Informe especial: Actualización epidemiológica de difteria / Special report: Epidemiological update of diphtheria

La difteria es una enfermedad infecciosa grave, con potencial epidémico, para la que existe una vacuna eficaz. Es una infección bacteriana aguda causada por la liberación de una exotoxina específica, producida por el bacilo gram positivo, Corynebacterium diphtheriae. Sólo las cepas toxigénicas causan enfermedad. La enfermedad se presenta principalmente en menores de 15 años de edad sin vacunación o con vacunación incompleta; no obstante puede presentarse en adultos en áreas con baja cobertura de vacunación. En este informe se presentan distintos aspectos de la enfermedad y la situación epidemiológica en las Américas y en Argentina: definiciones de caso, medidas de prevención y de control

Caso inusual de difteria cutánea con compromiso mucoso y síndrome del vértex orbitario / Unusual clinical presentation of cutaneous diphteria with mucosal involvement and orbital Vertex syndrome

La difteria es una enfermedad prevenible por vacunas. En la actualidad existe un brote en nuestro país que se inició en abril de 2016. Desde entonces se han descrito casos en diferentes sitios del país predominantemente de la forma faríngea. La difteria cutánea no ha sido reportada en este brote. A nivel mundial el compromiso simultáneo en piel y mucosas, no ha sido descrito. La paciente cuya enfermedad describimos aquí es un caso de difteria de presentación atípica que se inicia con expresión cutánea y evoluciona a compromiso nasal, ocular y faríngeo con complicaciones severas en la órbita ocular expresadas como un síndrome del vértex orbitario, en una paciente con diabetes mellitus tipo 2 no controlada, que tuvo una evolución tórpida que la llevó a la muerte. Se revisa la literatura(AU)

Diphtheria is a vaccine-preventable disease. Actually, there is an outbreak in Venezuela since April 2016. Cases in different parts of the country have been described, predominantly pharyngeal. Cutaneous diphtheria has not been reported in this outbreak. The simultaneous presentation of the cutaneous form with mucosal involvement has not been described in the revised literature. We present a case of diphtheria with atypical presentation that begins with cutaneous expression and evolves to nasal, ocular and pharyngeal compromise with severe complications of the orbit, expressed in an orbital vertex syndrome in a patient with type 2 diabetes mellitus, who had a torpid evolution that led her to death. The literature is reviewed(AU)

Genomic analysis of a nontoxigenic, invasive Corynebacterium diphtheriae strain from Brazil

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.

Corynebacterium diphtheriae putative tellurite-resistance protein (CDCE8392_0813) contributes to the intracellular survival in human epithelial cells and lethality of Caenorhabditis elegans

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 (TeO3^2-) is toxic to most microorganisms, TeO3^2--resistant bacteria, including C. diphtheriae, exist in nature. The presence of TeO3^2--resistance (Te^R) determinants in pathogenic bacteria might provide selective advantages in the natural environment. In the present study, we investigated the role of the putative Te^R 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 TeO3^2- 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 Te^R and pathogenic potential of C. diphtheriae.

Propriedades adesivas a substratos abióticos e bióticos, invasão e indução de apoptose celular de Corynebacterium pseudodiphtheriticum / Adhesive properties to abiotic and biotic substrates, invasion and induction of apoptosis of Corynebacterium pseudodiphtheriticum

A ocorrência de fenótipos multirresistentes de Corynebacterium pseudodiphtheriticum e sua associação a infecções graves, com elevada mortalidade em pacientes imunocomprometidos, aliados ao escasso conhecimento da virulência e patogenia destas infecções, motivou esta pesquisa, que teve como objetivo investigar mecanismos de virulência e resistência microbiana deste agente entre pacientes de um hospital universitário brasileiro. Um total de 113 amostras de C. pseudodiphtheriticum identificadas por métodos bioquímicos convencionais e sistema API-Coryne isoladas de pacientes de diferentes grupos etários. Os micro-organismos eram, em sua maioria, relacionados a infecções no trato respiratório (27,45%), urinário (29,20%) e sitios intravenosos (18,60%) e cerca de 32,70% das amostras foram provenientes de pacientes com pelo menos uma das condições predisponentes: insuficiência renal; transplante renal, tuberculose em paciente HIV+, câncer, cirrose hepática, hemodiálise e uso de cateter. As amostras testadas revelaram-se multirresistentes sendo a maioria resistente à oxacilina, eritromicina e clindamicina. A adesão das cepas ao poliestireno e ao poliuretano indicou o envolvimento de hidrofobicidade da superfície celular na fase inicial da formação de biofilmes. O crescimento subsequente conduziu à formação de microcolônias, agregados bacterianos densos incorporados na matriz exopolimérica rodeada por espaços vazios, típica de biofilmes maduros...

