) capacidade de sobrevivência intracitoplasmática em células epiteliais humanas (HEp-2) além da produção de porfirina e de enzimas catalase, nitrato redutase e DNAse. C. diphtheriae atoxinogênico não deve serconsiderado como mero contaminante, uma vez que pode estar direta ou indiretamente relacionado com o estabelecimento e/ou manutenção de processos infecciosos de origens diversas, incluindo osteomielite.


As well diphtheria remaining endemic in several countries, clinicians and microbiologists must also remain alert to the fact that nontoxigenic samples of Corynebacterium diphtheriae are capable of causing invasive infections, especially in hospitalized and/or immunocompromised patients. Patients with cancer are more susceptible to the appearance of cases of osteomyelitisobtained by hematogenic contamination, an infectious focus or by lesions adjacent to bone. Many microorganisms may be related to cases of osteomyelitis, including C. diphtheriae. However, there are still only a low number of investigations into the pathogenic potential of nontoxigenic strains of C. diphtheriae. The present study is the first documented case of isolation of a nontoxigenic C.diphtheriae subsp. mitis of the non sucrose-fermenting biotype (BR5015 strain) from osteomyelitis in the frontal bone of a patient with adenoid cystic carcinoma. The virulence factors tests were as follows: expression of a mixed adherence patterns of aggregativediffuse(AA-DA) types; high (11.13%) ability to survive within HEp-2 cells; DNase, catalase, nitrate-reductase activities. Therefore, nontoxigenic C. diphtheriae should not be merely regarded as a contaminant, since it can be directly or indirectly related to the establishment and/or maintenance of infectious processes, including osteomyelitis.


Assuntos
Humanos , Feminino , Adulto , Corynebacterium diphtheriae , Infecções por Corynebacterium , Difteria , Neoplasias , Osteomielite
17.
Mem. Inst. Oswaldo Cruz ; 105(5): 706-711, Aug. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-557234

RESUMO

The production of fibrinous exudates may play an important role in determining the outcome of bacterial infection. Although pseudomembrane formation is a characteristic feature of diphtheria, little is known about the fibrinogen (Fbn)-binding properties of Corynebacterium diphtheriae strains and the influence of the gene that codes for diphtheria toxin (tox gene) in this process. In this study we demonstrated the ability of C. diphtheriae strains to bind to Fbn and to convert Fbn to fibrin. Bacterial interaction with rabbit plasma was evaluated by both slide and tube tests. Interaction of microorganisms with human Fbn was evaluated by both enzyme linked immunosorbent assay (ELISA) and fluorescein isothiocyanate-conjugated (FITC) Fbn binding assays. Nontoxigenic and toxigenic strains formed bacterial aggregates in the presence of plasma in the slide tests. The ability to convert Fbn to a loose web of fibrin in the plasma solution in the tube tests appeared to be a common characteristic of the species, including strains that do not carry the tox gene. Fbn binding to C. diphtheriae strains occurred at varying intensities, as demonstrated by the FITC-Fbn and ELISA binding assays. Our data suggest that the capacity to bind to Fbn and to convert Fbn to fibrin may play a role in pseudomembrane formation and act as virulence determinants of both nontoxigenic and toxigenic strains.


Assuntos
Animais , Humanos , Coelhos , Corynebacterium diphtheriae , Toxina Diftérica , Fibrinogênio , Corynebacterium diphtheriae , Toxina Diftérica , Ensaio de Imunoadsorção Enzimática , Fibrinogênio , Virulência
18.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;41(11): 986-991, Nov. 2008. ilus, tab
Artigo em Inglês | LILACS | ID: lil-500362

RESUMO

Invasive diseases caused by Corynebacterium diphtheriae have been described increasingly. Several reports indicate the destructive feature of endocarditis attributable to nontoxigenic strains. However, few reports have dealt with the pathogenicity of invasive strains. The present investigation demonstrates a phenotypic trait that may be used to identify potentially invasive strains. The study also draws attention to clinical and microbiological aspects observed in 5 cases of endocarditis due to C. diphtheriae that occurred outside Europe. Four cases occurred in female school-age children (7-14 years) treated at different hospitals in Rio de Janeiro, Brazil. All patients developed other complications including septicemia, renal failure and/or arthritis. Surgical treatment was performed on 2 patients for valve replacement. Lethality was observed in 40 percent of the cases. Microorganisms isolated from 5 blood samples and identified as C. diphtheriae subsp mitis (N = 4) and C. diphtheriae subsp gravis (N = 1) displayed an aggregative adherence pattern to HEp-2 cells and identical one-dimensional SDS-PAGE protein profiles. Aggregative-adhering invasive strains of C. diphtheriae showed 5 distinct RAPD profiles. Despite the clonal diversity, all 5 C. diphtheriae invasive isolates seemed to display special bacterial adhesive properties that may favor blood-barrier disruption and systemic dissemination of bacteria. In conclusion, blood isolates from patients with endocarditis exhibited a unique adhering pattern, suggesting a pathogenic role of aggregative-adhering C. diphtheriae of different clones in endocarditis. Accordingly, the aggregative-adherence pattern may be used as an indication of some invasive potential of C. diphtheriae strains.


