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F Eb

Publications and source records attributed to F Eb.

At least 19 recordsLinked to original sources

[Performance of different methods of oxacillin resistance detection in atypic strains of Staphylococcus aureus].

Seventy-three of aminoglycoside-susceptible methicillin-resistant Staphylococcus aureus (AS-MRSA) and 12 kanamycin-tobramycin-resistant methicillin-susceptible S. aureus (KTR-MSSA) isolates were phenotypically and genotypically examined for methicillin susceptibility. The AS-MRSA profile represents 8.3% of MRSA strains and the KTR-MSSA profile represents 1.38% of MSSA strains. The diffusion method using the 5 microg oxacillin and 30 microg cefoxitin discs on Mueller-Hinton Agar (MHA) with and without NaCl, the incubation at 35 degrees C or 30 degrees C for 24 or 48 hours respectively, and the determining oxacillin MICs by E-test (AES, Combourg, France) were performed and used as phenotypic methods. We also used the mecA gene PCR which was considered as the "gold standard" for methicillin resistance detection, and the Slidex MRSA Detection (bioMérieux) that detect the presence of mecA gene product (PBP 2a). To increase the level of PBP 2a expression, the 30 microg cefoxitin disc was used as an inducer. All the AS-MRSA strains (100%) were detected by the cefoxitin disc in all conditions and by the oxacillin disc on MHA with 2% of NaCl at 35 degrees C. Without NaCl, the sensitivity fell to 97,2% by oxacillin disc. The oxacillin MICs for these isolates ranged from 2 to 128 mg/l. The mecA gene determinant and its product PBP 2a were detected in all AS-MRSA strains. All KTR-MSSA strains were phenotypically methicillin-susceptible and oxacillin MICs were below or borderline of breakpoint (< or =2 mg/l). The mecA gene determinant and its product were detected in one strain which was considered to be the most heterogeneous of those tested.

Anti-Bacterial Agents↗

[Extended-spectrum betalactamases producing Escherichia coli: a new health-care associated infection threat?].

OBJECTIVES: Study the health-care associated infection risk due to Extended-Spectrum Betalactamases Producing Escherichia coli (ESBL Esc) isolated from diagnostic samples. METHODS: Descriptive, longitudinal and prospective study of 104 diagnostic isolates of ESBL Esc, one per patient, identified in Amiens university hospital between February 1999 and December 2005. Patients (sex, age, contamination risk factor, antecedent hospitalization) and microbiological data were progressively collected, entered into EPI INFO 6.04dFr software (ENSP, France) database, and compared using the chi-square test and Wilcoxon rank sum test, as appropriate. A p value of less than 0.05 was considered significant. RESULTS: Diagnostic ESBL Esc isolates raised, per 1000 isolates of Esc, from 1.2 in 1999 to 6 in 2005. Global and acquired isolates number of ESBL Esc varied from 7 and 3 in 2002 to 25 and 19 in 2003 (P=0.22). ESBL Esc global and acquired incidence per 10(5) patient-days were, 0.8 and 0.6 in 1999 and 4.99 and 3.4 in 2005 (P<10(-6)), but rose from 0.6 acquired isolate in 2002 to 3.9 in 2003 (P=0.002). ESBL Esc, isolated from urines, stools, pulmonary, blood and surgical site samples of patients of>/=65 years aged (68.3%), were imipenem and latamoxef sensitive. Their acquisition risk factors found were hospitalization during the last 6 month period (40/104) and transfer from other institutions (20/104). CONCLUSION: ESBL Esc isolates, among ESBL-producing Enterobacteriaceae, constitute an escalating health-care associated risk in our institution. The research at admission time of ESBL-producing Enterobacteriaceae, mainly in acute geriatric wards, strict isolation precaution and hand hygiene observance, rational antibiotic usage, are the key actions to control their cross transmission. Nonetheless, other studies are needed to determine whether we are in front of an ESBL Esc new clone emergence.

Escherichia coli↗

Detection of methicillin/oxacillin resistance and typing in aminoglycoside-susceptible methicillin-resistant and kanamycin-tobramycin-resistant methicillin-susceptible Staphylococcus aureus.

