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Contexte : Une epreuve de lecture critique d'article (LCA) sera introduite en 2008 dans l'examen classant national (ECN). Les rares travaux consacres a cette epreuve suggerent une concordance mediocre des corrections. But : Identifier certains facteurs lies a la concordance des corrections d’une epreuve de LCA. Sujets et methodes : 59 etudiants volontaires de DCEM 2 et DCEM 3 ont ete soumis a une epreuve de LCA dans les conditions prevues pour l'ECN. Trois correcteurs ayant prepare l’epreuve (choix d’article, questions et reponses attendues selon 16 questions, grilles de correction (s), ponderations), ont corrige chaque copie de facon independante, sans grille puis avec une grille. L'accord entre les 3 couples de correcteurs, avec ou sans grille, pour les 16 questions, soit 96 couples, a ete mesure par les coefficients de correlation intraclasse (CCI). La valeur mediane du CCI pour chaque facteur (questions, grille ou non, questions ou resume, couples de correcteurs) a ete comparee aux autres CCI par le test de Mann-Whitney ; les facteurs independants de variations du CCI ont ete determines par une analyse de regression multiple. Resultats : 6 questions sur 16, l’usage de la grille, et l’un des couples de correcteurs etaient lies de facon independante aux CCI. Conclusion : La concordance des corrections d'une epreuve de LCA semble dependre fortement de la qualite de l’epreuve et des correcteurs ; le recours a une grille de correction pourrait representer un facteur d’amelioration d’impact modeste de cette concordance.

Contexte : L'introduction d'une epreuve de lecture critique d'articles dans l'examen classant national en 2008 implique de former les etudiants et de mettre au point une procedure reproductible de correction. Actuellement la formation est tres variable entre les differentes facultes et la reproductibilite de ce type d'epreuve est inconnue. But : Evaluer la reproductibilite de la correction d'une epreuve de lecture critique d'articles dans des conditions proches de celles de l'examen national classant. Sujets et methodes : 59 etudiants volontaires de 2e et 3e annees du deuxieme cycle des etudes medicales ont passe une epreuve surveillee de trois heures, sur un article original en francais, comportant 10 questions validees et un resume de 250 mots au plus. Trois enseignants ayant prepare le dossier de l'epreuve ont corrige en aveugle les questions et le resume selon 16 items, sans grille de correction. L'accord entre les trois paires de correcteurs a ete apprecie par les coefficients de correlation intra classe (CCI). Resultats : En moyenne, l'accord entre les correcteurs etait modere ou mediocre : CCI = 0,68 (intervalle de confiance a 95 % : 0,52 - 0,80), CCI = 0,71 (0,55 - 0,81) et CCI = 0,48 ( 0,26 - 0,65) selon la paire. Cette concordance etait variable suivant les items (tres mauvaise pour deux questions). Elle etait meilleure pour les questions que pour le resume pour 2 des 3 paires de correcteurs. Conclusion : Cette methode de correction de l'epreuve de lecture critique d'articles est peu reproductible. L'impreparation actuelle des etudiants et des enseignants est probablement un facteur aggravant.

Resume Objectif Identifier une strategie de depistage du SARM ( Staphylococcus aureus resistant a la meticilline) a l’admission en service de soins de suite geriatrique ayant une efficacite et un cout acceptables par comparaison avec ceux d’une strategie maximaliste combinant le depistage de 6 sites de prelevement. Methode Le depistage du SARM a ete effectue de facon prospective pendant 3 mois pour tous les patients admis dans un service de soins de suite et de readaptation geriatrique, au moyen de prelevements des narines, des aisselles, des urines, des cicatrices, des ulceres cutanes et des escarres. Six strategies ont ete definies combinant differents sites de prelevement. Leur cout et leur efficacite ont ete compares a ceux d’une strategie maximaliste associant le prelevement des 6 sites. Resultats Le depistage par le prelevement combine des 6 sites etait la strategie la plus efficace mais aussi la plus couteuse. La strategie la moins couteuse ne comportait que le prelevement des ulceres et des escarres mais son efficacite etait de 45 %. La strategie pour laquelle la perte d’efficacite etait la plus faible par rapport a la strategie de reference maximaliste etait le prelevement des ulceres et des escarres associe a un prelevement des narines : son efficacite etait de 91 % et son cout 2,5 fois moins important que celui de la strategie de reference. Discussion Une etude preliminaire realisee sur une courte duree a etabli une strategie de depistage du SARM adaptee aux specificites d’un service de soins de suite et a son recrutement. La capacite d’identifier la meilleure strategie de depistage de SARM dans un service de soins de suite et de readaptation peut etre un point important pour controler la diffusion du SARM.

Background Hygienic hand disinfection using alcohol-based handrubs (AHRs) is an alternative method to conventional handwashing in hospital wards. Because a documented choice of such products would consider data from in-care evaluation, we designed a comparative study of 9 AHRs both in vitro and in vivo in actual care conditions. Methods The bactericidal activity of AHRs was first measured in vitro against 4 hospital strains exhibiting multiple antibiotic resistance: Acinetobacter baumannii, Staphylococcus aureus, Pseudomonas aeruginosa, and Enterobacter aerogenes . In a second time, AHRs were tested in an intensive care unit for antibacterial activity against the cutaneous flora of personnel hands and for acceptance by the care personnel. Results The 9 AHRs could be classified in 3 groups on the basis of their in vitro activity: products of the first group showed a bactericidal activity higher than 4 log 10 against the 4 strains. Only 1 of these products presented simultaneously an effective antibacterial activity against the cutaneous flora of care personnel hands and a good acceptance by the care personnel. Conclusion The in vitro study allowed the differentiation of the AHRs tested on the basis of bactericidal activity, but evaluation in an in-care situation allowed further discrimination through both antibacterial activity and acceptance. Thus, the combination of in vitro and in vivo evaluations should provide helpful arguments in the choice of AHRs.

