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M Drancourt

Publications and source records attributed to M Drancourt.

At least 19 recordsLinked to original sources

Interactions between Mycobacterium xenopi, amoeba and human cells.

Outbreaks due to Mycobacterium xenopi have been linked with contaminated water. M. xenopi has been shown to interact with the biofilm formed in water distribution systems and to be hosted by free-living Acanthamoeba. The present study investigated the interaction between M. xenopi and A. polyphaga amoeba, and between M. xenopi and human fibroblast HEL cells. Examination using the light microscopy together with electronic and confocal microscopy demonstrated that M. xenopi was located within the amoeba and in HEL cells. The Light Cycler measurement of the M. xenopi:A. polyphaga DNA ratio and the M. xenopi:HEL cell DNA ratio demonstrated intra-amoebal and intracellular growth of M. xenopi with doubling-times of five-days and 10 days, respectively. Intra-amoebal M. xenopi survived protozoan encystment and germination. These data demonstrate that M. xenopi is a facultative intra-amoebal and intracellular pathogen. Testing intra-amoebal M. xenopi might be necessary to properly evaluate decontamination procedures for hospital water supply systems in order to achieve eradication.

Acanthamoeba↗

[Icteric Fort Bragg fever: a case report with nosological discussion].

INTRODUCTION: Ictero-hemorrhagic leptospirosis is an endemic disease in France. Weil's disease, a form of leptospirosis, is well known. Fort Bragg fever is characterized by a constant pretibial papular lesion. First described in the USA, this non icteric form of leptospirosis is usually benign. We report the first French case of a mixed form of leptospirosis. EXEGESIS: A 52-year-old man living in South East France suffered from fever and myalgias associated with a pretibial papular lesion. A severe icterus appeared and permitted a diagnosis of leptospirosis. CONCLUSION: Our case recalls the clinical presentation of Fort Bragg fever, which is recognized through its inflammatory pretibial lesion associated or not with icterus.

Anti-Bacterial Agents↗

[CT evaluation of total HIP prosthesis infection].

PURPOSE: To evaluate the ability of CT imaging to detect infectious lesions in total hip prosthesis. PATIENTS AND METHODS: CT was performed in 17 cases of suspected total hip prosthesis infection. Images were reviewed to evaluate for the presence of soft tissue abscess, hip joint effusion or fistula and peri-prosthetic lucency or erosion at bone window setting. The feasibility of CT imaging is assessed with regards to metallic artifacts. RESULTS: Infection was confirmed in 10 hips. A soft tissue abscess was present in 8 of these cases, in association to a joint effusion, presumably septic, in 7 cases. A fistula was identified in 8 cases. A peri-prosthetic lucency was present in 10 cases, 7 of which with infection, and erosions were noted in 4 patients, 2 of which with infection. Metallic artifacts reduced image quality but did not prevent detection of soft tissue abscesses. CONCLUSION: CT is useful for detection of soft tissue abscesses in patients with infected hip prosthesis. CT is useful for surgical planning or follow-up of patients treated conservatively.

Aged↗

Systematic 16S rRNA gene sequencing of atypical clinical isolates identified 27 new bacterial species associated with humans.

Clinical microorganisms isolated during a 5-year study in our hospital that could not be identified by conventional criteria were studied by 16S rRNA gene sequence analysis. Each isolate yielded a > or =1,400-bp sequence containing <5 ambiguities which was compared with the GenBank 16S rRNA gene library; 1,404 such isolates were tested, and 120 were considered unique (27 isolates) or rare (< or =10 cases reported in the literature) human pathogens. Eleven new species, "Actinobaculum massiliae," "Candidatus Actinobaculum timonae," Paenibacillus sanguinis, "Candidatus Bacteroides massiliae," Chryseobacterium massiliae, "Candidatus Chryseobacterium timonae," Paenibacillus massiliensis, "Candidatus Peptostreptococcus massiliae," "Candidatus Prevotella massiliensis," Rhodobacter massiliensis, and "Candidatus Veillonella atypica" were identified. Sixteen species were obtained from humans for the first time. Our results show the important role that 16S rRNA gene sequence-based bacterial identification currently plays in recognizing unusual and emerging bacterial diseases.