Eighty-five atypical isolates of Staphylococcus aureus divided into 73 aminoglycoside-susceptible methicillinresistant (AS-MRSA) and 12 kanamycin-tobramycin-resistant methicillin-susceptible (KTR-MSSA) were phenotypically and genotypically examined for methicillin resistance. Among these tests, the diffusion method using the oxacillin and cefoxitin disks on Mueller-Hinton agar with and without NaCl, the incubation at 35 degrees C or 30 degrees C for 24 or 48 hr, respectively, and the determination of oxacillin MICs by E-test were performed. We also examined the presence of the mecA gene by PCR and its product PBP 2a by the Slidex MRSA Detection test after induction by cefoxitin disk. All of the AS-MRSA strains (100%) were detected by the cefoxitin disk in all conditions and by the oxacillin disk on Mueller-Hinton agar with 2% of NaCl at 35 degrees C. Without NaCl, the sensitivity fell to 97.2% by oxacillin disk. The oxacillin MICs for these isolates ranged from 2 to 128 mg/L. The mecA gene determinant and its product PBP 2a were detected in all AS-MRSA strains. All KTR-MSSA strains were phenotypically methicillin-susceptible and oxacillin MICs were below or borderline of breakpoint (< or =2 mg/L). The mecA gene determinant and its product were detected in one strain. Pulsed-field gel electrophoresis (PFGE) was applied and revealed the presence of two major patterns A (36.9%) and B (46.2%) in AS-MRSA isolates and seven patterns in the KTR-MSSA strains.

Aminoglycosides↗

Community-acquired bacteraemic pneumococcal pneumonia in adults: effect of diminished penicillin susceptibility on clinical outcome.

Pneumococcal pneumonia remains a common disease with a high mortality rate. Between 1995 and 2000, we prospectively analyzed 95 consecutive adult cases of community-acquired bacteraemic pneumococcal pneumonia treated in a single centre. The incidence of pneumococcal resistance to penicillin increased from 19 to 50% during the study period. Multivariate analysis showed that only age and recent hospitalization were independently associated with fatal outcome. The proportion of penicillin-resistant strains was slightly but not significantly higher among patients who died before the fourth hospital day than among those who died later. Patients who died before D4 were more likely to have a recent history of hospitalization, cancer and/or chemotherapy. It thus appears that infection by a resistant pneumococcal strain is not in itself a gravity factor in this setting, but that their acquisition is associated with pejorative clinical features.

Adult↗

Molecular diversity of Proteus mirabilis isolates producing extended-spectrum beta-lactamases in a French university hospital.

Between February 1997 and December 2002, 3340 hospitalised patients yielded samples positive for Proteus mirabilis, of whom 45 (1.3%) were colonised/infected by P. mirabilis producing extended-spectrum beta-lactamases (ESBLs). The gross incidence of patients colonised/infected by ESBL-producing P. mirabilis was 1.61/10(5) days of hospitalisation, with 20% of isolates being collected from patients in urology wards, most frequently (53.3%) from urine samples. Seventeen (37.7%) of the 43 isolates were obtained from samples collected within 48 h of hospitalisation, indicating that they were community-acquired. Isoelectric focusing assays and sequencing identified the TEM-24, TEM-92 and TEM-52 ESBLs. Pulsed-field gel electrophoresis revealed eight pulsotypes (I-VIII), with the two most common pulsotypes, IV and VI, comprising ten (23.3%) and 12 (26.6%) isolates, respectively. These pulsotypes were considered to represent epidemic strains and spread in various wards of the hospital.

Anti-Bacterial Agents↗

[Chlamydia trachomatis urogenital infections in women. Best diagnostic approaches].

Chlamydiae are obligate intracellular bacteria. Chlamydia trachomatis is the most common sexually transmitted disease (STD). The C. trachomatis damaging disease sequelae such as sterility is based on intense and chronic inflammation elicited and maintained by reinfection or persistent infection. The high prevalence of C. trachomatis infection reflects the long and successful adaptation of these organisms to persist in their human host population. The large group of asymptomatically infected persons is not only at risk of serious long-term sequelae but also sustains transmission within communities. C. trachomatis acute infections have been diagnosed by cell culture, direct immunofluorescence, enzyme immunoassay, direct DNA hybridization, and more recently by nucleic acid amplification tests (NAATs). In chronic or persistent chlamydial infections, the level of Chlamydia is very low and bacteria are often not viable. Such infections would be characterized by continuing positive NAATs but only intermittent isolation of viable Chlamydia and positive assays for chlamydial protein antigen. The development of NAATs has been a major advance in the field of chlamydial diagnosis. The use of NAATs associated with serology test is the best diagnosis. The introduction of assays based on amplification of genetic material has subsequently increased the sensitivity of detecting chlamydial infections and offers the opportunity to use non-invasive sampling techniques to screen for infections in asymptomatic subjects. In this article, it was proposed the best diagnosis approaches for detection of acute and chronic infections.

