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2. Community-acquired bacterial meningitis in adults: in-hospital prognosis, long-term disability and determinants of outcome in a multicentre prospective cohort

Author

Duval, Xavier, Hoen, Bruno, Mourvillier, Bruno, Ploy, Marie-Cécile, Tubiana, Sarah, Varon, Emmanuelle, Caron, François, Bollaert, Pierre-Edouard, Gaillot, Olivier, Taha, Muhamed-Kheir, Poyart, Claire, Bonacorsi, Stephane, Vandenesch, François, Cambau, Emmanuelle, Lecuit, Marc, Gravet, Alain, Frachet, Bruno, Broucker, Thomas De, Levy Bruhl, Daniel, Raffi, François, Anguel, Nadia, Argaud, Laurent, Arista, Sophie, Armand-Lefevre, Laurence, Balavoine, Stéphanie, Baraduc, Régine, Barnaud, Guilène, Beraud, Guillaume, Bernard, Louis, Bernars, Georges, Bertei, Dominique, Bessede, Emilie, Billard Pomares, Typhaine, Biron, Charlotte, Bland, Stéphane, Boileau, Julien, Boubeau, Patrice, Bourdon, Sandra, Bousquet, Aurore, Boyer, Sophie, Bozorg-Grayeli, Alexis, Bret, Laurent, Bretonniere, Cédric, Bricaire, François, Brocas, Elsa, Brun, Michel, Buret, Jennifer, Burucoa, Christophe, Cabalion, Jean, Cabon, Mathieu, Camuset, Guillaume, Canevet, Christophe, Carricajo, Anne, Castan, Bernard, Caumes, Eric, Cazanave, Charles, Chabrol, Amélie, Challan-Belval, Thibaut, Chanteperdrix-Marillier, Vanessa, Chaplain, Chantal, Charlier-Woerther, Caroline, Chaussade, Hélène, Chirouze, Catherine, Clair, Bernard, Colot, Julien, Conil, Jean-Marie, Cordel, Hugues, Cormier, Philippe, Cousson, Joël, Cronier, Pierrick, Cua, Eric, Dao-Dubremetz, Anne, Dargere, Sylvie, Degand, Nicolas, Dekeyser, Sophie, Delaune, Deborah, Denes, Eric, Dequin, Pierre-Francois, Descamps, Diane, Descloux, Elodie, Desmaretz, Jean-Luc, Diehl, Jean-Luc, Dimet, Jérôme, Dinh, Aurélien, Escaut, Lelia, Fabe, Claude, Faibis, Frédéric, Flateau, Clara, Fonsale, Nathalie, Forestier, Emmanuel, Fortineau, Nicolas, Gagneux-Brunon, Amandine, Garandeau, Garcia, Magali, Garot, Denis, Gaudry, Stéphane, Goehringer, François, Gregoire-Faucher, Valérie, Grosset, Marine, Gubavu, Camélia, Gueit, Isabelle, Guelon, Dominique, Guimard, Thomas, Guinard, Jérôme, Hadou, Tahar, Helene, Jean-Pierre, Henard, Sandrine, Henry, Benoit, Hochart, Anne-Cécile, Illes, Gabriela, Jaffuel, Sylvain, Jarrin, Irène, Jaureguy, Françoise, Joseph, Cédric, Juvin, Marie-Emmanuelle, Kayal, Samer, Lacassin, Flore, Lamaury, Isabelle, Lanotte, Philippe, Laurens, Etienne, Laurichesse, Henri, Le Brun, Cécile, Le Moing, Vincent, Le Turnier, Paul, Lecuyer, Hervé, Ledru, Sylvie, Legrix, Céline, Lemaignen, Adrien, Lemble, Chantal, Lemee, Ludovic, Lesens, Olivier, Levast, Marion, Lhommet, Claire, Males, Silvija, Malpote, Edith, Martin-Blondel, Guillaume, Marx, Matthieu, Masson, Raphael, Matray, Olivier, Mbadi, Aurore, Mechai, Frédéric, Mellon, Guillaume, Merens, Audrey, Meyohas, Marie Caroline, Michon, Adrien, Mootien Yoganaden, Joy, Morquin, David, Mouly, Stéphane, Mrozek, Natacha, Nguyen, Sophie, Nguyen, Yohan, Ogielska, Maja, Oziol, Eric, Page, Bernard, Patrat-Delon, Solène, Patry, Isabelle, Pechinot, André, Picot, Sandrine, Pierrejean, Piroth, Lionel, Plassart, Claire, Plessis, Patrice, Portel, Laurent, Poubeau, Patrice, Poupard, Marie, Prazuck, Thierry, Quaesaet, Luc, Ramanantsoa, Adriatsiferana, Rapp, Christophe, Raskine, Laurent, Raymond, Josette, Revest, Matthieu, Riche, Agnès, Robaday-Voisin, Stéphanie, Robin, Frédéric, Romaszko, Jean-Pierre, Rousseau, Florence, Roux, Anne-Laure, Royer, Cecile, Saada, Matthieu, Salmon, Dominique, Saroufim, Carlo, Schmit, Jean-Luc, Sebire, Manuela, Segonds, Christine, Sivadon-Tardy, Valérie, Soismier, Nathalie, Kerneis, Solen, Son, Olivia, Sunder, Simon, Suy, Florence, Tande, Didier, Tankovic, Jacques, Valin, Nadia, Van Grunderbeeck, Nicolas, Verdon, Renaud, Vergnaud, Michel, Vernet-Garnier, Véronique, Vidal, Magali, Vitrat, Virginie, Vittecoq, Daniel, Vuotto, Fanny, Coordination and statistical analyses, Gorenne, Isabelle, Laouenan, Cédric, Marcault, Estelle, Mentre, France, Pasquet, Blandine, Roy, Carine, Tubiana, S., Varon, E., Biron, C., Ploy, M.-C., Mourvillier, B., Taha, M.-K., Revest, M., Poyart, C., Martin-Blondel, G., Lecuit, M., Cua, E., Pasquet, B., Preau, M., Hoen, B., and Duval, X.