The occurrence of multiresistant phenotypes and associated with severe infections, with high mortality in immunocompromised hosts due to Corynebacterium pseudodiphtheriticum, allied to little known about virulence and pathogenesis these infections, led to present investigation. The investigation aims to examine the virulence mechanisms and resistance to antimicrobial agents of C. pseudodiphtheriticum among patients with bacterial infections at a Brazilian teaching hospital. A total of 113 C. pseudodiphtheriticum strains identified by conventional biochemical methods and API-Coryne System were recovered from patients from different age groups. Micro-organisms were mostly related to infections in the respiratory tracts (27.45%), urinary (29.20%) and intravenous sites (18.60%) and approximately 32.70% samples were obtained of patients presenting at least one of the pre-disposing conditions: end-stage renal disease; renal transplant; AIDS and Mycobacterium tuberculosis infection; cancer, hepatic cirrhosis; haemodialysis and catheter use. Antimicrobial susceptibility tests identified multiresistant phenotypes. Most strains were resistant to oxacillin, erythromycin and clindamycin. Adherence to polystyrene and polyurethane indicated the involvement of cell surface hydrophobicity in the initial stage of biofilm formation. Further growth led to the formation of dense bacterial aggregates embedded in the exopolymeric matrix surrounded by voids, typical of mature biofilms...

Papel das hemaglutininas 67-72p de Corynebacterium diphtheriae na ligação a proteínas plasmáticas, superfícies celulares, invasão e indução de apoptose / Role of haemagglutinins 67-72p de Corynebacterium diphtheriae in binding to plasma proteins, cell surfaces, invasion and induction of apoptosis

Corynebacterium diphtheriae pode ser isolado tanto de quadros de difteria clássica, quanto de infecções sistêmicas, como endocardite. O fibrinogênio (Fbn) e a fibronectina (Fn) são glicoproteínas presentes na matriz extracelular de tecidos conjuntivos. A influência destas proteínas na patogênese das infecções locais e invasivas causadas por C. diphtheriae é objeto de estudo devido ao fato do bacilo diftérico poder ser encontrado em lesões nas quais o Fbn e a Fn são predominantes, incluindo a pseudomembrana diftérica e vegetações cardíacas presentes na endocardite infecciosa. São crescentes as evidências de que o C. diphtheriae pode, além de aderir, ser internalizado por células em cultura. No presente estudo, investigou-se a participação de C. diphtheriae e das proteínas de superfície 67-72p na aderência à Fn e ao Fbn de plasma humano e a eritrócitos. A aderência às células HEp-2 e internalização também foram analisadas. A participação de 67-72p nos mecanismos de morte celular foi avaliada através das colorações por Azul de Tripan e 4'6-diamidino-2-fenil indol (DAPI), pelo ensaio de redução utilizando dimetil-tiazol-difenil tetrazólio (MTT) e por citometria de fluxo. As 67-72p foram extraídas da superfície da amostra toxigênica C. diphtheriae subsp. mitis CDC-E8392 através de processos mecânicos e precipitação com sulfato de amônio saturado. Análises por SDS-PAGE e immunoblotting detectaram a presença das bandas protéicas de 67 e 72kDa nas amostras toxinogênicas e atoxinogênicas analisadas, as quais pertenciam aos biotipos fermentador e não fermentador de sacarose. C. diphtheriae foi capaz não só de formar agregados na presença de plasma de coelho, mas também de converter Fbn em fibrina independentemente da presença do gene tox. No entanto, a amostra atoxinogênica ATCC 27010 (tox-) foi menos aderente ao Fbn do que a homóloga ATCC 27012 (tox+). A interação bacteriana com eritrócitos foi inibida somente pela Fn. Ligações entre Fn e/ou Fbn com 67-72p foram ...

