Intérêts et limites de la PCR quantitative en temps réel pour le diagnostic de la pneumocystose au C.H.U de Nantes (étude rétrospective allant de décembre 2006 à juin 2007)

Pneumocystis jiroveci est responsable de pneumopathie grave chez les sujets immunodéprimés. Le diagnostic de pneumocystose est difficile et repose encore actuellement sur la mise en évidence du micro-organisme dans le LBA à l examen microscopique par des techniques modérément sensibles. Depuis les années 1990, les progrès réalisés dans le domaine de la biologie moléculaire, ont permis de développer des techniques de PCR très sensibles pour la recherche de Pneumocystis. Le but de cette étude était de mettre en place une PCR en temps réel quantitative pour la détection de P. jiroveci dans les LBA et d en déterminer les intérêts et les limites dans le diagnostic de pneumocystose. De décembre 2006 à juin 2007, 201 LBA, issus de 189 patients, ont été recueillis au laboratoire de Mycologie/Parasitologie du C.H.U de Nantes. La recherche de pneumocystes a été réalisée par microscopie et par PCR, avec une concordance entre les deux techniques de 81,1%. La grande sensibilité de la PCR a permis de suspecter fortement une pneumocystose chez 5 patients, négatifs en microscopie, ainsi qu une colonisation chez 32 patients. Les résultats quantitatifs de la PCR, nous ont permis de proposer un cut-off afin de différencier les patients colonisés de ceux développant une pneumocystose. L évaluation de la qualité des LBA grâce à une gamme d albumine, est néanmoins nécessaire pour rendre ce seuil plus discriminant.NANTES-BU Médecine pharmacie (441092101) / SudocSudocFranceF

LETTERS TO THE EDITOR Can 16S rRNA PCR be the solution for a rapid detection of Propionibacterium acnes in surgical shoulder or spine samples? Comments on " A rapid method for detecting Propionibacterium acnes in surgical biopsy specimens from the shoulder "

International audienceno abstrac

LETTERS TO THE EDITOR Can 16S rRNA PCR be the solution for a rapid detection of Propionibacterium acnes in surgical shoulder or spine samples? Comments on " A rapid method for detecting Propionibacterium acnes in surgical biopsy specimens from the shoulder "

International audienceno abstrac

In vitro emergence of fluoroquinolone resistance in Cutibacterium (formerly Propionibacterium ) acnes and molecular characterization of mutations in the gyrA gene

International audienceIn vitro occurrence of levofloxacin (LVX) resistance in C. acnes and characterization of its molecular background were investigated. The mutation frequency was determined by inoculation of 108 cfu of C. acnes ATCC 11827 (LVX MIC = 0.25 mg/L) on LVX-containing agar plates. The progressive emergence of resistance was studied by a second exposure to increasing LVX concentrations. For mutants, the QRDR regions including the gyrA and parC genes were sequenced and compared to both C. acnes ATCC 11827 and C. acnes KPA171202 reference sequences (NC006085). The importance of the efflux pump system in resistance was investigated by using inhibitors on selected resistant mutants with no mutation in the QRDR. C. acnes growth was observed on LVX-containing plates with mutation frequencies of 3. 8 cfu × 10-8 (8 × MIC) and 1.6 cfu × 10-7 (4 × MIC). LVX resistance emerged progressively after one-step or two-step assays. In LVX-resistant isolates, the MIC ranged from 0.75 to >32 mg/L. Mutations were detected exclusively in the gyrA gene. Ten genotypes were identified: G99 C, G99 D, D100N, D100 H, D100 G, S101L, S101W, A102 P, D105 H and A105 G. Mutants S101L and S101W were always associated with a high level of resistance. Mutants with no mutation in the QRDR were more susceptible when incubated with an efflux pump inhibitor (phenyl-arginine β-naphthylamide) only, suggesting, for the first time, the expression of such a system in C. acnes LVX-resistant mutants

Draft Genome Sequences of Four Propionibacterium acnes Strains Isolated from Implant-Related Infections

International audiencePropionibacterium acnes was previously described as a potential implant-related pathogen. Here, we report the draft genome sequence of four P. acnes strains, isolated from spine material, hip arthroplasty, and knee arthroplasty infections in France belonging to different sequence types (ST18, ST27, and ST36)

