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D Talon

Publications and source records attributed to D Talon.

At least 37 records · Page 2Linked to original sources
PubMed2004

[Increased susceptibility to non-beta-lactam antimicrobial agents of MRSA isolates: relationship between genotype and antibiotype].

The objective of our study was to investigate the relationship between molecular epidemiology and antibiotic susceptibility of MRSA during a four-year period. In this aim, we determined the antibiotype of all MRSA identified during a yearly period of 3 months and typed 50 consecutive non-replicate MRSA isolates of each year. We also recorded antibiotic use. Susceptibility rates to gentamicin, tobramycin and ofloxacin remained stable, respectively, 95, 16 and 4%. In contrast, the proportion of MRSA susceptible to erythromycin progressively increased from 7.0% to 32.5% (P < 0.001). PFGE analysis of genomic DNA from the 200 isolates revealed 15 different clones. We identified two epidemic clones, which contained 150 (clone A) and 28 isolates (clone C), respectively. The proportion of isolates belonging to clone A decreased during the study from 86% to 66%. Conversely, clone C increased from 4% to 22%. The increase of erythromycin-susceptibility within MRSA was caused by the emergence of clone C. Non-epidemic strains were more frequently susceptible to ofloxacin (31.8% vs. 1.1%) and tobramycin (45.4% vs. 16.8%) than epidemic strains. Antimicrobial use had not significantly varied during the study. The proportion of beta-lactams, fluoroquinolones, macrolides and aminosides was 71.8, 13.9, 5.0 and 3.8% of the total antibiotic use, respectively. In our hospital, MRSA isolates became more susceptible to antimicrobial of minor use. The selection pressure exerted by beta-lactams and fluoroquinolones was in favor of the spread of strains resistant to these both major antibiotic classes.

Anti-Bacterial Agents↗
PubMed2004

Microbiological and epidemiological studies of Enterococcus faecium resistant to amoxycillin in a university hospital in eastern France.

Over 3 years, during six 1-month periods of surveillance, 69 cases of Enterococcus faecium colonisation or infection were detected in a university hospital in eastern France. Thirty-two cases involved strains resistant to amoxycillin (crude incidence of 0.21/1000 patient-days). The risk of infection with E. faecium was higher if the patient was hospitalised in a haematology ward and/or treated with cephalosporins. Amoxycillin-resistant isolates (AmRE) were isolated from different wards and time periods, and none of the characteristics studied were associated significantly with amoxycillin resistance. Amoxycillin-sensitive and -resistant isolates were characterised by pulsed-field gel electrophoresis. Three epidemic patterns were identified which contained 87.5% (28/32) of the AmRE isolates, indicating that clonal spread was responsible, at least partially, for the high incidence of AmRE in this hospital.

Amoxicillin↗
PubMed2003

Is pulsed-field gel electrophoresis a valuable tool to identify nosocomial cases of Legionella pneumophila disease?

Pulsed-field gel electrophoresis (PFGE) was used to type Legionella pneumophila isolates collected from the water systems of Besançon University Hospital and other hospitals in Franche-Comté region between January 2001 and December 2002 and compare them with patient isolates to identify hospital-acquired pneumonia. Genomic DNA was digested with SfiI and subjected to PFGE in a clamped, homogeneous electric field apparatus. Two of 11 Legionella infections were hospital-acquired. Both were with the same type, also present in the ward water. An environmental strain isolated from the water system of Vesoul Hospital, exhibited DNA pattern 6, also found in three patients with community-acquired pneumonia, who had never been in Vesoul hospital and lived in different towns located >60 km away. Patient 11, who lived in Besançon, was infected with a DNA pattern 12 strain. This patient had never been to the Besançon swimming pool, from which a similar strain was collected. Subtype matching of patient and environmental isolates should be interpreted with caution, and it is important to combine a molecular typing method with sound epidemiological data to ensure that the most stringent criteria are used to determine whether a hospital-reservoir is responsible for nosocomial pneumonia.

Cross Infection↗
PubMed2003

[Long-term usefulness of an information programme on practices in surgical antimicrobial prophylaxis].

