[Show abstract][Hide abstract] ABSTRACT: Matrix-associated laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) is a rapid and simple microbial identification method. Previous reports using the Biotyper system suggested that this technique requires a preliminary extraction step to identify Gram-positive rods (GPRs), a technical issue that may limit the routine use of this technique to identify pathogenic GPRs in the clinical setting. We tested the accuracy of the MALDI-TOF MS Andromas strategy to identify a set of 659 GPR isolates representing 16 bacterial genera and 72 species by the direct colony method. This bacterial collection included 40 C. diphtheriae, 13 C. pseudotuberculosis, 19 C. ulcerans, and 270 other Corynebacterium isolates, 32 L. monocytogenes and 24 other Listeria isolates, 46 Nocardia, 75 Actinomyces, 18 Actinobaculum, 11 Propionibacterium acnes, 18 Propionibacterium avidum, 30 Lactobacillus, 21 Bacillus, 2 Rhodococcus equi, 2 Erysipelothrix rhusiopathiae, and 38 other GPR isolates, all identified by reference techniques. Totals of 98.5% and 1.2% of non-Listeria GPR isolates were identified to the species or genus level, respectively. Except for L. grayi isolates that were identified to the species level, all other Listeria isolates were identified to the genus level because of highly similar spectra. These data demonstrate that rapid identification of pathogenic GPRs can be obtained without an extraction step by MALDI-TOF mass spectrometry.
[Show abstract][Hide abstract] ABSTRACT: Central venous device infections are associated with increased physical and psychological morbidity, mortality, length of stay, and costs. The aim of this study was to prove the efficacy of pulsatile flushing to prevent the bacterial colonization of vascular access devices. One hundred and forty four tests using 576 polyurethane short venous access catheters were performed. Four catheters per test were polluted with a fibronectin-serum albumin solution. Three were filled with a Staphylococcus aureus broth; one served as negative control. One contaminated catheter was not flushed (positive control), and two were flushed (10 mL.sec(-1)) with normal saline solution, either by ten successive boluses of 1 mL each or by one bolus of 10 mL. Each catheter was cultivated. The S. aureus quantity observed after continuous flushing was significantly higher than that observed after pulsative flushing (P<0.001). Unflushed catheters were 20.71 and 6.42 times more polluted than catheters flushed with the pulsative method or the continuous method, respectively. Pulsative flushing was at least twice as effective as continuous flushing in reducing the S. aureus count. Pulsative flushing is more effective than continuous flushing in reducing the endoluminal contamination. Pulsative flushing is a simple, effective, and inexpensive technique to reduce catheter bacterial colonization.
Medical Devices: Evidence and Research 01/2014; 7:379-83.
[Show abstract][Hide abstract] ABSTRACT: Arnault Tzanck was at the origins of French transfusion and the founder of the first blood centre worldwide. This article retraces his career and personal itinerary and that path which led him to give his build the country's first organized and modern blood transfusion structure.
Journal of Medical Biography 11/2013; 21(4):211-9.
[Show abstract][Hide abstract] ABSTRACT: The epidemiology of acute paediatric osteoarticular infections (OAI) has recently evolved, mainly due to the improvement of microbiological diagnosis. We conducted a prospective study to analyse the recent epidemiology and the clinical evolution of paediatric OAI in order to validate the adequacy of our probabilistic first-line antibiotic treatment (intraveinous cefamandole + gentamicin). All children suspected of community acquired OAI were included and followed-up for 3 years. The etiologic diagnosis was based on blood cultures, joint aspirations and bone punctures. All osteoarticular (OA) samples were systematically inoculated into blood culture bottles. Real-time universal 16S rRNA and PCR targeted on Staphylococcus aureus, Kingella kingae, Streptococcus pneumoniae and Streptococcus pyogenes were performed twice a week. From 17 March 2007 to 26 February 2009, 98 septic arthritis, 70 osteomyelitis, 23 osteoarthritis and six spondylodiscitis were analysed. A portal of entry was suspected in 44% of cases, including 55% of otorhinolaryngological infections. C reactive protein was the most sensitive inflammatory marker. PCR increased by 54% the performance of bacteriological diagnosis. Among the patients completely investigated (blood culture and OAI samples), there were 63% documented OAI. The main pathogens found were K. kingae (52%), S. aureus (28%), S. pyogenes (7%), S. pneumoniae (3%) and Streptococcus agalactiae (2%). All isolated bacteria were sensitive to the probabilist treatment and outcome was favorable. PCR has significantly improved the performance and the delay of IOA diagnosis in children, for which K. kingae turned out to be the first causative agent. The probabilistic treatment was active against the main bacteria responsible for paediatric OAI.