Corynbacterium diphtheriae have been isolated from classical diphtheria and systemic infections such as endocarditis. Fibrinogen (Fbn) and fibronectin (Fn) are high molecular-weight glycoproteins that may be found in extracellular matrix of connective tissues. Their influence in the pathogenesis of local and in invasive C. diphtheriae infection is object of interest due to the fact that diphtheria bacilli is recovered from lesions where such proteins are predominant, including pharyngeal pseudomembrane and valve heart vegetations in infectious endocarditis. There is growing evidence that C. diphtheriae may adhere to and be internalized by cells in culture. The present study investigated the participation of C. diphtheriae strains and 67-72p, a surface protein, in adherence to human plasma Fn, Fbn, erityrocytes, adherence to and internalization by HEp-2 cells. The participation of 67-72p in promoting cell death was evaluated by the Trypan blue, DAPI staining methods, methylthiazole tetrazolium (MTT) reduction assay and flow cytometry. The 67-72p was extracted from C. diphtheriae subsp. mitis CDC-E8392 toxigenic strain, by mechanical process and ammonium sulfate fractionation. SDS-PAGE and immunoblotting analysis detected the polypeptide bands of 67 and 72 kDa in all toxigenic and nontoxigenic strains from both sucrose-fermenting and non-fermanting biotypes. Diphtheria bacilli were capable to both form bacterial aggregates in rabbit plasma and to convert Fbn to fibrin independently to the presence of tox gene, albeit the ATCC 27010 (tox-) strain was less adherent to Fbn than the paental strain ATCC 27012 (tox+). Bacteria-erythrocytes interaction was inhibited only ...

Potential pathogenic role of aggregative-adhering Corynebacterium diphtheriae of different clonal groups in endocarditis

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.

Endocarditis bacteriana causada por Corynebacterium diphtheriae biotipo gravis, no toxigénico: informe de un caso / Bacterial endocarditis caused for a non-toxigenic Corynebacterium diphtheriae, biotype gravis: Case repor

Se presenta el caso de un niño de 9 años, atendido en el Hospital Erazmo Meoz de Cúcuta, entre el 22 de noviembre de 1995 y el 18 de diciembre del mismo año, con diagnóstico de anemia, síndrome mielodisplásico y endocarditis bacteriana. En los hemocultivos, se aisló un bacilo grampositivo, identificado inicialmente como Listeria monocytogenes. El aislamiento fue enviado al Laboratorio de Referencia de Microbiología del INS para confirmación, en donde se identificó la bacteria como Corynebacterium diphtheriae, biotipo gravis, no toxigénico. No fue posible realizar el seguimiento del paciente debido a que los padres solicitaron su salida voluntaria de la institución

Difteria: o grave prognóstico brasileiro / Diphthreria: the grave Brazilian prognosis

A difteria, embora seja uma das doenças melhor estudadas atualmente, ainda ameaça a populaçao brasileira. A imunizaçao deficiente e a falta de informaçao das equipes médicas em relaçao à sua incidência dificultam o diagnóstico e o tratamento. Os autores discutem a situaçao epidemiológica brasileira e os novos métodos diagnósticos, preciosos e de baixo custo, realizados pelos laboratórios centrais de Saúde Pública.

Coagglutination for rapid testing of toxin producing Corynebacterium diphtheriae.

Coagglutination test was standardised for rapid detection of diphtheria toxin after primary culture of C. diphtheriae isolates on conventional Loeffler's medium. The procedure was optimised with diphtheria toxoid (DT)-antidiphtheritic serum (ADS) system wherein Cowan-I strain of Staphylococcus aureus was sensitised with ADS. Toxoid in the range of 1.02 lf/ml to 4200 lf/ml could be detected by the present procedure. Toxin of C. diphtheriae could be demonstrated in five of eight clinical isolates, this correlated with the conventional guinea pig pathogenicity test. The coagglutination test thus needs further confirmation of its potential as a simple and satisfactory test for rapid detection of toxin-producing C. diphtheriae.

