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M E Reverdy

Publications and source records attributed to M E Reverdy.

At least 19 recordsLinked to original sources
PubMed2002

[Rhône-Alpes observatory of Streptococcus pneumoniae in 1999: 35 cases of meningitis].

In 1999, in Rhône-Alpes region, in a survey of resistance to antibiotics of Streptococcus pneumoniae, 35 cases of meningitis were observed. A retrospectic questionnary was sent to each participant. MICs to Penicillin, Amoxicillin and Cefotaxime were determined with ATB-PNEUMO gallery or E-test and by disk diffusion for the other antibiotics. The results were interpreted according to the recommendations of the CA-SFM. Mean age was 38.1 years (range : 1 month -78 years) and sex-ratio 2/5. Eight patients had previously received antibiotics, 22 patients had risk factors and 23 were transferred in intensive care unit. The patients received C3G + glycopeptide in 15 of 16 children and in 13/19 adults according to the consensus recommendations. Diagnostic was made on the direct examination of CSF in 83%, and blood cultures was positive in 74.3% of cases. The percentage of PRP was 48.6% with 17.1% of intermediate-amoxicilline and 14.3% intermediate-cefotaxime strains. Resistance to trimethoprim-sulfamethoxazole was 45.7%, to chloramphenicol 30% and to fosfomycin 6.9%. All the strains were susceptible to rifampicin and vancomycin. Among the 17 PRP strains, 7 were belonging to serotype 6 (6 in children). The clinical outcome was fatal in 7 male cases (20%), without risk factors in 3 children and 6 of 7 strains were susceptible to penicillin. Six patients (17%) had auditive and/or neurologic sequellaes. This study shows that nearly 50% of strains isolated in meningitis, in Rhône-Alpes region, were not susceptible to penicillin, and confirms the frequency of sequellaes while the mortality is not related with the resistance of strains to the antibiotics.

Adolescent↗
PubMed2001

Multicenter evaluation of an automated system using selected bacteria that harbor challenging and clinically relevant mechanisms of resistance to antibiotics.

A multicenter study was carried out to evaluate the performance of a new commercial automated system in comparison with that of the reference agar dilution method. Ten clinical microbiology laboratories tested a collection of 61 strains of gram-negative bacilli (49 Enterobacteriaceae and 12 Pseudomonas aeruginosa), and 6 other laboratories tested a collection of 55 strains of gram-positive cocci (10 enterococci and 45 staphylococci) against 10-20 antimicrobial agents. The strains were selected on the basis that they harbored challenging and characterized mechanisms of resistance. In comparison with the agar reference method, the automated system gave an overall essential agreement (+/-1 dilution) of 94.5%, 93.5%, and 97% for the gram-negative bacilli, enterococci, and staphylococci, respectively. According to the interpretive standards of the National Committee for Clinical Laboratory Standards, the category agreement ranged from 96 to 96.4% for the three sets of organisms. The accuracy of the automated system, as determined by the kappa test, ranged from 0.80 to 0.88, reflecting an almost perfect agreement with the reference technique. Very major, major, and minor errors obtained with the automated system were 0.3%, 2.9%, and 6.6% for gram-negative bacilli, 3.4%, 0%, and 5% for enterococci, and 1%, 1.6%, and 2.7% for staphylococci, respectively. The high rate of very major errors in enterococci was mostly due to a single strain of multidrug-resistant Enterococcus faecium, which was found susceptible to several antibiotics in a majority of participant laboratories. The use of a heavy inoculum and of a broth test medium by the automated system might account for a better expression of certain resistance mechanisms, including beta-lactamases, as compared to the agar dilution reference method. The interlaboratory reproducibility was acceptable, as shown by the narrow dispersion of MICs and by the results of quality control.

Anti-Bacterial Agents↗
PubMed2001

[Epidemic of Staphylococcus aureus nosocomial infections resistant to methicillin in a maternity ward].

