Assessment of seven culture media for the growth and isolation of Capnocytophaga spp.

International audienc

Distribución de los genotipos de fimA en cepas de Porphyromonas gingivalis aisladas de placas subgingivales y de sangre durante bacteriemias

Introduction. Porphyromonas gingivalis is considered as a major etiological agent in the onset and progression of chronic destructive periodontitis. Porphyromonus gingivalis fimA type has been correlated to the virulence potential of the strain; therefore this gene could be involved in the ability of P. gingivalis to reach blood stream.Objective. The classifications of P. gingivalis fimA types will be compared in subgingival plaque and blood samples collected after scaling and root root planing of periodontitis patients.Materials and methods. Fifteen periodontitis patients requiring scaling and root planing were enrolled. P. gingivalis isolates were classed to genotype with fimA type-specific PCR assay. fimA gene was sequenced if the isolate was listed as unclassifiable after PCR technique.Results. Six patients showed positive P. gingivalis bacteremia. The most frequent fimA was fimA type II, followed by Ib, III and IV. In blood strains, type II was followed by IV, Ib and III.Conclusion. Type II was the most frequent genotype in blood samples and in subgingival plaque samples. However, no correlation was found between the frequency of any fimA type with SRP induced bacteremia. P. gingivalis fimA type appears to be conserved within individual patients throughout the times of sample collection. fimA gene sequence results were not in agreement with results of fimA genotyping by PCR.Introducción. Porphyromonas gingivalis es el principal agente etiológico de la periodontitis. El gen fimA ha sido relacionado con la virulencia del microorganismo, lo cual sugiere la participación de dicho gen en la capacidad del microorganismo para alcanzar el torrente sanguíneo.Objetivo. Estudiar la distribución de los tipos de fimA de P. gingivalis en muestras de placa subgingival y de sangre obtenidas durante bacteriemias después de raspaje y alisado radicular.Materiales y métodos. Se practicó un alisado radicular a 15 pacientes con periodontitis. Se obtuvieron aislamientos clínicos de P. gingivalis de la placa subgingival y durante la bacteriemia inducida por el procedimiento. Para la genotipificación se utilizó la técnica de reacción en cadena de la polimerasa (PCR) específica para fimA. En los aislamientos no clasificables por PCR se realizó secuenciación del gen fimA.Resultados. Seis pacientes fueron positivos para bacteriemia por P. gingivalis. La distribución de fimA evaluada en 30 aislamientos de placa subgingival y de sangre mostró una mayor frecuencia del fimA tipo II de P. gingivalis. En los aislamientos de placa subgingival, la detección de fimA tipo II fue seguida por Ib, III y IV; sin embargo, en los aislamientos de sangre el tipo II fue seguido por los tipos IV, Ib y III.Conclusión. En los aislamientos de sangre y de placa subgingival de pacientes con periodontitis el fimA más frecuente fue el tipo II; no fue posible correlacionar el tipo de fimA con la bacteriemia inducida por el alisado radicular. Los resultados de la secuenciación del gen fimA no concuerdan con los obtenidos por PCR

Tolerance to intraoral biofilms and their effectiveness in improving mouth dryness and modifying oral microbiota in patients with primary Sjögren’s syndrome: “Predelfi study”

IntroductionPrimary Sjögren’s syndrome (pSS) is a systemic autoimmune disease characterized by exocrine gland dysfunction. No therapeutic strategy is sufficient on its own for the management of dry mouth and therapeutic innovations are required.MethodsThis Predelfi study was a single-center, prospective, comparative, randomized, double-blind, cross-over controlled study with the primary objective of assessing the tolerance to and effectiveness of two adhesive biofilms (containing prebiotics and, sodium alginate, respectively) in patients with pSS and hyposialia (#NCT04206826 in ClinicalTrials.gov). Secondary objectives were to obtain initial data regarding the clinical effectiveness of such biofilms in the improvement of signs and symptoms related to dry mouth and potential changes in the oral microbiota. Ten pSS patients with pSS were included (9 females and 1 male) with a mean age of 58.1 ± 14.0 years.Results and discussionTolerance to the prebiotic and sodium alginate biofilms was assessed by the patients (visual analog scale [VAS] score 66.7 and 87.6, respectively) and the practitioner (90 and 100, respectively). The absolute changes in the VAS scores at the start and end of each treatment period highlighted an improvement in mouth dryness for the sodium alginate versus the prebiotic biofilm. The VAS scores for other parameters (mouth burning sensation; taste alteration; chewing; swallowing and speech difficulties) remained globally comparable between the two groups. Unstimulated salivary flow showed no changes regardless of the biofilm used. Regarding the oral microbiota, the sodium alginate biofilm increased the abundance of the Treponema genus, whereas the use of the prebiotic biofilm as the first treatment increased the abundance of the genera Veillonella and Prevotella. Nevertheless, the prebiotic biofilm appeared to stimulate “milder” genera with regard to periodontal infections. Furthermore, pre-treatment with the prebiotic biofilm prevented the emergence of the Treponema genus induced by subsequent treatment with the sodium alginate biofilm, suggesting a potential protective effect

Prevalence of oropharyngeal beta-lactamase-producing Capnocytophaga spp. in pediatric oncology patients over a ten-year period