Acute Disease↗

[Case control study of extended-spectrum betalactamase producing Serratia marcescens outbreak in a paediatric intensive care unit].

OBJECTIVES: To identify patient-related risk factors of infection and ways of transmission of extended-spectrum betalactamase (ESBL) producing Serratia marcescens in the paediatric intensive care unit (PICU) of Amiens university hospital (France) between June and July 2002. METHODS: Five cases (four pulmonary infected and one stool contaminated symptom-free neonates) and 35 controls, admitted in the PICU, are included. S. marcescens ESBL analysed are isolated from respiratory tract and faecal samples for cases and urine and pus samples from two non-paediatric other patients. Univariate and multivariate analysis are performed on EPI INFO 6.04 dFr and SPSS 11.0.1. RESULTS: S. marcescens ESBL infections or colonisations rate is 12.5% [4.7-27.6]. The incidence is 8.8 [6.7-11.6] per 1000 hospital-stay days. By univariate analysis, cases and controls don't differ with respect of age, sex, and weight at admission or preterm delivery. Cases don't have more often invasive nursing care than controls. But, they were intubated (P <0.03) and hospitalised (P <0.03) for a longer time than controls. Linear regression analysis showed that duration of intubation was independent predictor of acquisition of S. marcescens ESBL (P <0.008). S. marcescens ESBL strains implicated in pulmonary infections, showed the same pattern of multidrug resistant and ERIC-PCR profile. This clone differs from others isolated from stool or other samples from other hospital wards. CONCLUSION: As S. marcescens cross-colonization appears to be due to lake of hand hygiene and asepsis during invasive nursing care, reinforcing hygiene measures permit to contain the outbreak.

Adolescent↗

Chlamydia pneumoniae, but not Bartonella quintana, is associated with coronary heart disease: results of a French case-control study.

Serologic cross-reactivity has been demonstrated between Bartonella quintana and Chlamydia pneumoniae. Therefore, the association between antibodies to C. pneumoniae and coronary heart disease (CHD) as described in the literature may be due to antibodies cross-reacting with B. quintana. To investigate this hypothesis, we evaluated, in a case-control study, the prevalence of C. pneumoniae and B. quintana antibodies among 296 cases with angiographically significant artery lesions and 170 controls without angiographically demonstrable coronary artery disease. The prevalence of C. pneumoniae antibodies was higher among cases than among controls: 69% versus 49% (P < 0.001; OR 1.39; 95% CI (1.55; 3.52)). Multiple logistic regression demonstrated that C. pneumoniae seropositivity is an independent risk factor for CHD (adjusted OR 2.31; 95% CI (1.49; 3.60)). No statistically significant association was demonstrated between B. quintana seropositivity and CHD. Antibodies to both C. pneumoniae and B. quintana were found in nine subjects (seven cases and two controls), suggesting co-infection rather than cross-reactivity.

Bartonella quintana↗

Regional dissemination of Salmonella enterica serovar Enteritidis is season dependent.

OBJECTIVE: To carry out epidemiological typing of clinical isolates of Salmonella enterica serovar Enteritidis by pulsed-field gel electrophoresis (PFGE), random amplified polymorphic DNA (RAPD) and analysis of their antibiotic resistance. METHODS: Over a 12-month period, 44 Salmonella Enteritidis isolates, recovered from 40 patients admitted to the University Hospital Center of Amiens, France and from three outpatients, were characterized by the analysis of phenotypic and genotypic traits and clinical data from medical reports. RESULTS: Forty nontyphoidal salmonellosis episodes were diagnosed in hospitalized patients (34 episodes of gastroenteritis, two episodes of bacteremia not affecting other organs, one episodes of bacteremia plus urinary infection, one episodes of bacteremia plus gastroenteritis, one episodes of chronic colitis plus gastroenteritis and one episode of peritonitis), and three carriers were observed in outpatients. By means of PFGE, RAPD and antibiotic susceptibility patterns 44 isolates were subdivided into 16 clonally related groups. Two of them were predominantly implicated in the course of these infections, being responsible for two successive waves of infection, while the others were encountered sporadically.