Genetic relationships among 46 isolates of Mycobacterium avium recovered from 37 patients in a 2,500-bed hospital from 1993 to 1998 were assessed by pulsed-field gel electrophoresis (PFGE) and PCR amplification of genomic sequences located between the repetitive elements IS 1245 and IS 1311 . Each technique enabled the identification of 27 to 32 different patterns among the 46 isolates, confirming that the genetic heterogeneity of M. avium strains is high in a given community. Furthermore, this retrospective analysis of sporadic isolates allowed us (i) to suggest the existence of two remanent strains in our region, (ii) to raise the question of the possibility of nosocomial acquisition of M. avium strains, and (iii) to document laboratory contamination. The methods applied in the present study were found to be useful for the typing of M. avium isolates. In general, both methods yielded similar results for both related and unrelated isolates. However, the isolates in five of the six PCR clusters were distributed among two to three PFGE patterns, suggesting that this PCR-based method may have limitations for the analysis of strains with low insertion sequence copy numbers or for resolution of extended epidemiologic relationships.

The nasopharyngeal carriage of penicillin-susceptible and penicillin-resistant Streptococcus pneumoniae (PSSp and PRSp, respectively) was analyzed in 116 children attending a day care center in Rouen, France, by three observation periods in November, January, and March of the winter of 1993 to 1994. The carriage rate of S. pneumoniae was found to be 47.7, 47.3, and 49.6% at each different observation period, and PRSp accounted for 42.2, 40.3, and 40.6% of pneumococcal isolates, respectively. The 52 isolates recovered in November were distributed in 34 electrophoretic types (ETs) by multilocus enzyme electrophoresis; 15 PRSp isolates, all of serotype 23F, belonged to a clonal complex of five ETs, representing the dominant population of PRSp in November. The temporal pattern of S. pneumoniae carriage was studied in 17 children who were colonized at the three periods by multilocus enzyme analysis of their isolates. The PSSp isolated, exhibiting distinct ETs, were transient only among these day care attendees. In contrast, most of the PRSp isolated in January and March belonged to the clonal complex. Thus, this PRSp population was resident in the day care center throughout the study period.

Resume Nous rapportons deux observations d'endocardite a Corynebacterium diphtheriae survenues chez des patients porteurs de valves prothetiques. Une des souches etait toxinogene. L'analyse de la litterature concerne 52 observations decrites entre 1893 et 1994; 12 des souches etaient toxinogenes. Ces infections surviennent chez des patients jeunes, souvent porteurs d'une cardiopathie congenitale. Des complications sont frequemment decrites; le traitement actuel comporte une antibiotherapie et le recours a la chirurgie cardiaque dans 25 % des cas. Un nombre croissant d'infections systemiques a C. diphtheriae sont actuellement decrites; ces infections sont favorisees par de mauvaises conditions d'hygiene. La poursuite d'une couverture vaccinale efficace est necessaire compte-tenu de la recrudescence recente de cas de diphterie.

The effects of 16 different beta-lactam-fosfomycin combinations against 50 bloodstream enterococci were compared by a disk diffusion technique. Cefotaxime exhibited the best interaction. By checkerboard studies, the cefotaxime-fosfomycin combination provided a synergistic bacteriostatic effect against 45 of the 50 isolates (MIC of cefotaxime at which 90% of the isolates were inhibited, >2,048 micrograms/ml; MIC of fosfomycin at which 90% of the isolates were inhibited, 128 micrograms/ml; mean of fractional inhibitory concentration indexes, 0.195). By killing curves, cefotaxime (at 64 micrograms/ml) combined with fosfomycin (at > or = 64 micrograms/ml) was bactericidal against 6 of 10 strains tested.

A synergistic bactericidal effect between penicillin, vancomycin, and gentamicin has been described against enterococci highly resistant to beta-lactams and glycopeptides. Since such a synergy was also observed in vitro between ceftriaxone, teicoplanin, and gentamicin against Enterococcus faecium 70/90, the efficacy of different combinations including penicillin or ceftriaxone, vancomycin or teicoplanin, and gentamicin was compared in vivo in experimental endocarditis. In vitro, all four triple combinations provided a bactericidal effect. In rabbits, after a 5-day treatment, the ceftriaxone-vancomycin-gentamicin combination was the most effective, both in reducing the total bacterial titers and in eradicating the subpopulation resistant to the synergy. Compared with the 5-day regimen, 10- and 20-day regimens of ceftriaxone-vancomycin-gentamicin, each followed by a 3-day antibiotic-free period, increased the number of sterilized animals but failed to avoid the emergence of resistant bacteria, which occurred in 10%-20% of animals.