Published
2020
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7. Campylobacter fetus bacteremia complicated by multiple splenic abscesses and multivisceral signs in a renal transplant recipient: a case report and review of the literature

Author

Coustillères,François, Hanoy,Mélanie, Lemée,Ludovic, Le Roy,Frank, and Bertrand,Dominique

Subjects
Transplantation, Campylobacter fetus, Bacteremia, Splenic abscess
Abstract

We report a rare case of Campylobacter fetus bacteremia in a 50-year-old woman following kidney transplantation. Bacteremia was complicated by multivisceral signs such as multiple splenic abscesses, bacterial hepatitis, erythema nodosum and reactive arthritis. Despite a prolonged diagnostic delay, the diagnosis was made on blood culture identification and the global outcome was favorable with adequate antibiotherapy. Reports in the literature describe a high rate of mortality for Campylobacter spp. septicemia, with most patients being immunocompromised. However, Campylobacter spp. has been rarely described in renal transplant patients. Moreover, a splenic septic localization due to Campylobacter spp. has been reported only once to our knowledge. Clinicians should be aware of the diagnostic difficulties related to the frequent negativity of stool samples in C. fetus septicemia, in order to implement a tailored medical strategy. Some data suggest that rapid introduction of adapted antibiotic therapy is associated with a reduction in mortality.

Published
2022

8. From tailor-made to ready-to-wear meningococcal B vaccines: longitudinal study of a clonal meningococcal B outbreak

Author

Caron, François, du Châtelet, Isabelle Parent, Leroy, Jean-Philippe, Ruckly, Corinne, Blanchard, Myriam, Bohic, Nicole, Massy, Nathalie, Morer, Isabelle, Floret, Daniel, Delbos, Valérie, Hong, Eva, Révillion, Martin, Berthelot, Gilles, Lemée, Ludovic, Deghmane, Ala-Eddine, Bénichou, Jacques, Lévy-Bruhl, Daniel, and Taha, Muhamed-Kheir

Published
2011
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9. Evolution of Bordetella pertussis over a 23-year period in France, 1996 to 2018