INTRODUCTION: In France, numerous concordant studies show that there are some discrepancies between guidelines on surgical antibiotic prophylaxis and the current practice. In a previous study, conducted in April-June 2001, we found that the rate of appropriateness of surgical antimicrobial prophylaxis was approximately 40%. An information programme was implemented and the purpose of this paper was to present the short- and long-term usefulness of this campaign. METHODS: A total of 13 pairs of surgeons/anaesthetists participated in data collection during the three periods of the study. Prescriptions were observed in order to answer to five questions. Five variables describing practices concerning antibiotic prophylaxis in surgery were compared to national recommendations (updated in 1999): did the surgical procedure require antibiotic prophylaxis and was this carried out? Was the antibiotic used appropriate? Was the timing of the first injection optimal? Was the total duration of the treatment correct? Was the dose correct? RESULTS: The overall compliance with recommendations was significantly improved during the third period (P = 0.0002). This improvement was particularly marked for antimicrobial prophylaxis duration. CONCLUSION: It seems that sequential surveillance of antimicrobial prophylaxis, including numerous surgical teams, could considerably improve the practices, if it was associated to informations that allowed physicians to appropriate the procedures.

Antibiotic Prophylaxis↗
PubMed2003

Modelling the usefulness of a dedicated cohort facility to prevent the dissemination of MRSA.

The aim of this retrospective study was to determine whether or not a surgical dedicated cohort facility, mainly dedicated to the care of orthopaedic patients, can control the risk of infection caused by methicillin-resistant Staphylococcus aureus (MRSA). We tested this hypothesis on the orthopaedic surgery ward of a university-affiliated public hospital with 1228 beds by determining whether there was a significant correlation between the colonization pressure exerted by MRSA and the number of cases of acquired MRSA. This was then used as a tool to predict the number of patients contaminated with MRSA in hospitals with and without dedicated cohort facilities. We found that the relative risk of MRSA acquisition increased with the colonization pressure exerted by MRSA imported cases. This statistical model enabled us to predict that the risk of MRSA acquisition would increase by 160% per year in the absence of a dedicated cohort facility. We conclude that these units are useful to control the spread of MRSA in hospitals.

Cohort Studies↗
PubMed2003

[Contribution of antibiotic pressure in the acquisition of methicillin-resistant Staphylococcus aureus (MRSA) in a university hospital].

Methicillin-resistant Staphylococcus aureus (MRSA) is a major nosocomial pathogen, which causes severe morbidity and mortality in hospitals. Antibiotic pressure is recognised as an individual risk factor in the acquisition of MRSA, however, some authors suggest that antibiotic use must be considered as an ecological and collective problem on a unit or hospital scale. The objective of our study was to determine whether antibiotic pressure affects the acquisition of MRSA. The study was conducted during 1 year (from October 2000 to September 2001) at Besançon hospital. The analysis was based on the research of a correlation between incidence of MRSA acquisition, the colonisation pressure exerted by imported MRSA and use of antimicrobials ineffective against MRSA at the unit level. Univariate analysis showed that acquired MRSA cases were significantly correlated with the use of all antimicrobials, as well as with the use of each class of antimicrobial and with colonisation pressure. In multivariate analysis, the stratification of the units into consumer classes allowed us to eliminate the scale effect of each antimicrobial class and to characterise the impact of high antimicrobial use compared to weak antimicrobial. The highest risks of MRSA acquisition were observed for beta-lactams and quinolones. This study shows that "MRSA acquisition" is correlated to antibiotic use and highlights the need to improve antibiotic usage in the control of MRSA.

Cross Infection↗
PubMed2003

[Pseudomonas aeruginosa epidemiology in intensive care units: importance of cross-transmission].

OBJECTIVES: To update the local epidemiological data of Pseudomonas aeruginosa in intensive care units (ICU) by assessing the colonisation incidence rate and the level of cross-transmission. METHODS: Study carried out in both adult ICUs of the university-hospital of Besançon during a 2 years period. Clinical and surveillance specimens were screened for P. aeruginosa. Pulsed-field-gel-electrophoresis was used as genotyping method to evaluate the rate of cross-transmission. RESULTS: During the study, 314 patients were positive for P. aeruginosa (incidence rate of 19.1 patients per 100 admitted patients). One hundred sixty-six of these patients were detected with a clinical specimen and 148 with a screening specimen. Seventy-seven patients were colonised upon admission in the intensive care unit and 237, negative on admission, became positive during their stay. Of the ICU-acquired cases, the mean length of stay before P. aeruginosa colonisation was acquired was 15.7 days. Genotyping revealed that 53.5% of P. aeruginosa colonisation was acquired via cross-transmission (respectively 48.1% in the medical ICU and 59.2% in the surgical ICU); the other cases probably originated from endogenous sources. CONCLUSION: The incidences of P. aeruginosa colonisation upon admission and during hospitalisation are consistent with other french and european studies. Although we probably over-estimated the rate of cross-transmission, our results demonstrate that cross-transmission may be a major cause of P. aeruginosa dissemination in ICUs.