Bacteremia due to Pasteurella pneumotropica occurs infrequently. We report a case of septicemia in a 72-year-old woman who had no underlying illness. The microorganism was isolated from 10 blood cultures and identified by conventional and molecular methods. This is the first reported case of P. pneumotropica septicemia in an immunocompetent patient. The history of P. pneumotropica diseases in animals and humans and their varied clinical features are reviewed.

The in vitro colonization of three commercial heart valve leaflets by Staphylococcus aureus was investigated. The leaflets, made of pyrolytic carbon alloyed with or without silicon, displayed similar surface properties (wettability, roughness) and were readily colonized by S. aureus that formed patchy biofilms on the three supports. A proteomic approach was used to assess the physiological status of biofilm populations by comparing their protein maps to those of bacteria cultured as free cells in the presence or absence of biofilm substratum. Principal component analysis (PCA) revealed, for each tested leaflet, statistical relationships between the protein maps of the biofilm and free-floating microbial populations. A spot-by-spot comparison of protein levels on two-dimensional electropherograms showed that many proteins were accumulated or underproduced by microbial populations grown in the presence of a leaflet compared with protein levels in control free populations. The number of accumulated proteins was noticeably higher than that of underproduced polypeptides. This protein overproduction was emphasized in biofilm populations. Several proteins, some of which were identified, were differentially produced by both surface-associated planktonic and biofilm-grown cell populations compared with control free-cell ones cultured in the absence of leaflet, whatever the leaflet tested. The potential of this proteomic approach for fighting against microbial adhesion and biofilm formation is discussed.

This study was designed to determine the effect of ornithine α-ketoisocaproate (O-KIC), a compound reducing muscle protein breakdown in physiological conditions, on liver factors involved in drug metabolism in rats with acute retrograde pyelonephritis. 91 rats were assigned to 7 groups differing in the level of food intake, induced infection, and the treatment by O-KIC (168 mg/kg bw/day). Rats were killed on the third day. O-KIC increased nitrogen balance and weight gain in controls, but not in malnourished infected or non-infected rats. Liver glutathione was significantly reduced by O-KIC in malnourished infected and non-infected rats. Though O-KIC induced a rise in liver microsomal proteins in control and infected animals, it decreased cytochrome P-450 in controls, and aminopyrine demethylase in both control and infected groups.

An in vitro bacteriostatic synergy between beta-lactam and glycopeptide antibiotics has been recently described against isolates of Enterococcus faecium moderately resistant to penicillin and highly resistant to vancomycin. The relevance of this synergy in a rabbit endocarditis model was evaluated. Penicillin was tested at low- (LoD) and high-dose (HiD) regimens, alone or combined with vancomycin and/or gentamicin. Compared with controls, after a 5-day treatment: LoD penicillin, vancomycin, gentamicin, LoD penicillin plus gentamicin or vancomycin, and vancomycin-gentamicin were not effective; LoD penicillin-vancomycin caused a small reduction of bacterial titers in vegetations that was strongly enhanced by adding gentamicin; HiD penicillin-gentamicin, the most effective regimen, was not significantly better than LoD penicillin-vancomycin-gentamicin. These results suggest that the relative in vivo inefficacy of penicillin-vancomycin might be related to the fact that this combination was poorly bactericidal, and the triple combination of LoD penicillin-vancomycin-gentamicin or the combination of HiD penicillin-gentamicin should be considered in the treatment of serious infections due to beta-lactam- and glycopeptide-resistant enterococci.

OBJECTIVE: To study the effects of infection and malnutrition on liver glutathione and cytochrome P450 (P450) in rats. DESIGN: Controlled experimental groups (12 groups). ANIMALS: Adult male Sprague-Dawley rats. INTERVENTIONS: Experimental endocarditis, pyelonephritis, or peritonitis were caused. Controls included free-fed rats and sham-operated rats, pair-fed to infected animals. Infection was verified by tissue culture. Rats were killed 3 days (acute infection) or 10 days (chronic infection, except endocarditis) after the induction of infection. RESULTS: Sham rats had lower liver weights, liver/body weight, and liver glutathione values than controls. Infected rats had larger liver weights and liver/body weight ratios and liver glutathione content than shams, and larger liver/body weight ratios than controls (acute infection). Infected rats had lower P450 values than both shams and controls. CONCLUSION: The malnutrition associated with infection caused decreased liver weight and glutathione content. Infection increased the liver weight, and liver glutathione content, but caused severe reduction in liver P450. If the same finding is true in infected patients, it could have consequences for the management of such patients.

During a 2-week period, three infants with a cough lasting at least 8 days with whoops, were admitted to the pediatric unit; Bordetella pertussis was isolated from nasopharyngeal aspirates collected from the three infants. Approximately 1 week later, a nurse working on the same unit developed influenza-like symptoms followed by whooping cough; B pertussis was isolated. Isolates from the nurse and from one of the infants were shown to be indistinguishable by pulsed-field gel electrophoresis. These data demonstrate that B pertussis transmission to healthcare workers is possible and emphasize the need to use respiratory protection devices (Droplet Precautions) for healthcare workers having close contact with infected children.