BACKGROUND: The aim of this study was to evaluate the prevalence of beta-lactamase-producing Capnocytophaga isolates in young children hospitalized in the Pediatric Oncology Department of Hôpital Sud (Rennes, France) over a ten-year period (1993–2002). METHODS: In neutropenic children, a periodic survey of the oral cavity allows a predictive evaluation of the risk of systemic infections by Capnocytophaga spp. In 449 children with cancer, 3,053 samples were collected by oral swabbing and plated on TBBP agar. The susceptibility of Capnocytophaga isolates to five beta-lactams was determined. RESULTS: A total of 440 strains of Capnocytophaga spp. were isolated, 309 (70%) of which were beta-lactamase producers. The beta-lactamase-producing strains were all resistant to cefazolin, 86% to amoxicillin, and 63% to ceftazidime. The proportion of strains resistant to third-generation cephalosporins remained high throughout the ten-year study, while susceptibility to imipenem and amoxicillin combined with clavulanic acid was always conserved. CONCLUSION: These results highlight the risk of antibiotic failure in Capnocytophaga infections and the importance of monitoring immunosuppressed patients and testing for antibiotic susceptibility and beta-lactamase production

Porphyromonas gingivalis Participates in Pathogenesis of Human Abdominal Aortic Aneurysm by Neutrophil Activation. Proof of Concept in Rats

International audienceBACKGROUND: Abdominal Aortic Aneurysms (AAAs) represent a particular form of atherothrombosis where neutrophil proteolytic activity plays a major role. We postulated that neutrophil recruitment and activation participating in AAA growth may originate in part from repeated episodes of periodontal bacteremia. METHODS AND FINDINGS: Our results show that neutrophil activation in human AAA was associated with Neutrophil Extracellular Trap (NET) formation in the IntraLuminal Thrombus, leading to the release of cell-free DNA. Human AAA samples were shown to contain bacterial DNA with high frequency (11/16), and in particular that of Porphyromonas gingivalis (Pg), the most prevalent pathogen involved in chronic periodontitis, a common form of periodontal disease. Both DNA reflecting the presence of NETs and antibodies to Pg were found to be increased in plasma of patients with AAA. Using a rat model of AAA, we demonstrated that repeated injection of Pg fostered aneurysm development, associated with pathological characteristics similar to those observed in humans, such as the persistence of a neutrophil-rich luminal thrombus, not observed in saline-injected rats in which a healing process was observed. CONCLUSIONS: Thus, the control of periodontal disease may represent a therapeutic target to limit human AAA progression

Place de la médecine bucco-dentaire fondée sur la preuve

National audienceDans une vingtaine de jours s'ouvrira l'édition 2011 du Congrès de l'Association Dentaire Française (ADF). Comme chaque année, le Palais des congrès de paris sera, pendant une semaine, le lieu d'informations, de formations, d'échanges entre les professionnels de santé investis dans la médecine buccodentaire. << Le bien-être du patient, thème retenu cette année, sera au coeur des préoccupations de tous. Autour des secrétaires généraux, du staff de l'ADF, du président du Congrès, le comité scientifique a préparé un programme dans lequel les séances classiques et les essentielles côtoieront ]es incontournables et les fondamentales

L'implant biologique en médecine bucco-dentaire est-il la voie d'avenir ?

National audienc

Innovation et recherche en odontologie

National audienceDans les chapitres précédents ont été traitées les innovations en odontologie qui sont dans les cabinets de chirurgie dentaire ou en passe d'y être. Ces innovations en implantologie, en endodontie, en chirurgie et en imagerie sont toutes le fait de l'interdisciplinarité. Elles sont nées de partenariats entre plusieurs acteurs dont des chercheurs, notamment des chercheurs chirurgiens-dentistes

Neuroblastome et anomalies dentaires (à propos de 11 cas)

RENNES1-BU Santé (352382103) / SudocSudocFranceF

Fusobacterium, Capnocytophaga, Prevotella, et Treponema dans les bactériémies et infections extra-buccales

La cavité buccale est constituée d une flore bactérienne riche et complexe. Des bactériémies à microorganismes buccaux sont observées après la mastication, le brossage des dents et des soins dentaires comme les extractions ou les détartrages. Ces bactériémies peuvent être à l origine d infections extra-buccales, la plus connue étant l endocardite infectieuse. Une étude menée sur 9 patients du CHU de Pontchaillou (Rennes) et une revue bibliographique ont permis d observer des infections d origine buccale dans de nombreux sites extra-buccaux tels que le cerveau, le cœur, les poumons, le foie, les articulations Cette étude s est intéressée particulièrement aux Fusobacterium, Capnocytophaga, Prevotella et Treponema et 91 cas d infection ont été recensés: pour 41% le foyer infectieux primaire est resté indéterminé, pour 34% la source infectieuse était buccale, pour 14% l origine buccale a été suspectée mais non établie de façon certaine et pour 11% l infection n était pas d origine buccale. Bien que la proportion d infections d origine buccale certaine ou suspectée soit importante, ces résultats montrent aussi que l isolement d un microorganisme buccal n oriente pas les cliniciens à rechercher systématiquement un foyer infectieux buccal.The oral cavity hosts a rich and complex bacterial flora. Bacteremia due to oral microorganisms are observed after chewing or tooth brushing and also dental procedures such as extraction or scaling. These bacteremia may cause extra-oral infections such as the well known infective endocarditis. A study on 9 patients from Pontchaillou Teaching Hospital (Rennes) and a literature review showed infections of oral origin in many extra-oral sites such as the brain, the heart, the lungs, the liver, the joints ... This study focused specifically on Fusobacterium, Capnocytophaga, Prevotella and Treponema and 91 cases of infection have been reported: for 41% the primary focus of infection remained undefined, for 34% the source of infection was oral, for 14% oral origin was suspected but not established with certainty and for 11% the source of infection was not from an oral origin. Despite the fact that the proportion of certain or suspected oral origin infections is important, these results also showed that the isolation of an oral microorganism doesn t guide clinicians to systematically look for an oral focus of infection.RENNES1-BU Santé (352382103) / SudocSudocFranceF