Draft Genome Sequence of an Erythromycin-Resistant Propionibacterium acnes Isolate Recovered from Folliculitis of the Scalp

International audiencePropionibacterium acnes is now well-known and recognized for its implication in the pathogenesis of acne vulgaris. Here, we report the draft genome sequence of an erythromycin-resistant P. acnes strain isolated from a case of folliculitis of the scalp belonging to phylotype IA1 and sequence type 18 (ST18)

Staphylococcus succinus Infective Endocarditis, France

International audiencenfective endocarditis is a rare condition in humans and is associated with high illness and death rates. We describe a case of infective endocarditis caused by Staphylococcus succinus bacteria in France. We used several techniques for susceptibility testing for this case to determine the oxacillin profile

Principal component analysis, a useful tool to study cyclin-dependent kinase-inhibitor’s effect on cerebral ischaemia

International audienceAbstract Stroke is a leading cause of acute death related in part to brain oedema, blood–brain barrier disruption and glial inflammation. A cyclin-dependant kinase inhibitor, (S)-roscovitine, was administered 90 min after onset on a model of rat focal cerebral ischaemia. Brain swelling and Evans Blue tissue extravasation were quantified after Evans Blue injection. Combined tissue Evans Blue fluorescence and immunofluorescence of endothelial cells (RECA1), microglia (isolectin-IB4) and astrocytes (glial fibrillary acidic protein) were analysed. Using a Student’s t-test or Mann–Whitney test, (S)-roscovitine improved recovery by more than 50% compared to vehicle (Mann–Whitney, P < 0.001), decreased significantly brain swelling by 50% (t-test, P = 0.0128) mostly in the rostral part of the brain. Main analysis was therefore performed on rostral cut for immunofluorescence to maximize biological observations (cut B). Evans Blue fluorescence decreased in (S)-roscovitine group compared to vehicle (60%, t-test, P = 0.049) and was further supported by spectrophotometer analysis (Mann–Whitney, P = 0.0002) and Evans Blue macroscopic photonic analysis (t-test, P = 0.07). An increase of RECA-1 intensity was observed in the ischaemic hemisphere compared to non-ischaemic hemisphere. Further study showed, in the ischaemic hemisphere that (S)-roscovitine treated group compared to vehicle, showed a decrease of: (i) endothelial RECA-1 intensity of about 20% globally, mainly located in the cortex (−28.5%, t-test, P = 0.03); (ii) Microglia’s number by 55% (t-test, P = 0.006) and modulated reactive astrocytes through a trend toward less astrocytes number (15%, t-test, P = 0.05) and astrogliosis (21%, t-test, P = 0.076). To decipher the complex relationship of these components, we analysed the six biological quantitative variables of our study by principal component analysis from immunofluorescence studies of the same animals. Principal component analysis differentiated treated from non-treated animals on dimension 1 with negative values in the treated animals, and positive values in the non-treated animals. Interestingly, stroke recovery presented a negative correlation with this dimension, while all other biological variables showed a positive correlation. Dimensions 1 and 2 allowed the identification of two groups of co-varying variables: endothelial cells, microglia number and Evans Blue with positive values on both dimensions, and astrocyte number, astrogliosis and brain swelling with negative values on dimension 2. This partition suggests different mechanisms. Correlation matrix analysis was concordant with principal component analysis results. Because of its pleiotropic complex action on different elements of the NeuroVascular Unit response, (S)-roscovitine may represent an effective treatment against oedema in stroke

Emergence of methicillin resistant Staphylococcus epidermidis resistant to linezolid: activity of ceftaroline versus ceftobiprole in a French University French Hospital

International audienceNo abstract availabl

Safety and Efficacy of Ceftaroline in Neonates With Staphylococcal Late-onset Sepsis: A Case Series Analysis

International audienceTreatment of late-onset neonatal staphylococcal sepsis is sometimes challenging with feared side effects of vancomycin, increasing minimal inhibitory concentrations and questions about catheter management. In case of failure, ceftaroline was administered as a compassionate treatment in 16 infants (gestational age of less than 32 weeks and less than 28 postnatal days), whose first-line treatment failed. We report 11 successes and no severe adverse drug reactions. Larger data are required to confirm these encouraging results