Adolescent↗

Nosocomial influenza in children.

Influenza is the most important cause of acute respiratory illness leading to hospitalization among children during community epidemics. This illness can cause extensive nosocomial outbreaks with serious morbidity and mortality among specific groups of children. Paediatric patients with community-acquired influenza and healthcare workers are the main reservoir for the nosocomial spread of the virus. During epidemics in the community, testing for influenza should be requested in all children with compatible symptoms admitted in the hospital, and measures should be introduced for the prevention or early control of an outbreak. Recent advances in the management of influenza include rapid diagnoses based on antigen detection and the identification of the new neuraminidase inhibitors zanamivir and oseltamivir. Annual vaccination against influenza of children with high-risk conditions, their family members and healthcare workers is the principle measure for the prevention of nosocomial outbreaks. Although vaccination against influenza appears to be cost-effective at all ages in terms of prevention of illness, related hospitalizations, deaths, reduction of healthcare costs and productivity loss, vaccination coverage among target groups is limited.

Antiviral Agents↗

Growth on blood agar discriminates Mycobacterium avium and Mycobacterium intracellulare.

Mycobacterium intracellulare and Mycobacterium avium (MAC) require specialized culture and identification procedures. To simplify the diagnosis, we inoculated reference strains, and 85 M. avium and 12 M. intracellulare clinical isolates, on egg-based and sheep blood agar. After 5 days of culture, there were significantly more colonies on sheep blood than on egg-based agar for M. avium (ratio: 250.5 +/- 209) but not for M. intracellulare (ratio: 0.44 +/-0.11). Using a ratio > or = 20, the sensitivity of the identification of an MAC isolate as M. avium was 97.65%, the specificity was 100%, and the positive predictive value was 100%. Differential growth on egg-based and blood agar is an aid to the identification of MAC isolates.

Agar↗

Blood agar and Mycobacterium tuberculosis: the end of a dogma.

Incidental blood agar-based recovery of Mycobacterium tuberculosis led us to further investigate this routine medium for primary isolation and culture of M. tuberculosis. Fifteen respiratory tract and eight lymph node Ziehl-Neelsen-positive specimens were inoculated in parallel into tubes containing egg-based medium and 5% sheep blood agar. Colonies appeared sooner on this medium than on the egg-based medium, but this difference was not significant (P = 0.11, analysis of variance [ANOVA] test). Further experiments compared the growth of 38 respiratory and lymph node M. tuberculosis isolates when subcultured on the two media. After 6 days of incubation, 21 of 38 isolates had grown on blood agar, and the mean number of colonies was significantly greater on blood agar than on the egg-based medium (P < 0 0.001, ANOVA test). These results demonstrate that M. tuberculosis grows easily on blood agar within 1to 2 weeks, indicating that this basic medium is suitable for laboratory diagnosis of tuberculosis in addition to other media. Laboratories that routinely use prolonged incubations of blood plates, for example, for the recovery of Bartonella species, should consider the potential safety implications of encountering this highly infectious pathogen.

Agar↗

Molecular identification of Staphylococcus lugdunensis in a patient with meningitis.

A 12-year-old child developed meningitis 6 days after a third ventriculostomy by endoscopy. A coagulase-negative Staphylococcus sp. was isolated in pure culture from the cerebrospinal fluid and was definitely identified as Staphylococcus lugdunensis after the 16S ribosomal DNA gene and rpoB gene were sequenced. This report describes the first case of S. lugdunensis meningitis.

Catheters, Indwelling↗

Is ventilator-associated pneumonia an independent risk factor for death?