Identificaçäo de Corybacterium diphtheriae pela técnica de imunofluorescência indireta / Identification of corynebacterium diphteriae by indirect immunofluorence technique

Os surtos de difteria, que recentemente ocorreram no território brasileiro, nos levaram a estudar diferentes testes laboratoriais, empregados no diagnóstico diferencial das amidalites. Comparamos a técnica de imunofluorescência indireta, a partir de imune-soro absorvido preparado no nosso laboratório, com a técnica direta utilizando imune-soro comercial. Demonstramos que a imunofluorescência pode ser satisfatoriamente utilizada na identificaçäo rápida do C. diphtheriae. Os microorganismos podem ser observados em esfregaços feitos de culturas puras ou mesmo naqueles obtidos com swabs de pacientes, que foram cultivados por poucas horas em meio líquido. A técnica pode também ser de grande utilidade no exama dos contactos familiares.

Efecto citopatogénico de la exotoxina diftérica en cultivos celulares de fibroblastos de embrión de pollo / Cytopathogenic effect of diphtheriae exotoxin in chicken embryo fibroblast culture

Se estudiaron 150 cepas de Corynebacterium diphtheriae obtenidas de pacientes con clínica de diftéria y de portadores sanos. De las mismas 136(90.67%) pertenecían al biotipo mitis, 12(8,00%) y 2(1,33%) a los biotipos gravis e intermedius respectivamente. Se determinó la toxigenicidad por los métodos tradicionales in vivo empleando conejos machos blancos e in vitro por la metodología de inmunodifusión en placas conteniendo medio de K.L. virulencia. de las 136 cepas del biotipo mitis, 130(95,58%) demostraron toxigenicidad positiva por ambos métodos; 11(91,66%) del biotipo gravis y las 2(100%) del biotipo intermedius igualmente dieron toxigenicidad por los métodos empleados. Se determinó también citotoxigenicidad en cultivos celulares de fibroblastos de embrión de pollo, los resultados obtenidos con esta metodología dieron citotoxicidad positiva en 132(97,05%) de las cepas agrupadas en el biotipo mitis, las 12(100%) del biotipo gravis y las 2(100%) del biotipo intermedius. Estos resultados indicaron que la citotoxicidad parece ser un método más sensible para la detección de la producción de exotoxina diftérica

Relationship of biotype and source to the hemaglutination and adhesive properties of C. Diphtheriae

A study was conducted on the hemagglutinating and adhesive properties of sucrose-fermenting and non-sucrose-fermenting Corynebacterium diphtheriae strains. Sheep erythrocytes were agglutined by 72% of tozigen C. diphtheriae strains and by 87% of nontoxigenic strains, by 67% of the strains isolated from throats and 94% of skin isolates, and by 65% of sucrose-fermenting organisms and 93% of non-sucrose-fermenting strains. Neither presence nor absence of toxin production was correlated with the hemagglutinating property. Different levels of adherence to glass surfaces occurred among C. diphtheriae strains. Strains from skin lesions and of the non-sucrose-fermenting biotype showed strong hemagglutinating activity. In contrast, sucrose-fermenting strains exhibited less hemagglutinating activity, but most of them (71%) were predominantly effective adherers to glass surfaces

Isolamento de Corynebacterium diphtheriae de líquido espermático / Isolation of Corynebacterium diphtheriae from sperm

Descrevemos o isolamento de Corynebacterium diphtheriae toxígeno de espermocultura. O microrganismo foi identificado pelo teste de fluorescência sob luz ultravioleta, pesquisa da enzima pirazina-carboxilamidase (Pyz), testes de virulência in vitro e in vivo (imunodifusäo radial simples, cultura de células e teste intradérmico em cobaio). A amostra foi inicialmente considerada atoxígena pelo teste de imunodifusäo radial simples, mas sua virulência foi observada posteriormente quando os testes acima foram aplicados. Sem adecuada especificaçäo, a amostra poderia ter sido considerada como um "difteróide"