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Andreas Sing - One of the best experts on this subject based on the ideXlab platform.
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Toxigenic Corynebacterium Diphtheriae-Associated Genital Ulceration
Emerging infectious diseases, 2020Co-Authors: Frieder Fuchs, Andreas Sing, Derya Markert, Isabel V Wagner, Max C. Liebau, Anja Berger, Alexandra Dangel, Mario Fabri, Georg PlumAbstract:In October 2016, an adolescent boy sought care for acute genital ulceration in Cologne, Germany. We presumed a sexually transmitted infection, but initial diagnostic procedures yielded negative results. He was hospitalized because swab samples from the lesion grew toxigenic Corynebacterium Diphtheriae, leading to the diagnosis of possibly sexually transmitted cutaneous Diphtheria.
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reliable differentiation of a non toxigenic tox gene bearing corynebacterium ulcerans variant frequently isolated from game animals using maldi tof ms
Veterinary Microbiology, 2019Co-Authors: Tobias Eisenberg, Peter Kutzer, Andreas Sing, Martin Peters, Anja Berger, Heimo Lassnig, Helmut Hotzel, R Sting, Matthias ContzenAbstract:Abstract 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 n on- t oxigenic but t ox gene- b earing (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.
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NGS-based phylogeny of Diphtheria-related pathogenicity factors in different Corynebacterium spp. implies species-specific virulence transmission
BMC Microbiology, 2019Co-Authors: Alexandra Dangel, Anja Berger, Regina Konrad, Andreas SingAbstract:Background Diphtheria toxin (DT) is produced by toxigenic strains of the human pathogen Corynebacterium Diphtheriae as well as zoonotic C. ulcerans and C. pseudotuberculosis . Toxigenic strains may cause severe respiratory Diphtheria, myocarditis, neurological damage or cutaneous Diphtheria. The DT encoding tox gene is located in a mobile genomic region and tox variability between C. Diphtheriae and C. ulcerans has been postulated based on sequences of a few isolates. In contrast, species-specific sequence analysis of the Diphtheria toxin repressor gene ( dtxR ), occurring both in toxigenic and non-toxigenic Corynebacterium species, has not been done yet. We used whole genome sequencing data from 91 toxigenic and 46 non-toxigenic isolates of different pathogenic Corynebacterium species of animal or human origin to elucidate differences in extracted DT, DtxR and tox -surrounding genetic elements by a phylogenetic analysis in a large sample set. Results Sequences of both DT and DtxR, extracted from whole genome sequencing data, could be classified in four distinct, nearly species-specific clades, corresponding to C. Diphtheriae , C. pseudotuberculosis , C. ulcerans and atypical C. ulcerans from a non-toxigenic toxin gene-bearing wildlife cluster. Average amino acid similarities were above 99% for DT and DtxR within the four groups, but lower between them. For DT, subgroups below species level could be identified, correlating with different tox -comprising mobile genetic elements. In most C. Diphtheriae , tox genes were located within known prophages. In contrast, in C. ulcerans diverse tox -including mobile elements could be identified: either prophages differing from C. Diphtheriae prophages or an alternative pathogenicity island (PAI) described previously. One isolate showed a different, shorter tox -comprising putative PAI. Beyond the tox -overlapping elements, most isolates harbored a variety of additional prophages. Conclusion Our NGS data from 137 isolates indicate the existence of different genetic backgrounds of DT-mediated pathogenicity in different Corynebacterium species and evolution of once acquired pathogenicity features with the strains. Different groups of pathogenicity-related elements within C. ulcerans imply that tox transmission pathways between isolates may differ in the zoonotic species and contribute to their emerging pathogenic potential.
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corynebacterium Diphtheriae in a free roaming red fox case report and historical review on Diphtheria in animals
Infection, 2016Co-Authors: Andreas Sing, Regina Konrad, Dominik M Meinel, Norman Mauder, Ingo Schwabe, Reinhard StingAbstract:Corynebacterium Diphtheriae, the classical causative agent of Diphtheria, is considered to be nearly restricted to humans. Here we report the first finding of a non-toxigenic C. Diphtheriae biovar belfanti strain in a free-roaming wild animal. The strain obtained from the subcutis and mammary gland of a dead red fox (Vulpes vulpes) was characterized by biochemical and molecular methods including MALDI-TOF and Multi Locus Sequence Typing. Since C. Diphtheriae infections of animals, usually with close contact to humans, are reported only very rarely, an intense review comprising also scientific literature from the beginning of the 20th century was performed. Besides the present case, only 11 previously reported C. Diphtheriae animal infections could be verified using current scientific criteria. Our report is the first on the isolation of C. Diphtheriae from a wildlife animal without any previous human contact. In contrast, the very few unambiguous publications on C. Diphtheriae in animals referred to livestock or pet animals with close human contact. C. Diphtheriae carriage in animals has to be considered as an exceptionally rare event.