Bacteriological Techniques↗
PubMed2003

Molecular epidemiology of Enterobacteriaceae producing extended-spectrum beta-lactamase in a French university-affiliated hospital.

We conducted a retrospective study to investigate the epidemiology of Enterobacteriaceae producing extended-spectrum beta-lactamase (ESBLE) in our hospital. We determined the occurrence of extended-spectrum beta-lactamase (ESBL) in Enterobacteriaceae over a 2-year period. We also characterised ESBLs by isoelectric focusing (IEF) and investigated the epidemiological relatedness of EBLSE by pulsed field gel electrophoresis (PFGE). During this period, 70 patients were colonised/infected with one or several strains of EBLSE, giving a crude incidence of 0.095 per 1000 patient-days. We found that ESBL-producing Enterobacter aerogenes were the main source of ESBLE dissemination. Indeed, 59.5% of ESBLE were E. aerogenes and 21.9% of the other ESBLE resulted from a plasmid transfer originating from E. aerogenes. IEF and PFGE analysis demonstrated that the dissemination of ESBL from E. aerogenes in our hospital was due to a single clone that always harbours TEM-24. This emphasises the importance of standard contact isolation precautions and the early detection of ESBLE-colonised patients in high risk departments like intensive care units.

DNA, Bacterial↗
PubMed2003

[Transfusion-transmitted bacterial infection: residual risk and perspectives of prevention].

Bacterial contamination of blood components represents today the highest infectious risk of blood transfusion, the risk is particularly high when it affects platelet concentrates. The residual risk of transfusion reaction due to bacterial contamination of platelets concentrates remains stable. For all severity 1 case occurs with 25,000 distributed platelets concentrates and 1 death occurs with 200,000 distributed units. In France, efforts have focused on the prevention of contamination during donation--involving measures such as rejecting the first few millilitres of donated blood and improving skin disinfection--and the prevention of bacterial proliferation in platelets concentrates--notably by removing leukocytes and ensuring high-quality storage of donated blood. Improving strategies for reducing the risks of bacterial contamination is one of the priorities of the French National Blood Transfusion Service (l'Etablissement français du sang-EFS). There is currently considerable debate about the relative importance of bacterial screening methods and methods for inactivating pathogens present in PC. Automated culture (Biomérieux) and the ScanSystem (Hemosystem) and BDS (Pall) method are the most advanced detection systems available, to our knowledge. In term of pathogen inactivation system for platelets, Intercept (Baxter) is nearing the commercial market. These new prevention have logistic and/or functional consequences that will require close scrutiny methods. A national study group is currently considering the consequences of each of these methods and should give its opinion at the end of the first half of 2003.

Bacterial Infections↗
PubMed2002

[Correct and incorrect usage of antibiotics. Prevalence study in Franche-Comté].

OBJECTIVE: To report the results observed regarding the prescription of antibiotics according to various indications in the Franche-Comté area: curative for a community infection, curative for a nosocomial infection and prophylactic. METHOD: A total of 6,038 patients hospitalized in 32 hospital centers of the Franche-comté area were surveyed. RESULTS: Among the 1,016 (16.8% of the total) patients receiving anti-infection products, 47.7% received anti-infection agents for the treatment of a community infection, 25.9% for a nosocomial infection and 26.4% for prophylaxis. Multiple antibiotherapy was more frequent for the treatment of community infections than for nosocomial infections [p = 0.067, Relative Risk = 1.11, (confidence interval: 95%: 1.00-1.24)]. Sixty percent of the prescriptions of 3rd generation cephalosporines were within the community framework. This class of antibiotics was widely prescribed for the treatment of E. coli infections, multi-sensitive to antibiotics, not only before but after bacteriological documentation. Among the 83 patients treated with fluoroquinolone for a nosocomial infection, 47 (56.6%) were treated with monotherapy. Regarding prophylaxis, 3rd generation cephalosporine and fluoroquinolone, which are not indicated for this, were widely used, in contradiction with the recommendations of the Société Française d'Anesthésie et de Réanimation (French Society of Anesthesia and Reanimation). CONCLUSION: This survey, despite the limits related to the prevalence method, shows the high frequency of antibiotic prescriptions that do not conform to the recommendations of the ANDEM (French agency for the assessment of medical practice) and the scientific societies.