Methicillin-resistant Staphylococcus aureus (MRSA) nosocomial infections frequently occur in the hospital environment, but their incidence is less often observed in neonates. In the present investigation, seventeen cases were recorded over a nine-week period (two cases per week). Pulsed field gradient gel electrophoresis confirmed the clonal character of the strain. The hypothesis of manually-transmitted infection due to contamination from multiple sources was reinforced by the fact the epidemic persisted in spite of the elimination of the main human infectious source and an absence of risk factors determined by the case-control study. The role of environmental factors in the persistence of this outbreak of MRSA infection has been considered.

Adult↗
PubMed2001

[Evaluation of the E-test and the ATB-PNEUMo battery for determining the beta-lactam MIC for Streptococcus pneumoniae in daily practice].

In 1999, during the survey of resistance of Streptococcus pneumoniae to antibiotics by 31 clinical laboratories of Rhône-Alpes area, MIC to penicillin (P), amoxicillin (AMX) and cefotaxime (CTX) of 877 PRP strains or with a diameter of inhibition to oxacillin inferior to 26 mm, were determined by each institution by E-test (n = 220 strains) or ATB-PNEUMO (n = 657 strains). MICs of these three antibiotics were determined by dilution in agar medium by the coordinating center. The essential agreement was respectively for ATB-PNEUMO and E-test 89% versus 84% for P (p > 0.05), of 86% vs 79% for AMX (p < 0.01), and of 91% vs 86% for CTX (p = 0.03). When the strains were classified in clinical category, the differences were significant (p < 0.001) for AMX (85% vs 71%) and for CTX (82% vs 75%) but not for P (73% vs 78%). ATB-PNEUMO method was more sensitive than E-test for the detection of strains susceptible to P (90 vs 73%), to AMX (83 vs 78%) and to CTX (80 vs 72%) and for the strains intermediate to AMX (90 vs 78%). On the contrary, E-test is more specific than ATB-PNEUMO for the detection of P-resistant strains (94 vs 86%). Finally, the specificity of both methods is the same for detection of P-S, AMX-R and CTX-I strains.

Amoxicillin↗
PubMed2001

Incidence of Staphylococcus aureus with reduced susceptibility to glycopeptides in two French hospitals.

OBJECTIVES: To determine the incidence of Staphylococcus aureus isolates with reduced susceptibility to glycopeptides among all clinical isolates collected consecutively in two French hospitals between November 1998 and April 1999. METHODS: Methicillin-resistant and -susceptible S. aureus isolates were screened on vancomycin- or teicoplanin-supplemented agar plates. Glycopeptide MICs were determined by the E test procedure with a high inoculum and by an agar dilution technique. Glycopeptide-intermediate S. aureus isolates were identified as homogeneously or heterogeneously resistant to vancomycin by performing population analysis. RESULTS: Of the 640 isolates recovered from 518 patients, three from the same patient and two from two different patients showed homogeneous or heterogeneous intermediate resistance to vancomycin. CONCLUSION: The incidence of glycopeptide-intermediate S. aureus (homogeneously or heterogeneously resistant) in a non-selected patient population, i.e. regardless of predisposing factors and glycopeptide therapeutics, remains low in the two French hospitals involved in the study, representing 0.6% of isolates.

Anti-Bacterial Agents↗
PubMed2001

Clinical isolate of vancomycin-heterointermediate Staphylococcus aureus susceptible to methicillin and in vitro selection of a vancomycin-resistant derivative.

A Staphylococcus aureus strain with low-level heteroresistance to vancomycin (designated MER) but susceptible to methicillin was isolated from an outpatient with conjunctivitis who did not receive any glycopeptide antibiotics. Incubation of the parent strain, MER, with increasing concentrations of vancomycin led to rapid selection of a stable progeny homogeneously resistant to vancomycin. Electron micrographs of strain MER showed enhanced cell wall thickness and abnormal septations typically seen with methicillin-resistant S. aureus having intermediate susceptibility to vancomycin.

Adult↗
PubMed2001

Performance of the chromogenic medium CHROMagar Staph Aureus and the Staphychrom coagulase test in the detection and identification of Staphylococcus aureus in clinical specimens.