BACKGROUND: Ventilator-associated pneumonia (VAP) has been implicitly accused of increasing mortality. However, it is not certain that pneumonia is responsible for death or whether fatal outcome is caused by other risk factors for death that exist before the onset of pneumonia. The aim of this study was to evaluate the attributable mortality caused by VAP by performing a matched-paired, case-control study between patients who died and patients who were discharged from the intensive care unit after more than 48 h of mechanical ventilation. METHODS: During the study period, 135 consecutive deaths were included in the case group. Case-control matching criteria were as follows: (1) diagnosis on admission that corresponded to 1 of 11 predefined diagnostic groups; (2) age difference within 10 yr; (3) sex; (4) admission within 1 yr; (5) APACHE II score within 7 points; (6) ventilation of control patients for at least as long as the cases. Precise clinical, radiologic, and microbiologic definitions were used to identify VAP. RESULTS: Analysis was performed on 108 pairs that were matched with 91% of success. There were 39 patients (36.1%) who developed VAP in each group. Multivariate analysis showed that renal failure, bone marrow failure, and treatment with corticosteroids but not VAP were independent risk factors for death. There was no difference observed between cases and controls concerning the clinical and microbiologic diagnostic criteria for pneumonia. CONCLUSION: Ventilator-associated pneumonia does not appear to be an independent risk factor for death.

Adult↗

Phylogenetic analyses of Klebsiella species delineate Klebsiella and Raoultella gen. nov., with description of Raoultella ornithinolytica comb. nov., Raoultella terrigena comb. nov. and Raoultella planticola comb. nov.

The phylogenetic relationships of the type strains of 9 Klebsiella species and 20 species from 11 genera of the family Enterobacteriaceae were investigated by performing a comparative analysis of the sequences of the 16S rRNA and rpoB genes. The sequence data were phylogenetically analysed by the neighbourjoining and parsimony methods. The phylogenetic inference of the sequence comparison confirmed that the genus Klebsiella is heterogeneous and composed of species which form three clusters that also included members of other genera, including Enterobacter aerogenes, Erwinia clusters I and II and Tatumella. Cluster I contained the type strains of Klebsiella pneumoniae subsp. pneumoniae, Klebsiella pneumoniae subsp. rhinoscleromatis and Klebsiella pneumoniae subsp. ozaenae. Cluster II contained Klebsiella ornithinolytica, Klebsiella planticola, Klebsiella trevisanii and Klebsiella terrigena, organisms characterized by growth at 10 degrees C and utilization of L-sorbose as carbon source. Cluster III contained Klebsiella oxytoca. The data from the sequence analyses along with previously reported biochemical and DNA-DNA hybridization data support the division of the genus Klebsiella into two genera and one genogroup. The name Raoultella is proposed as a genus name for species of cluster II and emended definitions of Klebsiella species are proposed.

DNA, Bacterial↗

Use of rpoB gene analysis for detection and identification of Bartonella species.

Identification of Bartonella species is of increasing importance as the number of infections in which these bacteria are involved increases. To date, these gram-negative bacilli have been identified by various serological, biochemical, and genotypic methods. However, the development of alternative tools is required, principally to circumvent a major risk of contamination during sample manipulation. The aim of our study was to investigate the possible identification of various Bartonella species by comparison of RNA polymerase beta-subunit gene (rpoB) sequences. This approach has previously been shown to be useful for the identification of members of the family Enterobacteriaceae (C. M. Mollet, M. Drancourt, and D. Raoult, Mol. Microbiol. 26:1005-1011, 1997). Following PCR amplification with specific oligonucleotides, a 825-bp region of the rpoB gene was sequenced from 13 distinct Bartonella strains. Analysis of these sequences allowed selection of three restriction enzymes (ApoI, AluI, and AflIII) useful for discerning the different strains by PCR-restriction fragment length polymorphism (PCR-RFLP) analysis. To confirm the potential value of such an approach for identification of Bartonella, the rpoB PCR was then applied to 94 clinical samples, and the results obtained were identical to those obtained by our reference PCR method. Twenty-four isolates were also adequately identified by PCR-RFLP analysis. In all cases, our results were in accordance with those of the reference method. Moreover, conserved regions of DNA were chosen as suitable primer targets for PCR amplification of a 439-bp fragment which can be easily sequenced.

Animals↗