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Daniel Talon

Publications and source records attributed to Daniel Talon.

At least 19 recordsLinked to original sources
PubMed2006

Effect of individual- and group-level antibiotic exposure on MRSA isolation: a multilevel analysis.

OBJECTIVES: To observe the relative role of individual and group-level antimicrobial selective pressure on subsequent methicillin-resistant Staphylococcus aureus (MRSA) isolation in a university hospital. METHODS: For this purpose, 18 596 patients were included in a retrospective statistical analysis, applying multilevel modelling with discrete time intervals at the lowest level. Individual-level and hospital group variables on antimicrobial exposure and MRSA colonization pressure were collected from computerized databases. RESULTS: The simultaneous hospital group- and individual-level analysis showed individual exposure to fluoroquinolones and collective exposure to penicillins to be associated with MRSA isolation after adjustment for colonization pressure and other potential confounders. CONCLUSIONS: These results support efforts to reduce prescriptions of selected antimicrobial drug classes such as fluoroquinolones and show the added value of multilevel analysis for research on the adverse outcomes of antibiotic prescribing.

Aged↗
PubMed2006

Discrepancies between prescribed daily doses and WHO defined daily doses of antibacterials at a university hospital.

AIMS: The defined daily doses (DDD) defined by the WHO are widely used as an indicator to measure antibiotic use in the hospital setting. However, discrepancies exist between countries in terms of antibiotic dosage. The aim of the present study was to compare, for each antibacterial agent available at our university hospital, the prescribed daily doses (PDD) with the DDD. METHODS: Data were extracted from the pharmacy computer system. Antibiotic use was expressed in DDD per 1000 patient days. We also calculated the ratio of number of DDD:number of treatment-days and estimated the average PDD for each antibiotic and route of administration. RESULTS: The average PDD did not correspond to the DDD for many classes of antibiotics. If fluoroquinolones and cephalosporins were prescribed at a dosage close to the DDD, other antimicrobial classes such as penicillins, aminoglycosides or macrolides were not. Overall, the number of DDD overestimated the number of treatment days by 40%. For the most consumed antibiotic at our hospital, i.e. oral amoxicillin-clavulanic acid, the PDD was three times the DDD. CONCLUSIONS: Our study shows that, except for the fluoroquinolones and the cephalosporins, the number of DDD did not correctly reflect the number of antibiotic treatment days at our hospital. This does not invalidate the systematic approach of the WHO and hospitals should use the DDDs to make national and international comparisons of their antibiotic use. However, each hospital should define and validate its own indicators to describe the local exposures to antibiotics and to study the relationship with resistance.

Anti-Bacterial Agents↗
PubMed2006

[Air cleanliness in operating rooms: on-site controls and biological testing].

Air cleanliness control in operating rooms is based on air filtration, and targets the lowest density of particules and bacteria. Legally, the equipment must be periodically verified during periods of inactivity. Most airborne bacteria are of human origin. There is no fixed ratio between the particle count and the level of bacterial contamination. A study of different types of operating room at Besançon Medical Center reached the following conclusions:--Controls are also required during periods of activity.--Bacteriological testing is crucial.--Unidirectional airflow, especially of the horizontal type, is superior to other forms of isolation. The authors propose a "Functionality index", calculated as follows: bacterial count during use of the room minus bacterial count during non use/the number of people in the room. Efficient equipment would have a low index, which would be unmodified by the number of persons present.

Air Microbiology↗
PubMed2005

Use of intranasal mupirocin to prevent methicillin-resistant Staphylococcus aureus infection in intensive care units.