CHROMagar Staph aureus (CSAM) (CHROMagar Microbiology, Paris, France) is a new chromogenic medium designed to enable detection of colonies of Staphylococcus aureus by their pink color. A total of 775 specimens were cultured in parallel on CHROMagar Staph aureus and conventional media. Among the 267 S. aureus strains recovered on at least one medium, 263 were isolated on CSAM medium (sensitivity, 98.5%), and 245 (sensitivity, 91.8%) were isolated on conventional media. The specificity of presumptive identification of S. aureus on the basis of pink colony color on CSAM medium was 97% (493 of 508). This specificity increased to 100% when coagulase detection with the Staphychrom coagulase test was added and to 98.8% when S. aureus surface components were detected by agglutination in the Pastorex Staph Plus test. Susceptibility testing of 67 S. aureus strains, performed in parallel on pink CSAM colonies and on colonies grown on blood agar, gave similar results. Thus, rapid and accurate recognition and identification of S. aureus isolates were achieved with CSAM as the primary isolation medium, followed by the staphylocoagulase Staphychrom test. Antimicrobial susceptibility testing (disk-diffusion method or ATB STAPH System) can be performed directly on pink CSAM colonies.

Chromogenic Compounds↗
PubMed2000

[Indicators of quality for hospital antisepsis].

In any health care institution, the most important quality indicator for antisepsis is the existence of systems of reference of use, secondly the knowledge of those systems and then the compliance by the different classes of professionals. These refrentials must be regularly evaluated and updated according to general consensus.

Antisepsis↗
PubMed1999

Distribution of genes encoding resistance to macrolides, lincosamides, and streptogramins among staphylococci.

The relative frequency of 10 determinants of resistance to macrolides, lincosamides, and streptogramins was investigated by PCR in a series of 294 macrolide-, lincosamide-, and/or streptogramin-resistant clinical isolates of Staphylococcus aureus and coagulase-negative staphylococci isolated in 1995 from 32 French hospitals. Resistance was mainly due to the presence of ermA or ermC genes, which were detected in 259 strains (88%), in particular those resistant to methicillin (78% of the strains). Macrolide resistance due to msrA was more prevalent in coagulase-negative staphylococci (14.6%) than in S. aureus (2.1%). Genes related to linA/linA' and conferring resistance to lincomycin were detected in one strain of S. aureus and seven strains of coagulase-negative staphylococci. Resistance to pristinamycin and quinupristin-dalfopristin was phenotypically detected in 10 strains of S. aureus and in three strains of coagulase-negative staphylococci; it was always associated with resistance to type A streptogramins encoded by vat or vatB genes and occurred in association with erm genes. The vga gene conferring decreased susceptibility to type A streptogramins was present alone in three strains of coagulase-negative staphylococci and in combination with erm genes in 10 strains of coagulase-negative staphylococci. A combination of vga-vgb-vat and ermA genes was found in a single strain of S. epidermidis.

Anti-Bacterial Agents↗
PubMed1999

[Pneumococcus observatory data in the Rhône-Alps region. Results from 1996].

Throughout 1996, 22 hospital-based laboratories in the Rhône-Alpes region of France collected pneumococcal strains and used a standardized protocol to record the following data; patient age and sex; type of specimen; and determination of susceptibility to at least the following antibiotics: oxacillin 1 microgram and 5 micrograms, erythromycin (Ery), tetracycline (Tet), chloramphenicol (Chl), rifampin (Rmp), and loracarbef. For penicillin-nonsusceptible strains (PNSSs), which were identified based on results with oxacillin, MICs for penicillin G, amoxicillin (Amx), and cefotaxime (Ctx) were determined using the E Test, at the study site and agar dilution at the coordinating center. Of the 1153 strains, 65.5% were from adults and 31.8% from children; patient age was unknown in 2.7% of cases. PNSPs (MIC > 0.06 mg/l) contributed 32.9% of strains (I: 23.3%; R: 9.6%) and were more common in children (41.1%) than in adults (28.1%). The frequency of PNSSs varied across specimen types: 27.9% in blood cultures (305 strains), 15.6% in cerebrospinal fluid (32), 38.7% in protected bronchopulmonary specimens (31), 31.5% in unprotected bronchopulmonary specimens (434), 50.8% in acute otitis media (118), and 34.4% in other specimens (221). Among PNSSs, nonsusceptibility (I + R) to other antibiotics was variable: Ery, 62.1%; Tet, 41.5%; Chl, 40.4%; Rmp, 1.1%. Corresponding figures for the overall strain population were Ery, 33.3%; Tet, 22.7%; Chl, 22.8%; Rmp, 0.9%. In addition, 56.5% of PNSSs exhibited multiple drug resistance. Resistance to amoxicillin (MIC > 2 mg/l) was demonstrated for only 5 strains. No strains were resistant to loracarbef or cefotaxime. Serotypes of the 379 PNSSs were as follows: 23F, 26.6%; 14 (25.6%); 9V (18.2%), 6 (8.7%), 15 (5%), 19 (4.5%).