The ciprofloxacin efficacy was compared to that of tobramycin in an Escherichia coli pyelonephritis model in rat. Treatments started 48 h after ligation of the left ureter and inoculation of the bladder and continued for 5 days. Ciprofloxacin (2.5 mg/kg/d and 10 mg/kg/d) was administered intravenously either in a single daily dose or in 2 divided doses at 12 h intervals. Tobramycin (2.5 mg/kg/d and 10 mg/kg/d) was administered by the intramuscular route, in a single daily dose. Ciprofloxacin 10 mg/kg/d was as efficacious as tobramycin irrespective of dosage schedule. Ciprofloxacin 2.5 mg/kg/d was more effective when given twice a day than once.

AIM: To evaluate the effect of glutamine on intestinal mucosa integrity, glutathione stores and acute phase response in protein-depleted rats during an inflammatory shock. METHODS: Plasma acute phase proteins (APP), jejunal APP mRNA levels, liver and jejunal glutathione concentrations were measured before and one, three and seven days after turpentine injection in 4 groups of control, protein-restricted, protein-restricted rats supplemented with glutamine or protein powder. Bacterial translocation in mesenteric lymph nodes and intestinal morphology were also assessed. RESULTS: Protein deprivation and turpentine injection significantly reduced jejunal villus height, and crypt depths. Mucosal glutathione concentration significantly decreased in protein-restricted rats. Before turpentine oil, glutamine supplementation restored villus heights and glutathione concentration (3.24 ± 1.05 vs 1.72 ± 0.46 μmol/g tissue, P < 0.05) in the jejunum, whereas in the liver glutathione remained low. Glutamine markedly increased jejunal α1-acid glycoprotein mRNA level after turpentine oil but did not affect its plasma concentration. Bacterial translocation in protein-restricted rats was not prevented by glutamine or protein powder supplementation. CONCLUSION: Glutamine restored gut glutathione stores and villus heights in malnourished rats but had no preventive effect on bacterial translocation in our model.

ObjectiveThe aim of this study was to analyze the interaction of surface free energy and roughness characteristics of different pyrolytic carbon heart valves with three bacterial species on biofilm formation.MethodsThree pyrolytic carbon heart valves (St Jude Medical [St Jude Medical Inc, Minneapolis, Minn], Sulzer Carbomedics [CarboMedics Inc, Austin, Tex], and MedicalCV [Medical Incorporated, Inver Grove Heights, Minn]) were tested. Roughness was measured by interferential microscopy and surface free energy by contact angle technique. To obtain a biofilm, prostheses were inserted into a bioreactor with Staphylococcus aureus P209, Staphylococcus epidermidis RP62A, or Pseudomonas aeruginosa PAO1. Adhesion was quantified by counting sessile bacteria. Morphologic characteristics of biofilms were evaluated with scanning electron microscopy.ResultsRoughness analysis revealed significant differences between the MedicalCV (35.18 ± 4.43 nm) valve and St Jude Medical (11.03 ± 3.11 nm; P < .0001) and Sulzer Carbomedics (8.80 ± 1.10 nm; P < .0001) valves. Analysis of surface free energy revealed a higher level for the MedicalCV valve (41.03 mJ · m−2) than for both the Sulzer Carbomedics (38.93 mJ · m−2) and St Jude Medical (31.51 mJ · m−2) models. These results showed a correlation between surface free energy and bacterial adhesion for S epidermidis and P aeruginosa species. Regardless of the support, we observed significant adhesion differences for the three bacterial species. S aureus was the most adherent species, S epidermidis was the least, and P aeruginosa was intermediate.ConclusionsOur results suggest that adhesion of S epidermidis and P aeruginosa are dependent on pyrolytic carbon surface free energy and roughness, although S aureus adhesion appears to be independent of these factors. Improvement of pyrolytic carbon physicochemical properties thus could lead to a reduction in valvular prosthetic infections.

Tolerance to vancomycin and teicoplanin in 90 clinical isolates of coagulase-negative staphylococci (CoNS) was investigated by time-kill curve methodology. Only six strains, belonging to the Staphylococcus lugdunensis species, exhibited tolerance. The seven other S. lugdunensis strains tested displayed weak susceptibility to the bactericidal activity of glycopeptides compared to the other CoNS. These phenomena are of concern, since S. lugdunensis is recognized as one of the most pathogenic CoNS.

The present study evaluated the usefulness of a real-time polymerase chain reaction (rtPCR) assay for the detection of Neisseria meningitidis (Nm) and genogrouping on skin lesion biopsies in patients with purpura fulminans (PF). Retrospective single-centre study. Adult and paediatric intensive care units at the University Hospital of Rouen. All patients admitted between January 2000 and January 2006, with a final diagnosis of PF and for which a skin biopsy and blood cultures were performed, were included. Skin biopsy and blood cultures were used for culture and rtPCR. Thirty-four patients fulfilled the criteria (27 children and 7 adults). Nm rtPCR performed on skin biopsy was positive in 100% (34/34) of cases, compared with only 14.7% (5/34) for skin culture (p = 0.0001). rtPCR genogrouping on skin biopsy was positive in 58.8% (20/34) of the cases compared with 14.7% (5/34) for skin culture (p = 0.0013). For patients (n = 17) in whom rtPCR was performed both on blood and skin biopsy, skin biopsy gave a significantly higher rate of Nm detection [100% (17/17) vs. 58.8% (10/17); p = 0.023] and genogroup characterisation [76.5% (13/17) vs. 35.3% (6/17); p = 0.045] than blood. We encountered no specimen with culture-positive and rtPCR-negative results (negative predictive value of rtPCR 100%). In suspected PF cases, skin biopsy is more reliable to identify Nm and its genogroup than blood or, probably, CSF, especially when PCR methods are used. This could help the implementation of public health interventions, especially concerning a vaccination policy.