INTRODUCTION: Methicillin-resistant Staphylococcus aureus (MRSA) causes severe morbidity and mortality in intensive care units (ICUs) worldwide. The purpose of this study was to determine whether intranasal mupirocin prophylaxis is useful to prevent ICU-acquired infections with MRSA. MATERIALS AND METHODS: We conducted a 4-year observational retrospective study in a 15-bed adult medical ICU. During the first 2-year period mupirocin ointment was included in the MRSA control programme; during the second, mupirocin was not used. The main endpoint was the number of endogenous ICU-acquired infections with MRSA. RESULTS: The number of endogenous acquired infections was significantly higher during the second period than during the first (11 versus 1; P = 0.02), although there was no significant difference in the total number of patients infected with MRSA between the two periods. We also observed that nasal MRSA decolonisation was significantly higher in the mupirocin period than in mupirocin-free period (P = 0.002). CONCLUSION: Our findings suggest that intranasal mupirocin can prevent endogenous acquired MRSA infection in an ICU. Further double-blind, randomised, placebo-controlled studies are needed to demonstrate its cost-effectiveness and its impact on resistance.

Administration, Intranasal↗
PubMed2004

Methodological validation of monitoring indicators of antibiotics use in hospitals.

BACKGROUND: For several years now, the French national recommendations have been trying to set up a surveillance system in hospitals to link data on antibiotic resistance and data on the use of antibiotics, particularly for certain 'micro-organism/antibiotic' pairs. The indicators recommended in the lastest newsletter of the Direction Générale de la Santé (French Public Health Department) for monitoring the consumption of antibiotics were the number of days of treatment or the number of defined daily doses (DDD), both (in)directly related to the number of days of hospitalisation and/or the number of patients hospitalised. OBJECTIVE: The aim of this study was to compare the actual number of days of treatment, which is an observed indicator, with two indicators calculated on the basis of the DDD and the DPD (daily prescribed dose), both in terms of feasibility of collection and the relevance of the information generated. MATERIALS AND METHODS: For several hospital care units, the 'length of exposure' to a given antibiotic was determined by four different indicators: two actual observed indicators [the patient's medical file (reference) and the named-patient based, computerised dispensing system from the central pharmacy] and two derived calculated indicators [obtained by dividing the number of grams prescribed by the DDD or by the DPD]. RESULTS: The average incidence density of antibiotic treatment (length of exposure per 1000 days of hospitalisation) obtained by the calculated indicators was higher than that obtained with the observed reference (+52% for the DDD and +33% for the DPD) but lower than that obtained with the second observed indicator (computerised system) (-10%). The differences were large and random (high variability depending on the hospital department, the antibiotic and the administration route; variations in both directions: actual length of treatment longer or shorter than the calculated length of treatment). CONCLUSION: The question which indicator should be chosen is inconclusive for the evaluation of the selection pressure exerted by an antibiotic. The two indicators proposed in the newsletter (observed indicator and calculated indicator) seem to be complementary for use in a regional or national network to monitor resistance and consumption of antibiotics. Each hospital should validate the indicators and define for itself which indicator is most appropriate for estimating the actual length of antibiotic exposure. This may imply different indicators for different units, antibiotics or even administration routes within one particular hospital setting. Once validated the hospital has a powerful tool generating data that can be linked to resistance data.

Anti-Bacterial Agents↗
PubMed2004

Control of Enterobacteriaceae producing extended-spectrum beta-lactamase in intensive care units: rectal screening may not be needed in non-epidemic situations.

OBJECTIVE: To evaluate the usefulness of screening cultures in the control of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae in intensive care units (ICUs). DESIGN: A 4-year retrospective study. SETTING: Two adult ICUs of a university-affiliated public hospital in France. RESULTS: A total of 7,777 specimens were analyzed and 28 (0.97%) of 2,883 screened patients had a positive result on a screening test, among the 3,678 admitted patients. Thirteen of these 28 patients were only carriers; 4 were carriers and then were colonized or infected 2, 2, 3, and 8 days later, respectively; and 11 were colonized or infected before a screening test was positive. Cluster analysis showed that the occurrence of ESBL-producing Enterobacteriaceae cross-transmission within both ICUs was limited to 9 cases. Thus, most cases (19 of 28) were probably imported. Surveillance cultures failed to detect 9 of the 19 cases. CONCLUSION: The low prevalence of ESBL-producing Enterobacteriaceae carriers on admission (0.45%) and the relative ineffectiveness of our screening test to detect imported cases suggest that systematic detection of ESBL-producing Enterobacteriaceae in ICU patients is not cost-effective and that the use of clinical cultures may be sufficient to control ESBL-producing Enterobacteriaceae in non-epidemic situations.