Adult↗
PubMed1998

[Comparison of the results of the Etest and the method for determining minimum inhibitory concentrations in solid media for penicillin G, amoxicillin, and cefotaxime for S. pneumoniae. A multicenter study].

In 1996-1997 a multicentre study was carried out on 450 Streptococcus pneumoniae strains to compare the MICs and susceptibility categories obtained with the Etest (AB Biodisk) used under routine conditions in 22 hospital laboratories in the Rhône-Alpes region, France, with those obtained by the reference technique of agar dilution performed in a single coordinating centre. Each laboratory detected penicillin resistant pneumococci (PRP) by the oxacillin disk method (1 microgram and 5 micrograms) and determined the MICs of penicillin G (PG), amoxycillin (AMX) and cefotaxime (CTX) by the Etest. All the PRP strains were collected in the coordinating centre where MICs were carried out. The strains were classified as susceptible (S), intermediate (I) and resistant (R) according to the CASFM criteria (Comité de l'Antibiogramme de la Société Française de Microbiologie). The concordance results based on susceptibility categories are as follows: PG = 67.6%, AMX = 63.6%, CTX = 71.5%. Minor errors are as follows: PG = 31.2%, AMX = 36%, CTX = 28.5%. Major and very major errors are rare (0% to 0.6%). Agreement within 1 log2 dilution was obtained for about 80% of the strains. The minor errors results from strains clustering near the breakpoints 1 mg/l (PG) and 0.5 mg/l (AMX, CTX), and from practical difficulties in routine use of the Etest. These discrepancies may result in severe therapeutic problems. This study confirms the limits of the Etest. The authors insist on standardization and rigorous use of the Etest under routine conditions.

Amoxicillin↗
PubMed1997

[Actinomyces meyeri disseminated actinomycosis disclosing pulmonary carcinoma].

The diagnosis of severe actinomycosis parallel to that of neoplasia leads to speculation of a possible fortuitous association. Because underlying conditions such as immuno-suppression are suspected in such disease, and to strengthen this hypothesis, we report one more case of disseminated actinomycosis associated with a malignant disease, namely an epidermoid pulmonary carcinoma. The diagnosis was made by thoracotomy a few months after the infectious episode. Two years later the patient recovered. The analysis of the literature data is in favor of a fortuitous association between both diagnoses.

Actinomycosis↗
PubMed1997

[Bactericidal activity determination of Biseptine, combination of chlorhexidine, benzalkonium chloride and benzylic alcohol, on 124 hospital bacterial strains].

Biseptine is an antiseptic composed of chlorhexidine digluconate (CHX), benzalkonium chloride (BC) and benzylic alcohol. Minimal Bactericidal Concentrations (MBCs) of Biseptine were determined on 124 clinical strains: 76 Enterobacteriaceae, 16 other Gram negative bacilli, (Pseudomonas spp, Aeromonas spp, Haemophilus spp) and 32 Gram positive bacteria (Staphylococcus spp, Streptococcus spp, Listeria spp, Bacillus cereus), using microdilution method, in comparison with Hibitane Champ. Modal MBC of Biseptine was 25 mg/l of CHX/2.5 mg/l BC (1/100 dilution). Proteus (MBC: 133 mg/l CHX/ 13 mg/l CB) and B. cepacia (MBC: 100 mg/l CHX/ 10 mg/l CB) were the most resistant strains, as expected with cationic antiseptics. 4/5 Bacillus cereus, strains were weakly susceptible to Biseptine and Hibitane Champ. In Biseptine, the association of CHX and CB showed a synergic activity, MBCs are usually 2 fold lower that Hibitane Champ MBCs.