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possible human to human transmission of toxigenic corynebacterium ulcerans
Clinical Microbiology and Infection, 2015Co-Authors: R. Konrad, Stefan Hormansdorfer, Andreas SingAbstract:Abstract Toxigenic Corynebacterium ulcerans is an emerging cause of Diphtheria. In contrast to the classical Diphtheria pathogen C. Diphtheriae, human-to-human transmission of this primarily zoonotic pathogen has not been clearly documented. Here we report on a two-person cluster suggesting an initial zoonotic and a subsequent human-to-human transmission event.
Aleksandra A Zasada - One of the best experts on this subject based on the ideXlab platform.
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changes in mlst profiles and biotypes of corynebacterium Diphtheriae isolates from the Diphtheria outbreak period to the period of invasive infections caused by nontoxigenic strains in poland 1950 2016
BMC Infectious Diseases, 2018Co-Authors: Urszula Czajka, Aldona Wiatrzyk, Ewa Mosiej, Kamila Formińska, Aleksandra A ZasadaAbstract:Corynebacterium Diphtheriae is a re-emerging pathogen in Europe causing invasive infections in vaccinated persons and classical Diphtheria in unvaccinated persons. In the presented study we analysed genetic changes in C. Diphtheriae isolates collected in Poland from the period before the introduction of the mass anti-Diphtheria vaccination to the present time when over 98% of the population is vaccinated. A total of 62 C. Diphtheriae isolates collected in the 1950s–1960s, 1990s and 2000–2016 in Poland were investigated. Examined properties of the isolates included toxigenic status, presence of tox gene, biotype, MLST type (ST) and type of infection. A total of 12 sequence types (STs) were identified among the analysed C. Diphtheriae isolates. The highest variability of STs was observed among isolates from Diphtheria and asymptomatic carriers collected in the XX century. Over 95% of isolates collected from invasive and wound infections in 2004–2016 belonged to ST8. Isolates from the XX century represented all four biotypes: mitis, gravis, intermedius and belfanti, but the belfanti biotype appeared only after the epidemic in the 1990s. All except three isolates from the XXI century represented the biotype gravis. During a Diphtheria epidemic period, non-epidemic clones of C. Diphtheriae might also disseminate and persist in a particular area after the epidemic. An increase of the anti-Diphtheria antibody level in the population causes not only the elimination of toxigenic strains from the population but may also influence the reduction of diversity of C. Diphtheriae isolates. MLST types do not reflect the virulence of isolates. Each ST can be represented by various virulent variants representing various pathogenic capacities, for example toxigenic non-invasive, nontoxigenic invasive and nontoxigenic non-invasive.
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Changes in MLST profiles and biotypes of Corynebacterium Diphtheriae isolates from the Diphtheria outbreak period to the period of invasive infections caused by nontoxigenic strains in Poland (1950–2016)
BMC Infectious Diseases, 2018Co-Authors: Urszula Czajka, Aldona Wiatrzyk, Ewa Mosiej, Kamila Formińska, Aleksandra A ZasadaAbstract:Background Corynebacterium Diphtheriae is a re-emerging pathogen in Europe causing invasive infections in vaccinated persons and classical Diphtheria in unvaccinated persons. In the presented study we analysed genetic changes in C. Diphtheriae isolates collected in Poland from the period before the introduction of the mass anti-Diphtheria vaccination to the present time when over 98% of the population is vaccinated. Methods A total of 62 C. Diphtheriae isolates collected in the 1950s–1960s, 1990s and 2000–2016 in Poland were investigated. Examined properties of the isolates included toxigenic status, presence of tox gene, biotype, MLST type (ST) and type of infection. Results A total of 12 sequence types (STs) were identified among the analysed C. Diphtheriae isolates. The highest variability of STs was observed among isolates from Diphtheria and asymptomatic carriers collected in the XX century. Over 95% of isolates collected from invasive and wound infections in 2004–2016 belonged to ST8. Isolates from the XX century represented all four biotypes: mitis, gravis, intermedius and belfanti , but the belfanti biotype appeared only after the epidemic in the 1990s. All except three isolates from the XXI century represented the biotype gravis . Conclusions During a Diphtheria epidemic period, non-epidemic clones of C. Diphtheriae might also disseminate and persist in a particular area after the epidemic. An increase of the anti-Diphtheria antibody level in the population causes not only the elimination of toxigenic strains from the population but may also influence the reduction of diversity of C. Diphtheriae isolates. MLST types do not reflect the virulence of isolates. Each ST can be represented by various virulent variants representing various pathogenic capacities, for example toxigenic non-invasive, nontoxigenic invasive and nontoxigenic non-invasive.