Adult↗
PubMed2004

[Prophylactic antibiotics in urological surgery: compliance of prescriptions in Franche-Comté with national guidelines].

STUDY OBJECTIVE: To evaluate prophylactic antibiotic practices in urological surgery in Franche-Comté. MATERIAL AND METHODS: Six urological surgery teams participated in data collection. Practices were evaluated in comparison with national guidelines by means of five questions: Did the surgical operation justify prophylactic antibiotics and was this treatment administered? Was the antibiotic selected that recommended by national guidelines? Was the total duration appropriate? Was the time of the first injection appropriate? Was the dosage appropriate? The Société Française d'Anesthésie et de Réanimation (SFAR) guidelines, revised in 1999, constituted the reference. RESULTS: Of the 213 operations included in the study, 134 corresponded to Altemeier class 1 and 2 operations for which the SFAR has issued guidelines. The overall compliance rate was 22.6%. Among the 56 patients who did not receive the recommended molecule, 45 received a molecule with a broader spectrum of activity than that of the recommended molecule. The duration of prophylactic antibiotics was longer for 10 of the 11 patients in whom the duration of prophylaxis did not comply with guidelines. Finally, for more than one third of operations, the time of injection of the first dose was not optimal. CONCLUSION: This study demonstrated the high frequency of non-compliance with prophylactic antibiotic prescription guidelines in urological surgery in Franche-Comté. These guidelines must be reinforced and applied to ensure the efficacy of prophylactic antibiotics and to avoid the emergence of resistant strains.

Antibiotic Prophylaxis↗
PubMed2003

Methicillin-resistant Staphylococcus aureus (MRSA) in rehabilitation and chronic-care-facilities: what is the best strategy?

BACKGROUND: The risk associated with methicillin-resistant Staphylococcus aureus (MRSA) has been decreasing for several years in intensive care departments, but is now increasing in rehabilitation and chronic-care-facilities (R-CCF). The aim of this study was to use published data and our own experience to discuss the roles of screening for MRSA carriers, the type of isolation to be implemented and the efficiency of chemical decolonization. DISCUSSION: Screening identifies over 90% of patients colonised with MRSA upon admission to R-CCF versus only 50% for intensive care units. Only totally dependent patients acquire MRSA. Thus, strict geographical isolation, as opposed to "social reinsertion", is clearly of no value. However, this should not lead to the abandoning of isolation, which remains essential during the administration of care. The use of chemicals to decolonize the nose and healthy skin appeared to be of some value and the application of this procedure could make technical isolation unnecessary in a non-negligible proportion of cases. SUMMARY: Given the increase in morbidity associated with MRSA observed in numerous hospitals, the emergence of a community-acquired disease associated with these strains and the evolution of glycopeptide-resistant strains, the voluntary application of a strategy combining screening, technical isolation and chemical decolonization in R-CCF appears to be an urgent matter of priority.

Journal Article↗
PubMed2003

Bacterial contamination of a cornea tissue bank: implications for the safety of graft engineering.