A multilocus sequence analysis of ten virulence-associated genes was performed to study the genetic relationships between 29 Clostridium difficile isolates of various origins, hosts and clinical presentations, and selected from the main lineages previously defined by multilocus sequence typing (MLST) of housekeeping genes. Colonization-factor-encoding genes (cwp66, cwp84, fbp68, fliC, fliD, groEL and slpA), toxin A and B genes (tcdA and tcdB), and the toxin A and B positive regulator gene (tcdD) were investigated. Binary toxin genes (cdtA and cdtB) were also detected, and internal fragments were sequenced for positive isolates. Virulence-associated genes exhibited a moderate polymorphism, comparable to the polymorphism of housekeeping genes, whereas cwp66 and slpA genes appeared highly polymorphic. Isolates recovered from human pseudomembranous colitis cases did not define a specific lineage. The presence of binary toxin genes, detected in five of the 29 isolates (17 %), was also not linked to clinical presentation. Conversely, toxigenic A−B+ isolates defined a very homogeneous lineage, which is distantly related to other isolates. By clustering analysis, animal isolates were intermixed with human isolates. Multilocus sequence analysis of virulence-associated genes is consistent with a clonal population structure for C. difficile and with the lack of host specificity. The data suggest a co-evolution of several of the virulence-associated genes studied (including toxins A and B and the binary toxin genes) with housekeeping genes, reflecting the genetic background of C. difficile, whereas flagellin, cwp66 and slpA genes may undergo recombination events and/or environmental selective pressure.

To identify a strategy of MRSA screening (methicillin-resistant Staphylococcus aureus) on admission to geriatric rehabilitation units, which would lead to acceptable efficacy and cost compared with a reference maximaliste strategy combining all six sampling sites. Method MRSA screening was conducted prospectively for 3 months in all the patients admitted to a geriatric follow-up and rehabilitation unit, using samples from the nostrils, armpits, urine scars cutaneous ulcers and sores. Six strategies were defined combing different sampling sites. Their efficacy and cost were compared with those of a maximaliste strategy combining the 6 sampling sites.Combined screening of all six sites was the most effective but also the most expensive strategy. The least expensive strategy used only samples from ulcers and sores, but its efficacy was of only 45%. The strategy with the lowest loss of efficacy compared to the reference strategy combined the sampling of ulcers and sores and sampling from the nostrils: it was efficient in 91% and its cost was 2.5 fold lower than the cost of the reference strategy.A preliminary, short term study established an MRSA screening strategy adapted to the specificities of a geriatric rehabilitation unit and its recruitment. The ability to define the optimal strategy for MRSA screening in a geriatric rehabilitation and follow-up unit may be an important factor in controlling the diffusion of MRSA.

A multiplex PCR toxigenic culture approach was designed for simultaneous identification and toxigenic type characterization of Clostridium difficile isolates. Three pairs of primers were designed for the amplification of (i) a species-specific internal fragment of the tpi (triose phosphate isomerase) gene, (ii) an internal fragment of the tcdB (toxin B) gene, and (iii) an internal fragment of the tcdA (toxin A) gene allowing distinction between toxin A-positive, toxin B-positive (A+B+) strains and toxin A-negative, toxin B-positive (A−B+) variant strains. The reliability of the multiplex PCR was established by using a panel of 72 C. difficile strains including A+B+, A−B−, and A−B+ toxigenic types and 11 other Clostridium species type strains. The multiplex PCR assay was then included in a toxigenic culture approach for the detection, identification, and toxigenic type characterization of C. difficile in 1,343 consecutive human and animal stool samples. Overall, 111 (15.4%) of 721 human samples were positive for C. difficile ; 67 (60.4%) of these samples contained A+B+ toxigenic isolates, and none of them contained A−B+ variant strains. Fifty (8%) of 622 animal samples contained C. difficile strains, which were toxigenic in 27 (54%) cases, including 1 A−B+ variant isolate. Eighty of the 721 human stool samples (37 positive and 43 negative for C. difficile culture) were comparatively tested by Premier Toxins A&B (Meridian Bioscience) and Triage C. difficile Panel (Biosite) immunoassays, the results of which were found concordant with toxigenic culture for 82.5 and 92.5% of the samples, respectively. The multiplex PCR toxigenic culture scheme described here allows combined diagnosis and toxigenic type characterization for human and animal C. difficile intestinal infections.