Author

Bouchez, Valérie, Guillot, Sophie, Landier, Annie, Armatys, Nathalie, Matczak, Soraya, Toubiana, Julie, Brisse, Sylvain, Brieu, Nathalie, Hamdad, Farida, Kempf, Marie, Pailhoriès, Hélène, Jensen, Cécile, Lehours, Philippe, Guiraud, Jennifer, Le Bars, Hervé, Isnard, Christophe, Wilhelm, Nathalie, Le Coustumier, Alain, Delmas, Julien, De Briel, Dominique, Souply, Laurent, Aberrane, Saïd, Coudé, Marie, Garnier, Fabien, Descours, Ghislaine, Jean-Pierre, Hélène, Alauzet, Corentine, Gibaud, Sophie-Anne, Bonacorsi, Stéphane, Brasme, Lucien, Lemée, Ludovic, Koebel, Christelle, Lanotte, Philippe, Bland, Stéphane, Petitprez, Hélène, Raffenot, Didier, Levast, Marion, Doucet-Populaire, Florence, Bourgeois-Nicolaos, Nadège, Burucoa, Christophe, Grattard, Florence, Marque-Juillet, Stéphanie, Biodiversité et Epidémiologie des Bactéries pathogènes - Biodiversity and Epidemiology of Bacterial Pathogens, Institut Pasteur [Paris], Centre national de Référence de la Coqueluche et autres Bordetelloses - National Reference Center for Whooping Cough and other Bordetella infections (CNR), Collège doctoral [Sorbonne universités], Sorbonne Université (SU), Département de Pédiatrie et maladies infectieuses [CHU Necker], CHU Necker - Enfants Malades [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Université de Paris (UP), This work was performed with the financial support of the Institut Pasteur and of Santé Publique France., French pertussis microbiology study group: Nathalie Brieu, Farida Hamdad, Marie Kempf, Hélène Pailhoriès, Cécile Jensen, Philippe Lehours, Jennifer Guiraud, Hervé Le Bars, Christophe Isnard, Nathalie Wilhelm, Alain Le Coustumier, Julien Delmas, Dominique De Briel, Laurent Souply, Saïd Aberrane, Marie Coudé, Fabien Garnier, Ghislaine Descours, Hélène Jean-Pierre, Corentine Alauzet, Sophie-Anne Gibaud, Stéphane Bonacorsi, Lucien Brasme, Ludovic Lemée, Christelle Koebel, Philippe Lanotte, Stéphane Bland, Hélène Petitprez, Didier Raffenot, Marion Levast, Florence Doucet-Populaire, Nadège Bourgeois-Nicolaos, Christophe Burucoa, Florence Grattard, Stéphanie Marque-Juillet, Institut Pasteur [Paris] (IP)-Université Paris Cité (UPCité), Collège Doctoral, Université Paris Cité (UPCité), and Institut Pasteur [Paris]-Institut Pasteur [Paris]

Subjects
Serotype, Bordetella pertussis, population evolution, Whooping Cough, Epidemiology, [SDV]Life Sciences [q-bio], Fimbria, MESH: Pertussis Toxin, MESH: Virulence Factors, Bordetella, Pertussis toxin, Microbiology, pertactin, MESH: Bordetella pertussis, 03 medical and health sciences, 0302 clinical medicine, Antigen, Virology, MESH: Child, medicine, Humans, Virulence Factors, Bordetella, 030212 general & internal medicine, Child, Whooping cough, 030304 developmental biology, Pertussis Vaccine, vaccine antigen deficiency, 0303 health sciences, Surveillance, MESH: Humans, biology, MESH: Bacterial Outer Membrane Proteins, Public Health, Environmental and Occupational Health, MESH: Whooping Cough, biology.organism_classification, medicine.disease, fimbriae serotype, 3. Good health, respiratory tract diseases, Vaccination, MESH: France, Pertussis Toxin, MESH: Pertussis Vaccine, France, Pertactin, Bacterial Outer Membrane Proteins
Abstract