PURPOSE: To analyze the difficulties involved in managing an episode of bacterial contamination in a cornea bank. We describe (1) the circumstances of bacterial contamination discovery, (2) the methods used to investigate the outbreak, (3) the corrective measures adopted, and (4) the method introduced to improve the reaction capacity in case of bacterial contamination. METHODS: All the samples collected were cultured in an attempt to identify the environmental reservoir of the contaminated epidemic clone. Bacteria were identified by Gram stain, oxidase test, and biochemical characteristics. The clonality of the strains was assessed by pulsed-field gel electrophoresis. RESULTS: The bacterial contamination was confirmed for 28 corneas, and 70 additional corneas were discarded. The source of the contamination was identified 17 days after the beginning of the episode. It consisted of a clonal bacterial strain that was found in trypan blue, the dye, used to examine all the tissues. The contaminating bacterium was Burkholderia cepacia, a well-known nosocomial pathogen. A total of 169 grafted corneas had been checked with the contaminated reagent. No cases of post-graft infection were recorded. CONCLUSION: Trypan blue played a major role in this outbreak. The mode and chronology of contamination remain unresolved. This exceptional event emphasizes the risk of bacterial contamination in tissue/cell banks, the necessity to improve methods for its prevention, and procedures to limit its consequences.

Burkholderia Infections↗
PubMed2003

Relationship between molecular epidemiology and antibiotic susceptibility of methicillin-resistant Staphylococcus aureus (MRSA) in a French teaching hospital.

The objective of this study was to investigate the relationship between molecular epidemiology and antibiotic susceptibility of methicillin-resistant Staphylococcus aureus (MRSA) over a period of 4 years. The antibiotype of all MRSA isolates that were identified during a yearly period of 3 months was determined; 50 consecutive non-replicate MRSA isolates were typed each year. Susceptibility rates to gentamicin, tobramycin and ofloxacin remained stable (95, 16 and 4 %, respectively). In contrast, the proportion of MRSA isolates susceptible to erythromycin increased progressively from 10.5 to 32.5 % (P < 0.001). PFGE analysis of genomic DNA from 200 isolates revealed the presence of 15 different clones. Two epidemic clones were identified, which contained 150 (clone A) and 28 (clone C) isolates. Non-epidemic strains were more frequently susceptible to ofloxacin (31.8 versus 1.1 %) and tobramycin (45.4 versus 16.8 %) than epidemic strains; those isolates that were susceptible to all antibiotics tested belonged to sporadic clones. The increase of erythromycin susceptibility within MRSA isolates was caused by the emergence of clone C. This study suggests that when selection pressure exerted by an antibiotic is insufficient (i.e. below a threshold level), fitness advantages play a predominant role in the dissemination of MRSA clones. The balance between the selection pressure exerted by antibiotics and the disadvantage of lower replication rates of resistant strains in the absence of antibiotics complicates the biological model of clonal dissemination of epidemic MRSA strains.

Anti-Bacterial Agents↗
PubMed2003

Genetic and phenotypic variations of a resistant Pseudomonas aeruginosa epidemic clone.

From May 1997 to December 2001, a serotype O:6 multidrug-resistant strain of Pseudomonas aeruginosa colonized or infected 201 patients in the University Hospital of Besançon (France). The susceptibility profile of this epidemic clone to fluoroquinolones and aminoglycosides was relatively stable during the outbreak but showed important isolate-to-isolate variations (up to 64-fold) in the MICs of beta-lactams. Analysis of 18 genotypically related isolates selected on a quarterly basis demonstrated alterations in the two DNA topoisomerases II and IV (Thr83-->Ile in GyrA and Ser87-->Leu in ParC) and production of an ANT(2")-I enzyme. Although constitutively overproduced in these bacteria, the MexXY efflux system did not appear to contribute significantly to aminoglycoside resistance. beta-Lactam resistance was associated with derepression of intrinsic AmpC beta-lactamase (with isolate-to-isolate variations of up to 58-fold) and sporadic deficiency in a 46-kDa protein identified as the carbapenem-selective porin OprD. Of the 18 isolates, 14 were also found to overproduce the efflux system MexAB-OprM as a result of alteration of the repressor protein MexR (His107-->Pro). However, complementation experiments with the cloned mexR gene demonstrated that MexAB-OprM contributed only marginally to beta-lactam and fluoroquinolone resistance. Of the four isolates exhibiting wild-type MexAB-OprM expression despite the MexR alteration, two appeared to harbor secondary mutations in the mexA-mexR intergenic region and one harbored secondary mutations in the putative ribosome binding site located upstream of the mexAB oprM operon. In conclusion, this study shows that many mechanisms were involved in the multiresistance phenotype of this highly epidemic strain of P. aeruginosa. Our results also demonstrate that the clone sporadically underwent substantial genetic and phenotypic variations during the course of the outbreak, perhaps in relation to local or individual selective drug pressures.