Anti-Bacterial Agents↗
PubMed2002

Characterisation of coagulase-negative staphylococci isolated from blood infections: incidence, susceptibility to glycopeptides, and molecular epidemiology.

The purpose of this study was to determine incidence of coagulase-negative staphylococci (CNS) bacteraemia and to characterise the epidemiology of isolates with reduced susceptibility to glycopeptides. CNS isolates from bloodstream infections were collected and characterised by determination of the species, analysis of antibiotic susceptibility, and restriction fragment length polymorphism using pulsed-field gel electrophoresis. The medical records of patients with positive cultures and the trends in glycopeptide use were reviewed to determine the effect of previous antibiotic treatment on the susceptibility profile of these organisms. The incidence of bacteraemia caused by CNS was 0.26 per 100 patients or 0.36 per 1,000 days of hospitalisation. According to genomic fingerprinting typing, 41 (67.2%) cases of bacteraemia were caused by a unique strain of CNS and 20 were caused by several strains. Nineteen of the 61 cases of bacteraemia studied were caused by an isolate with decreased susceptibility to teicoplanin. Genomic DNA analysis of the 90 CNS isolates recovered from the 61 cases of bacteraemia generated 50 unique profiles (1 isolate per major PFGE pattern) and 13 multiple profiles (several isolates per major PFGE pattern). Neither decreased susceptibility of an isolate to teicoplanin nor hospital acquisition was associated with a multiple profile. There was a significant correlation between the incidence of bacteraemia caused by CNS with decreased susceptibility to teicoplanin and glycopeptide use at the unit level but not in individual patients. Cross-transmission did not play an important role in the dissemination of CNS with decreased susceptibility to teicoplanin, thus strains probably become resistant as a result of antibiotic pressure. Prudent use of glycopeptides is necessary to minimise the spread of resistance to these agents.

Adolescent↗
PubMed2002

[Bacteremia caused by coagulase-negative staphylococci: incidence, frequency of teicoplanin resistance and molecular epidemiology].

All the patients hospitalised at Besançon Hospital between October 2000 and December 2000 were included in a prospective study in order to determine the incidence of bloodstream infections caused by coagulase-negative staphylococci (CNS), the prevalence of decreased susceptibility to glycopeptides and the molecular epidemiology of these pathogens. CNS isolates from bloodstream infections were collected and characterised by analysis of antibiotic susceptibility and restriction fragment length polymorphism using pulsed field gel electrophoresis. Forty-five episodes of CNS bacteremia occurred in 43 patients. The crude incidence of infected patients was 0,51 per 1,000 days of hospitalisation. These 45 bacteremia represented 23.3% of the total number of bacteraemia. Forty three of 45 bacteremia were studied, 36 were positive with a single PFGE pattern, 5 bacteraemias with 2 PFGE patterns, and 2 bacteraemias with 3 PFGE patterns. We identified 52 distinct PFGE patterns and 42 major PFGE patterns (35 were isolated in a single patient, 5 in 2 patients and 2 in 3 patients). The dendrogram generated showed deep but limited branching, each large branch corresponding to a species. Of these CNS isolates, 28.8% and 25.0% showed decreased susceptibility to teicoplanin, with the reference method and E-test respectively. The 16 strains belonging to multiple PFGE patterns were not more resistant to teicoplanin. Clonal dissemination did not seem to play a major role in the spread of glycopeptides resistance among CNS.

Adult↗
PubMed2002

[Determination of indicators for non-compliance with guidelines for surgical antimicrobial prophylaxis].

We conducted a prospective study to identify predictors of inappropriateness of surgical prophylaxis. A total of 72 surgeon-anaesthesist pairs participated in data collection. We assessed practices by addressing 5 questions: did the surgical procedure justify the use of antimicrobial prophylaxis, and was it provided? Was the correct agent used? Was the timing of prophylaxis optimal? Was the duration of prophylaxis correct? Was the dose correct? We reviewed 687 procedures, 513 (74.7%) of which were included in the analysis. The proportion of these procedures with totally compliant prescriptions was 41.7%. Of the 156 patients who received an inappropriate drug, 133 (85.3%) received a drug with a broader spectrum than that recommended. Prophylaxis lasted too long in 81 (89.0%) of the 91 patients who received prophylaxis of incorrect duration. Multivariate analysis revealed a clear association between non-compliant prophylaxis and two operation-specific factors: prosthesis implantation (with a relative risk of 2.52) and clean-contaminated operations (with a relative risk of 4.19). More than 50% of patients received inappropriate surgical prophylaxis. Non-observance of guidelines was related to factors that did not influence the infectious potential of the flora.