A multilocus sequence typing (MLST) scheme was developed to study the genetic relationships and population structure of 72 Clostridium difficile isolates from various hosts, geographic sources, PCR ribotypes, and toxigenic types (determined by PCR targeting tcdA and tcdB genes). MLST was performed by DNA sequence analysis of seven housekeeping genes ( aroE , ddl , dutA , tpi , recA , gmk , and sodA ). The number of alleles ranged from five ( dutA and ddl ) to eleven ( recA ). Allelic profiles allowed the definition of 34 different sequence types (STs). These STs lacked correlation with geographic source but were well correlated to toxigenic type. The dendrogram generated from a matrix of pairwise genetic distances showed that animal isolates did not constitute a distinct lineage from human isolates and that there was no hypervirulent lineage within the population of toxigenic human isolates (isolates recovered from pseudomembranous colitis and antibiotic-associated diarrhea did not cluster in distinct lineages). However, A − B + variant isolates shared the same ST that appeared as a divergent lineage in the population studied, indicating a single evolutionary origin. The population structure was further examined by analysis of allelic polymorphism. The dendrogram generated from composite sequence-based analysis revealed a homogeneous population associated with three divergent lineages, one of which was restricted to A − B + variant isolates. C. difficile exhibited a clonal population structure, as revealed by the estimation of linkage disequilibrium ( Ia ) between loci. The analysis of alleles within clonal complexes estimated that point mutation generated new alleles at a frequency eightfold higher than recombinational exchange, and the congruence of the dendrograms generated from separate housekeeping loci confirmed the mutational evolution of this species.

Objective: Hospital-acquired urinary tract infections (HUTI) represent a significant impairment in the quality of health care. Incidence in catheterized patients has been estimated at approximately 20%, however few data are available in urologic patients. We report a prospective surveillance program over 6 years in our urologic department and evaluate its evolution. Methods: Population consists of all patients admitted to the urology ward for 48 hours or more over a 6-year period from 1994. Data recorded: age, gender, duration of stay, insertion and removal of catheters, diagnosis of HUTI. Analysis: calculation of incidence, and incidence density for HUTI and for catheter-related HUTI, analysis of trends by χ 2 trend test. Results: A total of 10,054 consecutive patients were included, 52% were catheterized. The median incidence of catheter-related HUTI in catheterized patients was 13.0%, the incidence density was 25.1 HUTI/1000 patient-days of catheterization. The proportion of HUTI and specific catheter-related HUTI patients decreased, respectively from 8.4% and 14.2% to 6.5% and 12.3% during the study period ( p Conclusion: The rate of HUTI was not as high as previously reported, perhaps due to a controlled catheter policy. Surveillance was associated with a significant decrease in infection rates, suggesting a beneficial feedback effect. Evaluation of diagnoses and surgical procedures would ensure an optimal quality control program.

Several studies have previously reported synergistic effects between vancomycin and a given β-lactam or a given aminoglycoside against methicillin-resistant Staphylococcus aureus (MRSA) strains. The aim of our study was to exhaustively compare the effects of different combinations of a β-lactam, vancomycin, and/or an aminoglycoside against 32 clinical MRSA strains with different aminoglycoside susceptibility patterns. The effects of 26 different β-lactam–vancomycin and 8 different aminoglycoside-vancomycin combinations were first studied using a disk diffusion screening method. The best interactions with vancomycin were observed with either imipenem, cefazolin, or netilmicin. By checkerboard studies, imipenem-vancomycin and cefazolin-vancomycin each provided a synergistic bacteriostatic effect against 22 strains; the mean fractional inhibitory concentration (FIC) indexes were 0.35 and 0.46 for imipenem-vancomycin and cefazolin-vancomycin, respectively. The vancomycin-netilmicin combination provided an indifferent effect against all of the 32 strains tested; the mean of FIC index was 1.096. The mean concentrations of imipenem, cefazolin, netilmicin, and vancomycin at which FIC indexes were calculated were clinically achievable. Killing experiments were then performed using imipenem, cefazolin, netilmicin, and vancomycin at one-half of the MIC, alone and in different combinations, against 10 strains. The vancomycin-netilmicin regimen was rarely bactericidal, even against strains susceptible to netilmicin. The imipenem-vancomycin and cefazolin-vancomycin combinations were strongly bactericidal against six and five strains, respectively. The addition of netilmicin markedly enhanced the killing activity of the combination of cefazolin or imipenem plus vancomycin, but only for the MRSA strains against which the β-lactam–vancomycin combinations had no bactericidal effect. It is noteworthy that the latter strains were both susceptible to netilmicin and heterogeneously resistant to methicillin.

The discrimination between Staphylococcus epidermidis strains that contaminate and infect blood cultures is a daily challenge for clinical laboratories. The results of PCR detection of putative virulence genes were compared for contaminating strains, sepsis-related strains, catheter strains, and saprophytic strains. Multiplex PCR was used to explore the atlE gene, which is involved in initial adherence, the intercellular adhesion gene cluster ( ica ), which mediates the formation of the biofilm, and the agrA , sarA , and mecA genes, which might contribute to the pathogenicity of S. epidermidis . Whereas the atlE , agrA , and sarA genes were almost ubiquitously amplified, the ica and mecA genes were detected significantly more in infecting strains than in contaminating strains ( P ≤ 0.02) and thus appeared to be related to the potential virulence of S. epidermidis .

Nasal surveillance cultures were performed for 54 patients exhibiting ≥10 3 CFU of methicillin-resistant coagulase-negative staphylococci per ml in central venous catheter (CVC) rinse cultures over a 6-month period. Forty-two of the nasal cultures yielded growth of methicillin-resistant coagulase-negative staphylococci, and 33 of the 42 cultures contained organisms that belonged to the same species as the CVC isolates. Of the 33 same-species isolates, 20 appeared to be identical strains by pulsed-field gel electrophoresis analysis. These data suggest that measures should be taken to reduce cross-contamination between the respiratory tract and intravascular devices. However, the potential interest in detecting methicillin-resistant coagulase-negative staphylococcus carriage in high-risk patients is hampered by the lack of sensitivity of nasal surveillance cultures.