Aminoglycosides↗
PubMed2003

[The importance of isolating septic patients in an autonomous unit in orthopedic surgery and traumatology].

UNLABELLED: To examine whether Sepsis Containment Units are presently in use by French Orthopedic surgeons in a number of hospitals and the subsequent efficacy of these measures in the prevention of risks linked to methicillin resistant Staphylococcus aureus (MRSA), MRSA was used as an example because it is the bacteria most frequently associated with infection in orthopedics. The transient carriage of MRSA on the hands of hospital personnel is the most common mechanism of patient to patient transmission. Consequently, the incidence of nosocomial MRSA in patients can be used to assess the quality of infection control. SETTING: The orthopaedic surgery department (104 beds) of a 1. 228 bed, university affiliated public hospital located in eastern France (Besançon). METHODS: First: a questionnaire was sent out to 71 French university orthopedic departments to investigate the practice in place. Second: to establish whether a significant correlation exists between the colonisation pressure exerted by real imported MRSA, and the number of cases of real acquired MRSA since we know that colonisation pressure of bacteria is a major factor in the prognosis of clinical infection. Third: our orthopedic surgery department was redesigned to study the risks of colonisation pressure with or without Sepsis Containment Units. RESULTS: First: among the 71 orthopedic departments studied, only 11 used a Sepsis Containment Unit. Second: there is a definite, linear relationship between the colonisation pressure exerted in a unit by real imported MRSA and the number of cases of real acquired clinical infection. Third: in the absence of Sepsis Containment Units, the risk of MRSA infections is increased by 160%. Debat: the classical clinical arguments concerning the dangers of hand or aerobic MRSA transmission are confirmed by our figures. The strict use of Sepsis Containment Units prevents contamination of septics by septics. Inversely, the rigorous concentration of means in the Sepsis Containment Units also prevents cross contamination of septics. At question are the psychological and financial inconveniences of Sepsis Containment Units. The results of this experiment, performed in orthopedic surgery, show that the use of Sepsis Containment Units is just as critical in other surgical units: vascular, thoracic, etc., nor should they be overlooked in outpatient and emergency care--often the first step in orthopedic surgery. CONCLUSION: Sepsis Containment Units are essential and merit further development.

Containment of Biohazards↗
PubMed1999

Clinical and molecular epidemiology of hospital Enterococcus faecalis isolates in eastern France.

OBJECTIVE: To report on the occurrence of Enterococcus faecalis hospital isolates obtained during 1 year in hospitals in the Franche-Comté region of France. METHODS: Clinical isolates of E. faecalis of different antibiotic susceptibility phenotypes from hospitalized patients were characterized by pulsed-field gel electrophoresis. Patients with positive cultures were investigated by three case-control studies to identify risk factors for colonization/infection. RESULTS: The crude incidence of colonization/infection was 2.37%, and 4-day and 7-day colonization rates after admission were 10.0% and 6.36%, respectively. The rates of high-level resistance to kanamycin (HLKR) and to gentamicin (HLGR) were 47.1% and 7.1%, respectively. No isolate was resistant to glycopeptides or produced beta-lactamase. The 209 hospital isolates obtained during the study yielded 98 major DNA patterns, of which two were major epidemic patterns including HLKR isolates. No single factor was significantly associated with colonization/infection by HLKR isolates. The length of hospitalization before isolation was associated with colonization by HLGR isolates. CONCLUSIONS: The isolation frequency of E. faecalis strains with acquired resistance to aminoglycoside antibiotics, and the wide dissemination of resistant strains with characteristics that allow them to persist and spread, argue for further large prospective surveys of clinical isolates of E. faecalis in hospitals.

Journal Article↗