Adolescent↗

[Evaluation of the efficacy of a multiresistant bacteria control programme in a teaching hospital, studying the evolution of methicillin-resistant Staphylococcus aureus incidence].

Methicillin-resistant Staphylococcus aureus (MRSA) constitute the most important multiresistant bacteria (MRB) recovered in French hospitals. Our objective was to measure these MRSA diffusion in our hospital to evaluate the MRB control programme which had been implemented in the beginning of 1999. This study was conducted in a teaching hospital containing 1800 beds, from February 1999 to January 2001. All MRSA isolated in clinical samples were included. Duplicates (same bacteria in the same patient) were excluded. The detection of methicillin-resistance was performed at 30 degrees C, by disk diffusion method. Incidence densities were determined with their 95% confidence interval (CI 95%). Their evolution by four-month period was evaluated with the chi-square test for trend. During the two-year period, 866 MRSA were isolated. The global incidence was 0,88 per 1000 patient-days (PD) (IC 95% = left open bracket 0,83-0,93 right open bracket ). For cases acquired in our hospital the incidence was 0,66 per 1000 PD, whereas it was 0,26 per 1000 PD for imported cases. Concerning the evolution of incidences, no significant trend was observed for global incidence. The incidence of acquired MRSA decreased during the first year, but increased thereafter. The incidence of imported MRSA increased with a significant trend (p < 10(-5)). The number of these imported MRSA isolated in our hospital was twice fold higher in 2000. This study emphasizes an important actual problem : the increase of patient colonization pressure at the time of admission in hospitals. This increase, which can be due in part to a community transmission, is responsible for a reduction of the efficacy of MRSA control programmes.

Chi-Square Distribution↗

Prevalence of methicillin-resistant Staphylococcus aureus carriage at the time of admission in two acute geriatric wards.

Studies on methicillin-resistant Staphylococcus aureus (MRSA) in the elderly have been concerned with patients hospitalized in nursing homes or long-term care facilities. Our objective was to estimate the prevalence of MRSA at the time of admission in two acute geriatric wards with high endemic MRSA incidence in a French teaching hospital. A prospective screening of MRSA carriers was conducted by swabbing nares and wounds during five weeks for all patients on the day of admission. For each patient demographic, administrative, clinical and therapeutic data were recorded. Their associations with MRSA carriage were studied by logistic regression analysis. On the day of admission, 35 patients (14.6%) were MRSA carriers. Variables independently associated with carriage were hospitalization within the six last months (OR = 4.64; P < 0.001) and the existence of wounds or bedsores (OR = 2.864; P = 0.02). The high prevalence of MRSA carriage at the time of admission could explain in part the high incidence of MRSA in these wards. A systematic selective screening targeted on patients with high risk of carriage should be helpful to implement barrier precautions and reduce cross-transmission.

Aged↗

Surveillance of methicillin-resistant Staphylococcus aureus (MRSA) and Enterobacteriaceae producing extended-spectrum beta-lactamase (ESBLE) in Northern France: a five-year multicentre incidence study.

In order to measure the incidence of methicillin-resistant Staphylococcus aureus (MRSA) and of Enterobacteriaceae producing extended-spectrum beta-lactamase (ESBLE), and to evaluate the impact of the national guidelines for multidrug-resistant bacteria (MDRB) prevention in hospitals of Northern France, a multicentre study was conducted for three months every year starting in 1996, in volunteer hospital laboratories. All clinical specimens positive for MRSA and ESBLE were prospectively surveyed. During the five-year surveillance period, the overall proportion of MRSA was 38.4% in the 28,534 strains of S. aureus, and that of ESBLE was 11.4% in the 6121 strains of Klebsiella pneumoniae and 47.7% in the 2353 strains of Enterobacter aerogenes. The overall incidence rates of clinical specimens positive for MRSA, ESBL-K. pneumoniae and E. aerogenes were 0.84. 0.05 and 0.12/1000 hospital-days (HD), respectively. In the 23 hospitals that participated in the survey every year, the proportion and incidence of ESBLE decreased. Hence, despite recommendations as for isolation precautions, MRSA remains poorly controlled and requires more effective measures.