Although nosocomial febrile illness (NFI) is common in hospitalized patients, it has been less extensively studied in the elderly.To determine the frequency, causes, and risk factors of NFI in elderly inpatients.This prospective study involved 608 patients (or = 65 years of age) admitted in an acute geriatric unit. Investigators followed this cohort until 1 of the following events occurred: development of NFI, discharge from the geriatric unit, or death. The cause of NFI was classified into 3 groups: infectious, noninfectious, and no apparent diagnosis. We systematically studied 17 comorbid conditions, 6 drugs, and 7 invasive procedures. For comparison, the patients were stratified into 2 groups: patients with NFI and patients without NFI.Sixty-six patients (10.9%) with NFI were identified. They were compared with the remaining 542 patients without NFI. In 49 patients (74%) with NFI, the cause was infectious; in 9 (13.5%), it was noninfectious; and in 8 (12.5%), there was no apparent cause. After multivariate analysis, only fecal incontinence (odds ratio [OR], 5.54; 95% confidence interval [CI], 2.13-14.5), congestive heart failure (OR, 2.97; 95% CI, 1.53-5.76), and pressure ulcers (OR, 2.93; 95% CI, 1.19-7.17) were independent risk factors for NFI. The number of invasive procedures preceding the febrile episode was a significant predictor of infection (OR, 3.68; 95% CI, 1.14-9.21).Nosocomial febrile illness is a common event in elderly hospitalized patients. In 74% of the patients with NFI, an infection is found. Measures to decrease infectious NFI in the elderly require a reduction in the number of invasive procedures.

The performance characteristics of the E-test (AB Biodisk, Solna, Sweden), the ATB Staph, the Rapid ATB Staph, and the Vitek GPS-503 card (bioMérieux, La Balme Les Grottes, France) methods for the detection of oxacillin resistance in a collection of staphylococci with a high proportion of troublesome strains were evaluated. Sixty-four Staphylococcus aureus strains and 76 coagulase-negative staphylococcal strains were tested. All strains were mecA positive and were characterized by the oxacillin agar screen plate test; 75 (53.6%) were found to be heterogeneous by a large-inoculum oxacillin disk diffusion assay, and oxacillin MICs for 89 (63.6%) were ≤32 μg/ml. Three (4.7%) S. aureus strains and 25 (32.9%) coagulase-negative strains were classified as susceptible by the E-test, as defined by the National Committee for Clinical Laboratory Standards (NCCLS) oxacillin breakpoint (MIC ≤ 2 μg/ml). The ATB Staph method failed to detect oxacillin resistance in 7 (11%) S. aureus isolates and 32 (42.1%) coagulase-negative isolates. The MICs for all but six of these discrepant isolates were ≤16 μg/ml. The Rapid ATB Staph method was tested against S. aureus strains only and yielded 15 (23.4%) false-susceptible results for strains for which the MICs were ≤32 μg/ml. The Vitek system was the best-performing system, since it failed to detect oxacillin resistance in only 3 (4.7%) S. aureus strains and 15 (19.7%) coagulase-negative strains, the MICs for all of which were ≤2 μg/ml. These data indicate that (i) the performance of the two ATB Staph systems can be limited when the prevalence of borderline-heteroresistant staphylococci is high and (ii) the unreliability of the E-test and the Vitek methods for detecting resistant coagulase-negative strains might be reduced by the potential revision of the oxacillin breakpoint currently recommended by the NCCLS.

The present experiment was undertaken to verify if the demand of tissues for pteroylglutamic (folic) acid, evaluated by serum clearance and urinary excretion of folates, is different between multiparous dairy cows in late gestation (five gestating dry cows, 52.6 (SD 8.4) d before parturition), and in early lactation (four lactating non-gestating cows, 18.0 (SD 5.9) d after parturition). On day 1 the cows received one intravenous (i.v.) injection of 50 micrograms pteroylmonoglutamic acid/kg body weight (BW). Blood samples were taken at 0, 5, 15, 30 min, 1, 2, 4, 8 and 24 h after the i.v. injection. On day 3 the cows received one intramuscular (i.m.) injection of 0.3 mg pteroylmonoglutamic acid/kg BW. Blood and urine samples, as well as urine volume, were taken at 0, 1, 2, 4, 8, 12, 24, 36 and 48 h after the i.m. injection. On days 5, 6 and 7 a daily i.m. injection of 0.5 mg pteroylmonoglutamic acid/kg BW was given in an attempt to saturate tissues with folates. Then the cows received one i.v. (day 8) and one i.m. (day 10) injection of pteroylmonoglutamic acid according to the same procedures described previously for days 1 and 3. On day 12 plasma volume was determined. Before tissue saturation, serum clearance of folates during the 24 h following an i.v. injection was similar for gestating and lactating cows but after tissue saturation serum clearance was slower for lactating than gestating cows (stage x saturation, P = 0.04). The percentage of folates excreted in urine was not affected by the physiological stage (P > or = 0.6) or the level of tissue saturation (P > or = 0.5). In conclusion, serum clearance and urinary excretion of pteroylmonoglutamic acid seem to support the hypothesis that, in multiparous cows, although there are no deficiency symptoms, tissue demand for folic acid is high, especially during gestation.