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Multilocus Sequence Typing Identifies Evidence for Recombination and Two Distinct Lineages of Corynebacterium Diphtheriae
Journal of Clinical Microbiology, 2010Co-Authors: F. Bolt, Pamela K Cassiday, Andreas Sing, Kathryn Bernard, Maria Lucia Tondella, Aruni Dezoysa, Androulla Efstratiou, Aleksandra A Zasada, Nicole Guiso, Edgar BadellAbstract:We describe the development of a multilocus sequence typing (MLST) scheme for Corynebacterium Diphtheriae, the causative agent of the potentially fatal upper respiratory disease Diphtheria. Global changes in Diphtheria epidemiology are highlighted by the recent epidemic in the former Soviet Union (FSU) and also by the emergence of nontoxigenic strains causing atypical disease. Although numerous techniques have been developed to characterize C. Diphtheriae, their use is hindered by limited portability and, in some instances, poor reproducibility. One hundred fifty isolates from 18 countries and encompassing a period of 50 years were analyzed by multilocus sequence typing (MLST). Strain discrimination was in accordance with previous ribotyping data, and clonal complexes associated with disease outbreaks were clearly identified by MLST. The data produced are portable, reproducible, and unambiguous. The MLST scheme described provides a valuable tool for monitoring and characterizing endemic and epidemic C. Diphtheriae strains. Furthermore, multilocus sequence analysis of the nucleotide data reveals two distinct lineages within the population of C. Diphtheriae examined, one of which is composed exclusively of biotype belfanti isolates and the other of multiple biotypes.
Anja Berger - One of the best experts on this subject based on the ideXlab platform.
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Toxigenic Corynebacterium Diphtheriae-Associated Genital Ulceration
Emerging infectious diseases, 2020Co-Authors: Frieder Fuchs, Andreas Sing, Derya Markert, Isabel V Wagner, Max C. Liebau, Anja Berger, Alexandra Dangel, Mario Fabri, Georg PlumAbstract:In October 2016, an adolescent boy sought care for acute genital ulceration in Cologne, Germany. We presumed a sexually transmitted infection, but initial diagnostic procedures yielded negative results. He was hospitalized because swab samples from the lesion grew toxigenic Corynebacterium Diphtheriae, leading to the diagnosis of possibly sexually transmitted cutaneous Diphtheria.
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reliable differentiation of a non toxigenic tox gene bearing corynebacterium ulcerans variant frequently isolated from game animals using maldi tof ms
Veterinary Microbiology, 2019Co-Authors: Tobias Eisenberg, Peter Kutzer, Andreas Sing, Martin Peters, Anja Berger, Heimo Lassnig, Helmut Hotzel, R Sting, Matthias ContzenAbstract:Abstract 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 n on- t oxigenic but t ox gene- b earing (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.