Anti-Bacterial Agents↗

Catalytic and structural properties of IRT-21 beta-lactamase (TEM-77) from a co-amoxiclav-resistant Proteus mirabilis isolate.

Proteus mirabilis strain MAG1, a clinical isolate that is resistant to broad-spectrum penicillins and co-amoxiclav, produces inhibitor-resistant TEM (IRT)-21, a novel mutant of TEM beta-lactamase. This enzyme has a pI of 5.2 and is derived from the bla(TEM-1a) gene ancestor. It contains two major amino acid substitutions specific for co-amoxiclav resistance (Leu-69 for Met and Ser-244 for Arg) that have never been found together previously. The dramatic loss of sensitivity to clavulanic acid, the enhancement of K(m) for all beta-lactams and markedly for ticarcillin, and the decrease in the catalytic efficiency makes IRT-21 comparable to the other IRTs with substitutions at position 244 or double substitutions.

Amoxicillin-Potassium Clavulanate Combination↗

[Risk of deep infection in first-intention total hip replacement. Evaluation concerning a continuous series of 790 cases].

OBJECTIVE: Deep infections of the operative site is a rare but serious complication of first intention total hip arthroplasties. French data on infections are sparse. We studied the incidence, characteristics and potential risk factors for these infections in a consecutive series of 790 total hip arthroplasties performed as first intention implantations in a University Hospital in France. PATIENTS AND METHODS: All patients undergoing first intention total hip arthroplasty surgery between November 1995 and May 1999 were included in this study. Demographic, clinical, therapeutic and surgical data were collected. Deep infection was defined as proven presence of microorganisms in at least two preoperative samples during revision surgery. Patients were followed for 1 month to 4 years. Potential risk factors were identified with univariate analysis. Chi square and exact Fisher test were used. RESULTS: The overall incidence of deep infections was 1.11 per 100 implantations (95% CI 0.84-2.70). Delay to development ranged from 14 days to 32 months. Eleven infections were proven within the first year and 3 after one year. Two risk factors were identified: absence of systemic antibiotic prophylaxis (RR = 4.74, p = 0.03) and drainage discharge after 48 hours (RR = 3.62, p = 0.02). Other variables associated with infection with a relative risk greater than 2 were obesity, corticosteroid therapy, development of a hematoma, or difficult postoperative wound healing. CONCLUSION: The incidence observed in this series is slightly higher than generally reported in the world literature. It would be important to write an antibiotic prophylaxis protocol with prescription of systemic antibiotics for all operated patients in order to reduce this incidence. Other measures that could improve the quality of care should also be taken: re-evaluation of preoperative skin preparation protocols, systematic screening of patients carrying Staphylococcus aureus before implantation and proper care for these patients.

Adult↗

Evaluation of the contribution of isolation precautions in prevention and control of multi-resistant bacteria in a teaching hospital.

From February 1999 to January 2000, a control programme to prevent the spread multi-resistant bacteria (MRB) was implemented in a French teaching hospital. This programme focused on methicillin-resistant Staphylococcus aureus (MRSA) and Enterobacteriaceae producing extended-spectrum beta-lactamases (ESBL), and was based on the application of barrier precautions (washing hands with antiseptic soaps, wearing disposable gloves and gowns, identifying MRB carriers). No changes in antibiotic policy occurred during the year. Our aim was to conduct an evaluation of this programme by measuring incidence rates. Concurrently, the effect of barrier precautions was estimated in an indirect way, by documenting the availability of barrier precautions in MRB carriers' rooms and by analysing the monthly correlation between the supply of such material and the theoretical cumulated length of MRB carriers' isolation in six randomized wards. All MRB isolated in hospitalized patients were recorded, and differentiated between acquisition in our hospital or from elsewhere. For the analysis of trends, the year was divided in three periods of four months. Over the year, the global MRB incidence was 1.26 per 1000 patient-days (PD) [95% confidence interval (95%CI)=1.16-1.36]. The MRSA incidence was 0.89 per 1000 PD (95%CI=0.81- 0.97) and the ESBL incidence was 0.38 per 1000 PD (95% CI=0.33-0.43). The MRB incidence decreased significantly in all types of specialties except for surgical wards. The incidence decreased by 17.9% for MRSA, 54.9% for ESBL and 34.8% for both MRB. Concurrently, the proportion of strains acquired in our hospital decreased for MRSA (P for trend > or = 0.05) and ESBL (P for trend > or = 0.01), whereas the incidence of imported strains increased slightly. The proportion of multiresistant strains in S. aureus (36.8%) and Enterobacter aerogenes (37.0%) remained similar throughout the year. Thus, the decrease of the incidence concerned both resistant and susceptible strains. The availability of antiseptic soaps increased significantly (P for trend > or = 0.01). The amount of antiseptic soap ordered and the theoretical lengths of isolation were correlated on a monthly basis (Spearman coefficient = 0.72; P > or = 0.02). These results shows the efficacy of such a programme of MRB containment in a large hospital, provided barrier nursing is instigated, together with the availability of such material as antiseptic soap, to allow implementation.