Clinical Microbiology and Infection 09/2013; 19(9):822-8. · 4.58 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We report on six cases of Pasteurella multocida (P. multocida) meningitis occurring between 2001 and 2011 by a French nationwide active surveillance network of paediatric bacterial meningitis (ACTIV/GPIP). The cases accounted for 0.15 % of the paediatric meningitis cases reported between 2001 and 2011 in France, all in infants <4 months old. A review of the literature allowed us to gather information on 42 other cases of P. multocida meningitis in infants <1 year old reported since 1963. Among all 48 cases, 44 % were newborns. An animal source of the infection, including 39 household dogs and cats, was suspected or identified in 42 of 48 cases. A traumatic contact between the child and a pet occurred in 8 % of cases, and a vertical transmission from mother to child during birth in 10.4 %. Most of the time, the infection resulted from non-traumatic contact between the child and the pet, through licking or sniffing. The absence of host risk factors suggests that an immature immune system is responsible, given the young age of the children. Although complications, especially neurological lesions, were not rare (37.5 %), the long-term outcome was usually good. Four infants died of meningitis. This rare disease could be prevented by reducing contact between infants and household pets, and by performing simple hygiene measures before handling babies.
European Journal of Clinical Microbiology 04/2013; 32(9). · 3.02 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Matrix-associated laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is a rapid and simple microbial identification method. Previous reports using the Biotyper system suggested that this technique requires a preliminary extraction step to identify Gram-positive rods (GPRs), a technical issue that may limit the routine use of this technique to identify pathogenic GPRs in the clinical setting. We tested the accuracy of the MALDI-TOF MS Andromas strategy to identify a set of 659 GPR isolates representing 16 bacterial genera and 72 species by the direct colony method. This bacterial collection included 40 C. diphtheriae, 13 C. pseudotuberculosis, 19 C. ulcerans, and 270 other Corynebacterium isolates, 32 L. monocytogenes and 24 other Listeria isolates, 46 Nocardia, 75 Actinomyces, 18 Actinobaculum, 11 Propionibacterium acnes, 18 Propionibacterium avidum, 30 Lactobacillus, 21 Bacillus, 2 Rhodococcus equi, 2 Erysipelothrix rhusiopathiae, and 38 other GPR isolates, all identified by reference techniques. Totals of 98.5% and 1.2% of non-Listeria GPR isolates were identified to the species or genus level, respectively. Except for L. grayi isolates that were identified to the species level, all other Listeria isolates were identified to the genus level because of highly similar spectra. These data demonstrate that rapid identification of pathogenic GPRs can be obtained without an extraction step by MALDI-TOF mass spectrometry.
Journal of clinical microbiology 06/2012; 50(8):2702-7. · 4.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: During the Second Empire in France (1828–1913), a soldier called Jacob drew Parisian crowds by performing so-called miraculous cures. The craze that he created allowed to live from his “miracles” all of his life. He performed a kind of group hypno-therapy, which prefigures the methods used by today's evangelists. His career and biography are depicted here, and an attempt at explaining how he was able convince his patients they were cured.