Background Bordetella pertussis is the main agent of whooping cough. Vaccination with acellular pertussis vaccines has been largely implemented in high-income countries. These vaccines contain 1 to 5 antigens: pertussis toxin (PT), filamentous haemagglutinin (FHA), pertactin (PRN) and/or fimbrial proteins (FIM2 and FIM3). Monitoring the emergence of B. pertussis isolates that might partially escape vaccine-induced immunity is an essential component of public health strategies to control whooping cough. Aim We aimed to investigate temporal trends of fimbriae serotypes and vaccine antigen-expression in B. pertussis over a 23-year period in France (1996–2018). Methods Isolates (n = 2,280) were collected through hospital surveillance, capturing one third of hospitalised paediatric pertussis cases. We assayed PT, FHA and PRN production by Western blot (n = 1,428) and fimbriae production by serotyping (n = 1,058). Molecular events underlying antigen deficiency were investigated by genomic sequencing. Results The proportion of PRN-deficient B. pertussis isolates has increased steadily from 0% (0/38) in 2003 to 48.4% (31/64) in 2018 (chi-squared test for trend, p 481 insertion within the prn gene or a 22 kb genomic inversion involving the prn promoter sequence, indicative of convergent evolution. FIM2-expressing isolates have emerged since 2011 at the expense of FIM3. Conclusions B. pertussis is evolving through the rapid increase of PRN-deficient isolates and a recent shift from FIM3 to FIM2 expression. Excluding PRN, the loss of vaccine antigen expression by circulating B. pertussis isolates is epidemiologically insignificant.

Published
2021

16. Presence of respiratory viruses in ICU patients with community acquired-pneumonia (CAP): a one-year restrospective single center study

Author

Giry, Marion, Misset, Benoit, Boyer, Déborah, Baron, Adeline, Lemée, Ludovic, Plantier, Jean-Christophe, Gueudin, Marie, Mzembaba, Sandy, Service de soins intensifs [CHU Rouen], CHU Rouen, Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Département de microbiologie [CHU Rouen], Laboratoire de virologie [Rouen], Groupe de Recherche sur l'Adaptation Microbienne (GRAM 2.0), Université de Rouen Normandie (UNIROUEN), and Normandie Université (NU)-Normandie Université (NU)-Université de Caen Normandie (UNICAEN)

Subjects
[SDV.MP.VIR] Life Sciences [q-bio]/Microbiology and Parasitology/Virology, [SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, [SDV.MP.VIR]Life Sciences [q-bio]/Microbiology and Parasitology/Virology, [SDV.MP.BAC] Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology, [SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology, [SDV.MP] Life Sciences [q-bio]/Microbiology and Parasitology, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2018

19. Identification des Pseudomonas sp. par spectrométrie de masse type MALDI-TOF

Author

Tournus, Céline, Lemée, Ludovic, Nouvellon, Michèle, Pestel-Caron, Martine, Mzembaba, Sandy, Département de microbiologie [CHU Rouen], CHU Rouen, Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), and Normandie Université (NU)

Subjects
[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, [SDV.MP] Life Sciences [q-bio]/Microbiology and Parasitology, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2016

21. Diversité au sein du clone hypervirulent 'normand' de Neisseria meningitidis B:14:P1.7,16/ST32 : des souches plus virulentes que d'autres ?

Author

Sevestre, Julien, Pestel-Caron, Martine, Lemée, Ludovic, Caron, François, Taha, Muhamed-Kheir, Groupe de Recherche sur l'Adaptation Microbienne (GRAM 2.0), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université de Caen Normandie (UNICAEN), Normandie Université (NU), CHU Rouen, Infections Bactériennes Invasives, and Institut Pasteur [Paris]

Subjects
[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, [SDV.MHEP.MI]Life Sciences [q-bio]/Human health and pathology/Infectious diseases, [SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology, ComputingMilieux_MISCELLANEOUS, [SDV.MHEP]Life Sciences [q-bio]/Human health and pathology
Abstract

International audience

Published
2015

23. Life-Threatening Pneumopathy and U urealyticum in a STAT3-Deficient Hyper-IgE Syndrome Patient.

Author

Deverrlère, Guillaume, Lemée, Ludovic, Grangé, Steven, Boyer, Sophie, Picard, Capucine, Fischer, Alain, and Marguet, Christophe

Subjects
*AIDS diagnosis, *ANTIBIOTICS, *CELLULAR signal transduction, *GRAM-negative bacterial diseases, *COMORBIDITY, *ADOLESCENCE, DRUG therapy for AIDS
Abstract