Assuntos
Adolescente , Criança , Feminino , Humanos , Aderência Bacteriana/fisiologia , Corynebacterium diphtheriae/patogenicidade , Endocardite Bacteriana/microbiologia , Técnicas de Tipagem Bacteriana , Células Cultivadas , Corynebacterium diphtheriae/genética , Corynebacterium diphtheriae/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Genótipo , Fenótipo , Técnica de Amplificação ao Acaso de DNA Polimórfico , Especificidade da Espécie
19.
Mem. Inst. Oswaldo Cruz ; 103(5): 507-510, Aug. 2008. tab
Artigo em Inglês | LILACS | ID: lil-491966

RESUMO

The increasing problems with multidrug resistance in relation to Corynebacterium, including C. diphtheriae, are examples of challenges confronting many countries. For this reason, Brazilian C. diphtheriae strains were evaluated by the E-Test for their susceptibility to nine antibacterial drugs used in therapy. Resistance (MIC < 0.002; 0.38 µg/ml) to penicillin G was found in 14.8 percent of the strains tested. Although erythromycin (MIC90 0.75 µg/ml) and azithromycin (MIC90 0.064 µg/ml) were active against C. diphtheriae in this study, 4.2 percent of the strains showed decreased susceptibility (MIC 1.0 µg/ml) to erythromycin. Multiple resistance profiles were determined by the disk diffusion method using 31 antibiotics. Most C. diphtheriae strains (95.74 percent) showed resistance to mupirocin, aztreonam, ceftazidime, and/or oxacillin, ampicillin, penicillin, tetracycline, clindamycin, lincomycin, and erythromycin. This study presents the antimicrobial susceptibility profiles of Brazilian C. diphtheriae isolates. The data are of value to practitioners, and suggest that some concern exists regarding the use of penicillin.


Assuntos
Antibacterianos/farmacologia , Corynebacterium diphtheriae/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Brasil , Corynebacterium diphtheriae/genética , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Fenótipo
20.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;40(12): 1681-1687, Dec. 2007. graf, tab
Artigo em Inglês | LILACS | ID: lil-466743

RESUMO

The introduction of routine vaccination against tetanus and diphtheria in Brazil has decreased the incidence and changed the epidemiology of both diseases. We then investigated the prevalence of Corynebacterium diphtheriae carrier status and diphtheria and tetanus immunity in São Paulo, Brazil. From November 2001 to March 2003, 374 individuals were tested for the presence of C. diphtheriae in the naso-oropharynx and of serum diphtheria and tetanus antibodies. Participants were all healthy individuals without acute or chronic pathologies and they were stratified by age as follows: 0-12 months and 1-4, 5-9, 10-14, 15-24, 25-39, 40-59, and ³60 years. Antibodies were assessed using a double-antigen ELISA. C. diphtheriae species were identified by biochemical analysis and toxigenicity was assessed by the Elek test. For diphtheria, full protection (antibodies ³0.1 IU/mL) was present in 84 percent of the individuals, 15 percent had basic protection (antibodies ³0.01 and <0.1 IU/mL) and 1 percent were susceptible (antibodies <0.01 IU/mL). Full tetanus protection (antibodies ³0.1 IU/mL) was present in 79 percent of the participants, 18 percent had basic protection (antibodies ³0.01 and <0.1 IU/mL) and 3 percent were susceptible (antibodies <0.01 IU/mL). The geometric mean of diphtheria and tetanus antibodies reached the highest values at 5-9 years and decreased until the 40-59-year age range, increasing again in individuals over 60 years. Three participants (0.8 percent) were carriers of C. diphtheriae, all non-toxigenic strains. The present results demonstrate the clear need of periodic booster for tetanus and diphtheria vaccine in adolescents and adults after primary immunization in childhood.


Assuntos
Adolescente , Adulto , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Anticorpos Antibacterianos/sangue , Clostridium tetani/imunologia , Corynebacterium diphtheriae/imunologia , Difteria/imunologia , Tétano/imunologia , Distribuição por Idade , Anticorpos Antibacterianos/imunologia , Brasil , Vacina contra Difteria, Tétano e Coqueluche/imunologia , Difteria/prevenção & controle , Ensaio de Imunoadsorção Enzimática , Tétano/prevenção & controle
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