[Show abstract][Hide abstract] ABSTRACT: Clin Microbiol Infect 2012; 18: 1117-1125 ABSTRACT: All organisms usually isolated in our laboratory are now routinely identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) using the Andromas software. The aim of this study was to describe the use of this strategy in a routine clinical microbiology laboratory. The microorganisms identified included bacteria, mycobacteria, yeasts and Aspergillus spp. isolated on solid media or extracted directly from blood cultures. MALDI-TOF MS was performed on 2665 bacteria isolated on solid media, corresponding to all bacteria isolated during this period except Escherichia coli grown on chromogenic media. All acquisitions were performed without extraction. After a single acquisition, 93.1% of bacteria grown on solid media were correctly identified. When the first acquisition was not contributory, a second acquisition was performed either the same day or the next day. After two acquisitions, the rate of bacteria identified increased to 99.2%. The failures reported on 21 strains were due to an unknown profile attributed to new species (9) or an insufficient quality of the spectrum (12). MALDI-TOF MS has been applied to 162 positive blood cultures. The identification rate was 91.4%. All mycobacteria isolated during this period (22) were correctly identified by MALDI-TOF MS without any extraction. For 96.3% and 92.2% of yeasts and Aspergillus spp., respectively, the identification was obtained with a single acquisition. After a second acquisition, the overall identification rate was 98.8% for yeasts (160/162) and 98.4% (63/64) for Aspergillus spp. In conclusion, the MALDI-TOF MS strategy used in this work allows a rapid and efficient identification of all microorganisms isolated routinely.
Clinical Microbiology and Infection 09/2011; 18(11):1117-25. · 4.58 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We report a case of ventriculoperitoneal (VP) shunt infection in a 3-year-old boy caused by the food-borne pathogen Listeria monocytogenes, subsequent to acute peritonitis. This unusual presentation of central nervous system (CNS) listeriosis underlines the ability of the bacteria to form and survive within biofilms on indwelling medical devices. Bacterial persistence may lead to treatment failure and spreading. We highlight the helpfulness of specific quantitative real-time PCR for the hly gene (PCR-hly) for the diagnosis and follow-up of such infections in detecting bacterial persistence within medical devices despite effective antibiotic treatment. Only the surgical replacement of the VP shunt will resolve the infection.
Journal of clinical microbiology 09/2011; 49(11):3924-7. · 4.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Listeria monocytogenes is a bacterial pathogen that can invade the central nervous system (CNS), causing meningoencephalitis and brain abscesses. The diagnosis of CNS listeriosis, based on the isolation of the bacteria in the cerebrospinal fluid (CSF), can be difficult because of previous antibiotic treatment and a low number of bacteria in the CSF. To improve the sensitivity of microbiological diagnosis, we have developed a real-time PCR assay for detecting and quantifying L. monocytogenes DNA in the CSF. The designed primers specifically amplify the L. monocytogenes hly gene, which encodes listeriolysin O, a pore-forming cytolysin. The PCR assay for the hly gene (PCR-hly) provides reproducible quantitative results over a wide dynamic range of concentrations and was highly sensitive while detecting a single gene copy/ml. By assaying a large panel of bacterial species, including species secreting pore-forming cytolysin, we determined the specificity of the PCR-hly, which exclusively detects the L. monocytogenes DNA. We then analyzed 214 CSF samples from patients suspected of having CNS listeriosis. PCR-hly was positive in all cases in which L. monocytogenes was isolated by culture. Positive PCR-hly of the CSF was also obtained for five additional, clinically confirmed cases of CNS listeriosis for which bacterial cultures were negative presumably due to previous treatment with antibiotics. As a complement to classical bacteriological CSF culture, our designed real-time PCR-hly assay proved to be valuable by enhancing the rapidity and the accuracy of the diagnosis of CNS infection by L. monocytogenes. In addition, the quantitative results provided may, in some instances, be useful for the follow-up of patients under treatment.