Nineteen extended-spectrum beta-lactamase (ESBla)-producing Klebsiella pneumoniae isolates from Rouen Hospital were investigated for their implication in nosocomial outbreaks: in addition to antibiotic susceptibility testing, the ESBlas were characterized by isoelectric focusing, and the genetic relationships between the strains were analyzed by multilocus enzyme electrophoresis using a combined polyacrylamide electrophoresis-electrophoretic transfer technique. Four isoelectric focusing beta-lactamase patterns and 11 enzyme electrophoretic types (ETs) among the strains tested were described. Three strains isolated in the same neurological unit over a 7-day period exhibited an SHV 3 beta-lactamase (pI 7.0) and were assigned to a common ET. Three of five strains isolated from patients in a rehabilitation center over a 6-week period harbored an SHV 4 beta-lactamase (pI 7.8) and exhibited the same ET. These results differentiate nosocomial transmission from sporadic cases and provide evidence that multilocus enzyme electrophoresis is a potential tool for studying genetic relationships between strains harboring a common ESBla.

Using an experimental endocarditis model, we studied the activity of daptomycin used alone or in combination with gentamicin against an Enterococcus faecium strain that was highly resistant to glycopeptides and susceptible to gentamicin. In vitro, the MIC of daptomycin was 1 micrograms/ml. In vivo, daptomycin appeared to be effective only when it was used in a high-dose regimen, i.e., 12 mg/kg of body weight every 8 h (-2.5 log10 CFU/g versus controls; P < 0.05), particularly when it was combined with gentamicin (-5.0 log10 CFU/g versus controls; P < 0.01). Since the distribution of daptomycin into cardiac vegetations, as evaluated by autoradiography, appeared to be homogeneous, the poor in vivo activity of daptomycin was considered to be related to its high degree of protein binding, as suggested by killing curves studies. Since the MIC of teicoplanin for the vancomycin-resistant E. faecium strain used in the study was only 64 micrograms/ml and since an in vitro synergy between teicoplanin at high dose and gentamicin was observed, a high-dose regimen of teicoplanin, i.e., 40 mg/kg every 12 h, was also assessed in vivo. This treatment provided marginal activity only when it was combined with gentamicin (-2.3 log10 CFU/g versus controls; P < 0.05). These results suggest that the levels of daptomycin or teicoplanin in serum required to cure experimental endocarditis caused by a highly glycopeptide-resistant strain of E. faecium would not be achievable in humans.

We report the case of a pediatrician who developed meningococcal meningitis after performing endotracheal intubation without protection on a child who was suspected of having meningoencephalitis. This case emphasizes the necessity for healthcare workers who perform high-risk procedures to use personal protection devices (ie, respirators and protective goggles). Unprotected healthcare workers with high exposure toNeisseria meningitidisshould receive chemoprophylaxis.

Summary Gemella morbillorum is mostly involved in subacute endocarditis in elderly patients with an underlying valve disease. We report a case of endocarditis in a young immunocompetent adult, with a major perforation of the native aortic valve conducting to an immediate surgical replacement. Other infections due to Gemella morbillorum are reviewed.

Reduction of lipoic acid by bacteria coupled to oxygen consumption during glucose absorption can be followed potentiometrically with a pair of gold and reference electrodes in a minimal culture medium. The variations in potential as a function of time have the shape of a wave. A theoretical expression was derived relating the size of the original inoculum to the time preceding the appearance of the wave. The validity of that relation was experimentally verified with Escherichia coli, and the time needed for a drop of 100 mV was determined. Detection of small inocula, e.g., down to a range of 10 viable E. coli per liter, is possible in about 11 h by yeast extract stimulation. The method, technically simple and adequately sensitive, suggests the possibility of automated detectors of bacterial contaminations.

Resume Les pyelonephrites experimentales fournissent des renseignements du plus grand interet sur la physiopathologie et le traitement de ces infections. Les conditions d'un traitement optimal sur la reaction inflammatoire et sur les phenomenes suppuratifs ont ete definies : necessite d'une antibiotherapie precoce, bactericide avec un ou plusieurs antibiotiques diffusant dans le parenchyme renal. Le rythme d'administration le plus efficace et le moins toxique peut egalement etre apprecie. Ces donnees experimentales ont d'importantes repercussions pratiques, notamment la recherche de nouvelles attitudes therapeutiques, meme si les correlations avec la pathologie humaine doivent etre effectuees avec une certaine prudence.

Resume Les pyelonephrites experimentales, creees selon plusieurs modeles, fournissent des renseignements interessants sur la physiopathologie et le traitement de ces infections. La reaction inflammatoire initiale, responsable de lesions fibrosantes, peut etre reduite par une antibiotherapie precoce et/ou un traitement anti-inflammatoire. Les phenomenes suppuratifs sont eradiques par les antibiotiques, seuls ou en association, a condition d'etre bactericides, instaures rapidement apres le debut de l'infection. Les amino-glycosides ont l'avantage de s'accumuler dans le parenchyme renal permettant ainsi une attitude preven tive.SAdministres en dose unique, ils sont aussi efficaces et moins toxiques qu'en doses fractionnees. Le traitement des pyelonephrites experimentales permet ainsi d'etablir des schemas therapeutiques rationnels chez l'homme.