A deficiency in signal responsible for autosomal dominant hyperimmunoglobulin E syndrome, an immunodeficiency syndrome causing Staphylococcus aureus, Streptococcus pneumonia, Haemophilus influenzae, and, rarely, Pseudomonas aeruginosa and Aspergillus sp infections. Currently, intracellular pathogens are not targeted in the management of severe infections. The pathophysiologic mechanism of hyperimmunoglobulin E syndrome immunodeficiency has recently been linked to a disorder in the T helper 17 pathway and disruption of the interleukin -23/interleukin-17 axis. We report an unusual case of severe pleuropneumopathy by Ureaplasma urealyticum in a teenage girl with STAT3-deficient hyperimmunoglobulin E syndrome (STAT3 HIES). A previous case of severe lung infection by Mycoplasma pneumoniae has already been described in a STAT3-deficient patient, but U urealyticum has never been reported in patients with STAT3 HIES. After a review of the literature, it seems that the specific immunodeficiency pathway of STAT3 HIES exposes STAT3 HIES patients to Ureaplasma lung infections because the pathophysiology of STAT3 HIES and Ureaplasma is based on STAT3 and T helper 17 cells. [ABSTRACT FROM AUTHOR]

Published
2017
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33. Multi-Virulence-Locus Sequence Typing of Staphylococcus lugdunensisGenerates Results Consistent with a Clonal Population Structure and Is Reliable for Epidemiological Typing

Author

Didi, Jennifer, Lemée, Ludovic, Gibert, Laure, Pons, Jean-Louis, and Pestel-Caron, Martine

Abstract

ABSTRACTStaphylococcus lugdunensisis an emergent virulent coagulase-negative staphylococcus responsible for severe infections similar to those caused by Staphylococcus aureus. To understand its potentially pathogenic capacity and have further detailed knowledge of the molecular traits of this organism, 93 isolates from various geographic origins were analyzed by multi-virulence-locus sequence typing (MVLST), targeting seven known or putative virulence-associated loci (atlLR2, atlLR3, hlb, isdJ, SLUG_09050, SLUG_16930, and vwbl). The polymorphisms of the putative virulence-associated loci were moderate and comparable to those of the housekeeping genes analyzed by multilocus sequence typing (MLST). However, the MVLST scheme generated 43 virulence types (VTs) compared to 20 sequence types (STs) based on MLST, indicating that MVLST was significantly more discriminating (Simpson's index [D], 0.943). No hypervirulent lineage or cluster specific to carriage strains was defined. The results of multilocus sequence analysis of known and putative virulence-associated loci are consistent with a clonal population structure for S. lugdunensis, suggesting a coevolution of these genes with housekeeping genes. Indeed, the nonsynonymous to synonymous evolutionary substitutions (dN/dS) ratio, the Tajima's D test, and Single-likelihood ancestor counting (SLAC) analysis suggest that all virulence-associated loci were under negative selection, even atlLR2(AtlL protein) and SLUG_16930 (FbpA homologue), for which the dN/dSratios were higher. In addition, this analysis of virulence-associated loci allowed us to propose a trilocus sequence typing scheme based on the intragenic regions of atlLR3, isdJ, and SLUG_16930, which is more discriminant than MLST for studying short-term epidemiology and further characterizing the lineages of the rare but highly pathogenic S. lugdunensis.

Published
2014
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34. Multilocus Sequence Typing Analysis of Staphylococcus lugdunensisImplies a Clonal Population Structure

Author

Chassain, Benoît, Lemée, Ludovic, Didi, Jennifer, Thiberge, Jean-Michel, Brisse, Sylvain, Pons, Jean-Louis, and Pestel-Caron, Martine

Abstract

ABSTRACTStaphylococcus lugdunensisis recognized as one of the major pathogenic species within the genus Staphylococcus, even though it belongs to the coagulase-negative group. A multilocus sequence typing (MLST) scheme was developed to study the genetic relationships and population structure of 87 S. lugdunensisisolates from various clinical and geographic sources by DNA sequence analysis of seven housekeeping genes (aroE, dat, ddl, gmk, ldh, recA, and yqiL). The number of alleles ranged from four (gmkand ldh) to nine (yqiL). Allelic profiles allowed the definition of 20 different sequence types (STs) and five clonal complexes. The 20 STs lacked correlation with geographic source. Isolates recovered from hematogenic infections (blood or osteoarticular isolates) or from skin and soft tissue infections did not cluster in separate lineages. Penicillin-resistant isolates clustered mainly in one clonal complex, unlike glycopeptide-tolerant isolates, which did not constitute a distinct subpopulation within S. lugdunensis. Phylogenies from the sequences of the seven individual housekeeping genes were congruent, indicating a predominantly mutational evolution of these genes. Quantitative analysis of the linkages between alleles from the seven loci revealed a significant linkage disequilibrium, thus confirming a clonal population structure for S. lugdunensis. This first MLST scheme for S. lugdunensisprovides a new tool for investigating the macroepidemiology and phylogeny of this unusually virulent coagulase-negative Staphylococcus.