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NGS-based phylogeny of Diphtheria-related pathogenicity factors in different Corynebacterium spp. implies species-specific virulence transmission
BMC Microbiology, 2019Co-Authors: Alexandra Dangel, Anja Berger, Regina Konrad, Andreas SingAbstract:Background Diphtheria toxin (DT) is produced by toxigenic strains of the human pathogen Corynebacterium Diphtheriae as well as zoonotic C. ulcerans and C. pseudotuberculosis . Toxigenic strains may cause severe respiratory Diphtheria, myocarditis, neurological damage or cutaneous Diphtheria. The DT encoding tox gene is located in a mobile genomic region and tox variability between C. Diphtheriae and C. ulcerans has been postulated based on sequences of a few isolates. In contrast, species-specific sequence analysis of the Diphtheria toxin repressor gene ( dtxR ), occurring both in toxigenic and non-toxigenic Corynebacterium species, has not been done yet. We used whole genome sequencing data from 91 toxigenic and 46 non-toxigenic isolates of different pathogenic Corynebacterium species of animal or human origin to elucidate differences in extracted DT, DtxR and tox -surrounding genetic elements by a phylogenetic analysis in a large sample set. Results Sequences of both DT and DtxR, extracted from whole genome sequencing data, could be classified in four distinct, nearly species-specific clades, corresponding to C. Diphtheriae , C. pseudotuberculosis , C. ulcerans and atypical C. ulcerans from a non-toxigenic toxin gene-bearing wildlife cluster. Average amino acid similarities were above 99% for DT and DtxR within the four groups, but lower between them. For DT, subgroups below species level could be identified, correlating with different tox -comprising mobile genetic elements. In most C. Diphtheriae , tox genes were located within known prophages. In contrast, in C. ulcerans diverse tox -including mobile elements could be identified: either prophages differing from C. Diphtheriae prophages or an alternative pathogenicity island (PAI) described previously. One isolate showed a different, shorter tox -comprising putative PAI. Beyond the tox -overlapping elements, most isolates harbored a variety of additional prophages. Conclusion Our NGS data from 137 isolates indicate the existence of different genetic backgrounds of DT-mediated pathogenicity in different Corynebacterium species and evolution of once acquired pathogenicity features with the strains. Different groups of pathogenicity-related elements within C. ulcerans imply that tox transmission pathways between isolates may differ in the zoonotic species and contribute to their emerging pathogenic potential.
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whole genome sequencing suggests transmission of corynebacterium Diphtheriae caused cutaneous Diphtheria in two siblings germany 2018
Eurosurveillance, 2019Co-Authors: Anja Berger, Stefan Hormansdorfer, Alexandra Dangel, Regina Konrad, Tilmann Schober, Birgit Schmidbauer, Durdica Marosevic, Soren Schubert, Nikolaus Ackermann, Johannes HubnerAbstract:In September 2018, a child who had returned from Somalia to Germany presented with cutaneous Diphtheria by toxigenic Corynebacterium Diphtheriae biovar mitis. The child’s sibling had superinfected insect bites harbouring also toxigenic C. Diphtheriae. Next generation sequencing (NGS) revealed the same strain in both patients suggesting very recent human-to-human transmission. Epidemiological and NGS data suggest that the two cutaneous Diphtheria cases constitute the first outbreak by toxigenic C. Diphtheriae in Germany since the 1980s.
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rapid detection and molecular differentiation of toxigenic corynebacterium Diphtheriae and corynebacterium ulcerans strains by lightcycler pcr
Journal of Clinical Microbiology, 2011Co-Authors: Andreas Sing, Anja Berger, Wulf Schneiderbrachert, Thomas Holzmann, Udo ReischlAbstract:The systemic symptoms of Diphtheria are caused by the tox-encoded Diphtheria toxin (DT) which is produced by toxigenic Corynebacterium spp. Besides the classical agent C. Diphtheriae, the zoonotic pathogen C. ulcerans has increasingly been reported as an emerging pathogen for Diphtheria. The reliable detection of toxigenic Corynebacterium spp. is of substantial importance for both Diphtheria surveillance in the public health sector and the clinical workup of a patient with Diphtherialike symptoms. Since the respective tox genes of C. Diphtheriae and C. ulcerans differ from each other in both DNA and amino acid sequence, both tox genes should be covered by novel real-time PCR methods. We describe the development and validation of a LightCycler PCR assay which reliably recognizes tox genes from both C. Diphtheriae and C. ulcerans and differentiates the respective target genes by fluorescence resonance energy transfer (FRET) hybridization probe melting curve analysis.
Pamela K Cassiday - One of the best experts on this subject based on the ideXlab platform.