Journal of clinical microbiology 09/2011; 49(11):3917-23. · 4.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: New Aspergillus species have recently been described with the use of multilocus sequencing in refractory cases of invasive aspergillosis. The classical phenotypic identification methods routinely used in clinical laboratories failed to identify them adequately. Some of these Aspergillus species have specific patterns of susceptibility to antifungal agents, and misidentification may lead to inappropriate therapy. We developed a matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry (MS)-based strategy to adequately identify Aspergillus species to the species level. A database including the reference spectra of 28 clinically relevant species from seven Aspergillus sections (five common and 23 unusual species) was engineered. The profiles of young and mature colonies were analysed for each reference strain, and species-specific spectral fingerprints were identified. The performance of the database was then tested on 124 clinical and 16 environmental isolates previously characterized by partial sequencing of the β-tubulin and calmodulin genes. One hundred and thirty-eight isolates of 140 (98.6%) were correctly identified. Two atypical isolates could not be identified, but no isolate was misidentified (specificity: 100%). The database, including species-specific spectral fingerprints of young and mature colonies of the reference strains, allowed identification regardless of the maturity of the clinical isolate. These results indicate that MALDI-TOF MS is a powerful tool for rapid and accurate identification of both common and unusual species of Aspergillus. It can give better results than morphological identification in clinical laboratories.
Clinical Microbiology and Infection 05/2011; 17(5):750-5. · 4.58 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Preoperative samples in the context of complicated appendicitis (CA) are rarely collected, and there is no consensus regarding the optimal antibiotic therapy in children. To help optimize empirical preoperative treatment, we studied clinical and bacteriologic data from a prospective cohort of 93 children with CA in a French hospital. All the bacteria isolated from peritoneal fluids were identified, using phenotypic and/or molecular techniques. The most commonly recovered species were Escherichia coli (71%), Streptococcus group milleri (34%), anaerobes (20%), and Pseudomonas aeruginosa (19%). The association piperacillin-tazobactam is an accurate choice of empirical therapy as it is active against 97% of bacteria. A third-generation cephalosporin with metronidazole in association with an aminoglycoside is a good alternative. Although antibiotic use may be considered as an adjunct to surgical intervention of CA, the appropriate use of preoperative antibiotics is essential and must be constantly reevaluated according to the bacterial epidemiology.
[Show abstract][Hide abstract] ABSTRACT: We describe a case of acute chest syndrome associated with Bordetella bronchiseptica pneumonia in a child with sickle cell disease. B. bronchiseptica is recognized as an important pathogen of the respiratory tract for a large variety of animal species. This zoonotic agent has been frequently associated with chronic and recurrent infections. In humans, the bacterium acts as an opportunistic pathogen affecting mostly immunocompromised patients or those with preexisting respiratory diseases. This case and literature review provides an opportunity to discuss the risk factors, treatment, follow-up, and prevention of such zoonotic infections in the context of a lack of cross-protection of new pertussis vaccines.
Archives de Pédiatrie 01/2011; 18(1):41-44. · 0.41 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Antibiotics have been shown to improve hidradenitis suppurativa (HS) patients but complete remission is rare using these treatments.
To assess the efficacy and safety of a combination of oral rifampin, moxifloxacin and metronidazole in long-lasting refractory HS.
We retrospectively studied 28 consecutive HS patients including 6, 10 and 12 Hurley stage 1, 2 and 3 patients, respectively. Complete remission, defined as a clearance of all inflammatory lesions including hypertrophic scars, was the main outcome criterion of the study.
Complete remission was obtained in 16 patients, including 6/6, 8/10 and 2/12 patients with Hurley stage 1, 2 and 3, respectively (p=0.0004). The median duration of treatment to obtain complete remission was 2.4 (range 0.9-6.5) and 3.8 months (range 1.6-7.4) in stage 1 and 2 patients, respectively, and 6.2 and 12 months in the 2 stage 3 patients. Main adverse events of the treatments were gastrointestinal disorders (64% of patients) and vaginal candidiasis (35% of females). Reversible tendinopathy and hepatitis occurred in 4 and 1 patient, respectively.
Complete remission of refractory HS can be obtained using broad-spectrum antibiotics and Hurley staging is a prognostic factor of response to the treatment.