Published
2012
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35. Proficiency of PCR in hospital settings for nonculture diagnosis of invasive meningococcal infections.

Author

Hong E, Barraud O, Bidet P, Bingen E, Blondiaux N, Bonacorsi S, Burucoa C, Carrer A, Fortineau N, Couetdic G, Courcol R, Garnier F, Hery-Arnaud G, Lanotte P, Le Bars H, Legrand-Quillien MC, Lemée L, Mereghetti L, Millardet C, Minet J, Plouzeau-Jayle C, Pons JL, Schneider J, and Taha MK

Subjects
France, Haemophilus influenzae genetics, Haemophilus influenzae isolation & purification, Humans, Neisseria meningitidis genetics, Sensitivity and Specificity, Streptococcus pneumoniae genetics, Streptococcus pneumoniae isolation & purification, Meningitis, Meningococcal diagnosis, Neisseria meningitidis isolation & purification, Polymerase Chain Reaction methods
Abstract

Background: Meningococcal meningitis requires rapid diagnosis and immediate management which is enhanced by the use of PCR for the ascertainment of these infections. However, its use is still restricted to reference laboratories., Methods: We conducted an inter-laboratory study to assess the implementation and the performance of PCR in ten French hospital settings in 2010., Results: Our data are in favour of this implementation. Although good performance was obtained in identifying Neisseria meningitidis positive samples, the main issue was reported in identifying other species (Streptococcus pneumoniae and Haemophilus influenzae) which are also involved in bacterial meningitis cases., Conclusions: Several recommendations are required and, mainly, PCR should target the major etiological agents (N. meningitidis, S. pneumonia, and H. influenzae) of acute bacterial meningitis. Moreover, PCR should predict the most frequent serogroups of Neisseria meningitidis according to local epidemiology.

Published
2012

36. Multilocus sequence typing for Clostridium difficile.

Author

Lemée L and Pons JL

Subjects
Phylogeny, Sequence Analysis, DNA, Bacterial Typing Techniques methods, Clostridioides difficile classification, Clostridioides difficile genetics
Abstract

Multilocus sequence typing (MLST), a nucleotide sequence-based characterization of allelic polymorphism of housekeeping genes, has been proposed as a new approach for population and evolutionary genetics and global epidemiology of bacterial pathogens. MLST provides unambiguous sequence data that can be generated from various laboratories and should be shared in a common web database. Here are presented most of materials, methods, and programs or software necessary to perform MLST on Clostridium difficile.We also describe an example of an MLST scheme for C. difficile based on sequence analysis of six housekeeping gene loci and use a set of 74 C. difficile isolates from various hosts, geographic sources, and PCR-toxigenic types (A+B+, A-B+, and A-B-). Thirty-two "sequence types" (ST) are defined from the combination of allelic data, which correlate well with toxigenic types. The estimation of linkage disequilibrium between loci reveals a clonal population structure. Mutational evolution of C. difficile is characterized, with point mutation generating new alleles at a frequency eightfold higher than recombinational exchange. Phylogenetic analysis shows that human and animal isolates do not cluster in distinct lineages, and that no hypervirulent lineage can be characterized within the population of toxigenic human isolates studied (strains from pseudomembranous colitis and antibiotic-associated diarrhea do not cluster in distinct lineages). However, all A-B+ variant isolates belong to a divergent but very homogeneous lineage in the population studied.An MLST database specific for this species is now hosted at the web site of the Institut Pasteur Paris. Since MLST data reflect evolutionary genetics of the species, they could be used as typing markers, possibly in combination with virulence genes data, for long-term global epidemiology of C. difficile.

Published
2010
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