Bacterial Infections↗

Coexistence of SHV-4- and TEM-24-producing Enterobacter aerogenes strains before a large outbreak of TEM-24-producing strains in a French hospital.

In 1996, a monitoring program was initiated at the teaching hospital of Amiens, France, and carried out for 3 years. All extended-spectrum beta-lactamase (ESBL)-producing Enterobacter aerogenes isolates recovered from clinical specimens were collected for investigation of their epidemiological relatedness by pulsed-field gel electrophoresis and enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) and determination of the type of ESBL harbored by isoelectric focusing and DNA sequencing. Molecular typing revealed the endemic coexistence, during the first 2 years, of two clones expressing, respectively, SHV-4 and TEM-24 ESBLs, while an outbreak of the TEM-24-producing strain raged in the hospital during the third year, causing the infection or colonization of 165 patients. Furthermore, this strain was identified as the prevalent clone responsible for outbreaks in many French hospitals since 1996. This study shows that TEM-24-producing E. aerogenes is an epidemic clone that is well established in the hospital's ecology and able to spread throughout wards. The management of the outbreak at the teaching hospital of Amiens, which included the reinforcement of infection control measures, failed to obtain complete eradication of the clone, which has become an endemic pathogen.

Bacterial Proteins↗

Detection of Chlamydia trachomatis in semen and urethral specimens from male members of infertile couples in Tunisia.

The sequelae to infection with Chlamydia trachomatis in women are an established cause of tubal infertility. However, little is known about chlamydial infection and male infertility. The main objective of this study was to evaluate the presence of asymptomatic C. trachomatis infections in urethral and semen specimens from the male members of infertile couples by means of four different methods: the direct fluorescence antibodies assay, cell culture, the Roche Cobas Amplicor polymerase chain reaction, and the presence of chlamydial local IgA antibodies by the recombinant antibody-enzyme-linked immunosorbent assay. One or more chlamydial infection markers were detected in 42 (45.7%) of the 92 examined urethral and semen specimens from the male partners of infertile couples. C. trachomatis was detected in 23.9% (22/92) of urethral specimens and in 35.9% (33/92) of semen specimens. Although there was a significant correlation between the detection of one or more chlamydial infection markers in urethral and semen specimens (p = 0.01), no significant correlation was found between the detection of C. trachomatis DNA in these samples. Furthermore, no significant association was found between the presence of chlamydial local IgA antibodies and the detection of C. trachomatis. The discrepancies in positive results found between some techniques for the detection of C. trachomatis in urethral and semen specimens might be explained by variations in the sensitivities and specificities of the tests carried out and the use of specimens from different anatomical locations. Our findings suggest that C. trachomatis seems to be widespread among the male partners of infertile couples in Tunisia. The detection of C. trachomatis in urethral or semen specimens can serve as a marker for the presence of this organism in the genital tract, which is not necessarily the cause of male infertility. The study of the correlation between the detection of chlamydial infection markers and the parameters of male fertility seems to be necessary in order to determine the direct link between chlamydial infection and male infertility and to choose the most efficient technique and most suitable specimen with which to diagnose C. trachomatis-associated male infertility.

Adult↗