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Multilocus Sequence Typing Identifies Evidence for Recombination and Two Distinct Lineages of Corynebacterium Diphtheriae
Journal of Clinical Microbiology, 2010Co-Authors: F. Bolt, Pamela K Cassiday, Andreas Sing, Kathryn Bernard, Maria Lucia Tondella, Aruni Dezoysa, Androulla Efstratiou, Aleksandra A Zasada, Nicole Guiso, Edgar BadellAbstract:We describe the development of a multilocus sequence typing (MLST) scheme for Corynebacterium Diphtheriae, the causative agent of the potentially fatal upper respiratory disease Diphtheria. Global changes in Diphtheria epidemiology are highlighted by the recent epidemic in the former Soviet Union (FSU) and also by the emergence of nontoxigenic strains causing atypical disease. Although numerous techniques have been developed to characterize C. Diphtheriae, their use is hindered by limited portability and, in some instances, poor reproducibility. One hundred fifty isolates from 18 countries and encompassing a period of 50 years were analyzed by multilocus sequence typing (MLST). Strain discrimination was in accordance with previous ribotyping data, and clonal complexes associated with disease outbreaks were clearly identified by MLST. The data produced are portable, reproducible, and unambiguous. The MLST scheme described provides a valuable tool for monitoring and characterizing endemic and epidemic C. Diphtheriae strains. Furthermore, multilocus sequence analysis of the nucleotide data reveals two distinct lineages within the population of C. Diphtheriae examined, one of which is composed exclusively of biotype belfanti isolates and the other of multiple biotypes.
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analysis of toxigenic corynebacterium ulcerans strains revealing potential for false negative real time pcr results
Journal of Clinical Microbiology, 2008Co-Authors: Pamela K Cassiday, Lucia C Pawloski, Tejpratap Tiwari, Gary N. Sanden, Patricia P WilkinsAbstract:Diphtheria surveillance depends on the rapid and reliable recognition of the toxin gene in Corynebacterium Diphtheriae. Real-time PCR is a rapid tool to confirm the presence of the Diphtheria toxin gene (tox) in an isolate or specimen. We report that some toxigenic Corynebacterium ulcerans strains show atypical results in a real-time PCR for tox.
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development of a real time fluorescence pcr assay for rapid detection of the Diphtheria toxin gene
Journal of Clinical Microbiology, 2002Co-Authors: Elizabeth Mothershed, Pamela K Cassiday, Kevin Pierson, Leonard W Mayer, Tanja PopovicAbstract:We developed and evaluated a real-time fluorescence PCR assay for detecting the A and B subunits of Diphtheria toxin (tox) gene. When 23 toxigenic Corynebacterium Diphtheriae strains, 9 nontoxigenic C. Diphtheriae strains, and 44 strains representing the diversity of pathogens and normal respiratory flora were tested, this real-time PCR assay exhibited 100% sensitivity and specificity. It allowed for the detection of both subunits of the tox gene at 750 times greater sensitivity (2 CFU) than the standard PCR (1,500 CFU). When used directly on specimens collected from patients with clinical Diphtheria, one or both subunits of the tox gene were detected in 34 of 36 specimens by using the real-time PCR assay; only 9 specimens were found to be positive by standard PCR. Reamplification by standard PCR and DNA sequencing of the amplification product confirmed all real-time PCR tox-positive reactions. This real-time PCR format is a more sensitive and rapid alternative to standard PCR for detection of the tox gene in clinical material.
Edgar Badell - One of the best experts on this subject based on the ideXlab platform.
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corynebacterium Diphtheriae infection in mahajanga madagascar first case report
Journal of Tropical Pediatrics, 2021Co-Authors: Rivo Rakotomalala, Edgar Badell, Julie Toubiana, Zo Zafitsara Andrianirina, Elisoa Ratsima, Patrick Randrianandraina, Frederique Randrianirina, Glenn Torrencelli Edosoa, Tahirimalala RabenandrianinaAbstract:Diphtheria is an infection that has been unreported for more than two decades in Mahajanga. A child, aged 4, presented with a pseudomembranous pharyngitis was associated with a dysphagia. He was from a rural municipality of Ambato Boeny at Mahajanga province and was admitted to the Pediatric Unit of the University Hospital Center. The child was not immunized against Diphtheria. A throat swab was performed and cultured, from which Corynebacterium Diphtheriae was identified. The strain, of biovar Mitis, was confirmed as Diphtheria toxin (DT)-gene positive and produced DT (Elek test). Unfortunately, the child developed cardiac and neurological complications and died of respiratory and heart failure.