Adult↗
PubMed2002

[Evaluation of practices in surgical antimicrobial prophylaxis in the Franche-Comté before and after implementation of an information program].

OBJECTIVES: To assess the practices of surgical antimicrobial prophylaxis in the Franche-Comté region of France before and after the implementation of information program. STUDY DESIGN: Prospective multicenter transversal study type before/after. The information program included a feedback on the observed results during the period before and a meeting with opinion leaders. PATIENTS AND METHODS: Data were collected by 28 pairs of surgeons/anaesthetists. Prescriptions were analysed to answer five questions about antibiotic prophylaxis practices in surgery: did the surgical procedure require antibiotic prophylaxis and was this carried out? Was the appropriate antibiotic used? Was the timing of the first injection optimal? Was the total duration of the treatment correct? Was the dose correct? Our data were compared to national recommendations (updated in 1999). RESULTS: The overall frequency of conformity was about 40% both before and after the implementation of an information/awareness campaign. Only the conformity of the total duration of the prophylaxis was significantly higher after the action, but only for interventions that lasted less than two hours. [RR = 2.09 (1.32-3.31), p = 0.001]. This improvement in the total duration of regulation seemed to be related to the more frequent use of written protocols in the surgical units. CONCLUSION: Our study confirms that information campaign have little effect within the framework of the good use of antibiotics. We agree with the experts who claim that only an overall strategy including organization, education and restriction will really improve the frequency of conformity of the practices of surgical prophylaxis.

Anti-Bacterial Agents↗
PubMed2002

Characterization of methicillin-resistant Staphylococcus aureus strains susceptible to tobramycin.

Gentamicin-susceptible, methicillin-resistant, Stapylococcus aureus strains (GS-MRSA) emerged in 1992 in various Parisian hospitals and have subsequently been isolated from all French hospitals. This new GS-MRSA epidemic clone accounted for 50% of MRSA strains in 1996 and for 85% in 2000 in our hospital. We have observed a parallel increase in the prevalence of tobramycin and amikacin-susceptible GS-MRSA (TKS-MRSA). The number of TKS-MRSA strains per 100 MRSA strains has steadily increased from 3.1 in 1996 to 24.0 in 2000. Genotypic characterization of TKS-MRSA strains showed that these strains are a phenotypic variant of the dominant clone of GS-MRSA. To improve our understanding of the changes in methicillin-resistant Staphylococcus aureus (MRSA) susceptibility to non-beta-lactam antibiotics, gentamicin- and amikacin-susceptible MRSA (TKS-MRSA) from our acute-care hospital were compared with TKS-MRSA isolated from a long-term care hospital located in another region of France. The nature of the care facility did not seem to play a major role in the hospital dissemination of TKS-MRSA. We also found that changes in antibiotic use alone do not account for the emergence of these strains.

Anti-Bacterial Agents↗
PubMed2002

The impact of resistance to methicillin in Staphylococcus aureus bacteremia on mortality.

Background: It is unclear whether methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) differ in virulence. We therefore carried out a prospective study of cases of S. aureus bacteremia over a period of 2 years at our university hospital. We report herein the results of a comparative analysis of the clinical characteristics and mortality rates associated with cases of bacteremia caused by MRSA and MSSA. Methods: Over a 2-year period, we reviewed the medical records of hospitalized patients with blood cultures positive for S. aureus. Demographic characteristics, underlying diseases, diagnosis, clinical features, severity, laboratory findings, antimicrobial treatment, and resistance to methicillin were analyzed as possible risk factors for death attributed to bacteremia. Results: The rate of mortality attributed to bacteremia was 27.3% (27 patients): 13 (43.3%) deaths were recorded for patients infected with MRSA and 14 (20.3%) for patients infected with MSSA (P=0.0339, OR=3.00 (1.08--8.46)). Two variables were significantly associated with death within 14 days of the onset of bacteremia in univariate and multivariate analyses after adjusting for antimicrobial treatment: malignant hematologic disease (protective factor; OR=0.184 (0.038--0.882)) and resistance to methicillin (risk factor; OR=2.97 (1.12--7.88)). Conclusion: This study shows that S. aureus bacteremia has a high mortality rate, especially if the strain involved is methicillin-resistant, regardless of patient age and the efficacy of antimicrobial treatment.

Journal Article↗