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Corynebacterium rouxii sp. nov., a novel member of the Diphtheriae species complex
Research in Microbiology, 2020Co-Authors: Edgar Badell, Melanie Hennart, Carla Rodrigues, Virginie Passet, Mélody Dazas, Valerie Bouchez, Leonardo Panunzi, Annick Carmi-leroy, Julie Toubiana, Sylvain BrisseAbstract:A group of six clinical isolates previously identified as Corynebacterium Diphtheriae biovar Belfanti, isolated from human cutaneous or peritoneum infections and from one dog, were characterized by genomic sequencing, biochemical analysis and MALDI-TOF mass spectrometry. The six isolates were negative for the Diphtheria toxin gene. Phylogenetic analyses showed that the six isolates (including FRC0190T) are clearly demarcated from C. Diphtheriae, Corynebacterium belfantii, Corynebacterium ulcerans and Corynebacterium pseudotuberculosis. The average nucleotide identity of FRC0190T with C. Diphtheriae NCTC11397T was 92.6%, and was 91.8% with C. belfantii FRC0043T. C. Diphtheriae subsp. lausannense strain CHUV2995T appeared to be a later heterotypic synonym of C. belfantii (ANI, 99.3%). Phenotyping data revealed an atypical negative or heterogeneous intermediate maltose fermentation reaction for the six isolates. MALDI-TOF mass spectrometry differentiated the new group from the other Corynebacterium taxa by the presence of specific spectral peaks. rpoB sequences showed identity to atypical, maltose-negative C. Diphtheriae biovar Belfanti isolates previously described from two cats in the USA. We propose the name Corynebacterium rouxii sp. nov. for the novel group, with FRC0190T (= CIP 111752T = DSM 110354T) as type strain.
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Re-emergence of Corynebacterium Diphtheriae
Médecine et Maladies Infectieuses, 2019Co-Authors: Carole Scheifer, Edgar Badell, Sylvain Brisse, O Patey, Camille Rolland-debord, Florence Reibel, Alexandra Aubry, Alice Pérignon, Eric CaumesAbstract:BACKGROUND: Diphtheria is re-emerging in Europe. A total of 36 cases were reported in Europe in 2015 versus 53 cases between 2000 and 2009. PATIENTS: We report two cases of Corynebacterium Diphtheriae infection in a French hospital in 2016: a cutaneous infection with negative toxin testing in a French traveller, and a respiratory Diphtheria carriage with positive toxin testing in an Afghan refugee diagnosed with pulmonary tuberculosis. The vaccination history of the Afghan patient could not be retrieved.
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new Diphtheria toxin repressor types depicted in a romanian collection of corynebacterium Diphtheriae isolates
Journal of Basic Microbiology, 2014Co-Authors: Sorin Dinu, Nicole Guiso, Edgar Badell, Maria Damian, Cristiana Cerasella DragomirescuAbstract:Corynebacterium Diphtheriae is the etiological agent of Diphtheria, a potential fatal disease caused by a corynephage toxin. The expression of this Diphtheria toxin is controlled via an iron-dependent repressor with various functions (DtxR). Some mutations in the dtxR gene are associated with diminished activity or even with total loss of DtxR function. We conducted a molecular study to characterize the dtxR alleles harbored by 34 isolates of C. Diphtheriae recovered from Romanian patients between 1961 and 2007. Three of the seven alleles identified in this study have not previously been described. Two new DtxR types were identified, one of which has an unusual polypeptide length. All the new DtxR types were found in toxigenic isolates, suggesting that they effectively regulate the expression of Diphtheria toxin. Furthermore, one of the new DtxR identified was also found in a non-toxigenic isolate, making it a potential source of toxigenic isolates after lysogenic conversion.
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microbiological changes and diversity in autochthonous non toxigenic corynebacterium Diphtheriae isolated in france
Clinical Microbiology and Infection, 2013Co-Authors: Nicole Guiso, Edgar Badell, E Farfour, S Dinu, Sophie GuillotAbstract:Autochtonous toxigenic Corynebacterium Diphtheriae have disappeared in mainland France, but non-toxigenic C. Diphtheriae are still circulating. Using phenotypic and molecular tools, we retrospectively characterized 103 non-toxigenic C. Diphtheriae collected in mainland France and highlight several changes. The proportion of C. Diphtheriae belfanti increased between 1977 and 2011 and it is the most frequent biotype recovered in recent years. Resistance to ciprofloxacin has increased and most isolates with decreased sensitivity belong to the belfanti biotype. Using multilocus sequence typing, we demonstrate that French isolates are distributed in a large number of sequence types and identify three distinct lineages. C. Diphtheriae mitis and gravis form lineage I while C. Diphtheriae belfanti forms lineages II and III. Almost all isolates of lineage II are part of a unique clonal complex or are very close to it. Most French isolates have a dtxR sequence homologous to that of toxigenic isolates, suggesting that if lyzogenised by a corynephage, they can express Diphtheria toxin.