Anti-Infective Agents, Local↗
PubMed1997

Kinetics of chlorhexidine on intact skin following a single application.

Residual chlorhexidine concentrations were measured after application of a single dose on the skin of 22 healthy volunteers. Dosage by high-pressure liquid chromatography in the skin cleansers revealed that the residual concentrations were higher than chlorhexidine MICs for most organisms of the resident skin flora and some responsible for hand-borne infections, even 24 h after application.

Anti-Infective Agents, Local↗
PubMed1996

Phenotypic and genotypic (pulsed-field gel electrophoresis) characteristics of enterotoxin-A-producing Staphylococcus aureus strains.

The phenotypic (antibiotype, serotype, phagetype) and genotypic (SmaI restriction patterns using pulsed-field gel electrophoresis) characters of 162 Staphylococcus aureus epidemiologically unrelated strains were studied. Eighty-two of the isolates produced enterotoxin-A (SEA+), while 80 produced none (SEA-). None of the phenotypic characters observed were characteristic of SEA+ strains. On the other hand, the electrophoretic profiles revealed a non-random distribution of the SEA+ strains (p < 0.01 in groups PI and PIII, and p < 0.03 in group PII). It can therefore reasonably be assumed that the enterotoxin-A-producing strains did not constitute a single clone, but rather, seemed to belong to strains derived from at least three clones with distinct genetic organization.

DNA, Bacterial↗
PubMed1996

[In vitro antibacterial activity of a new fluoroquinolone, sparfloxacin, against nosocomial bacteria, and concordance curve].

Minimal inhibitory concentrations (MICs) of sparfloxacin (SFX) were determined by agar dilution for 3,164 bacterial strains isolated in 10 university hospitals; in addition, antibiograms by agar diffusion were performed with 5 micrograms disks. Activity of SFX against nalidixic acid (NAL) susceptible (S) Enterobacteriaceae was close to that of other fluoroquinolones (FQ) (MIC 50 and 90: 0.06-0.5 microgram/ml); like for other FQ, this activity was reduced against NAL intermediate and resistant (R) Enterobacteriaceae (2-16). MICs of SFX against P. aeruginosa were between 0.12 and 16 (1-32). SFX had also a good activity against NAL-S A. baumannii (CMI < or = 0.25) but this activity is reduced against NAL-R Acinetobacter (16). SFX was highly active against Haemophilus (0.016-0.06) gonococci (0.008), meningococci (0.008) and B. catarrhalis (0.008-0.03). SFX showed activity superior to the currently available FQ against methicillin susceptible staphylococci (0.06); the resistant strains [8] are usually methicillin resistant. SFX is more effective against enterococci (0.5), streptococci (0.25-0.5) and particularly pneumococci (0.25-0.5) including penicillin-resistant strains. The coefficient correlation of the regression curve is 0.876; for MIC breakpoints of 1 and 2 micrograms/ml, zone diameter breakpoints should be 20 and 16 mm.

Anti-Infective Agents↗
PubMed1996

[Kinetics of in vitro bactericidal activity of the antiseptic biseptine combining 3 active principles].

Biseptine, is an association of chlorhexidine digluconate, benzalkonium chloride and benzylic alcohol. Little is known, in literature, on this antiseptic, used for cutaneous antisepsis. We studied killing kinetic of Biseptine, at different concentrations, on 4 AFNOR bacterial strains. Killing curves were studied at antiseptic concentration of 90 to 0.1% in 10 ml of distilled water. Bacterial counts were determined after neutralization in liquid medium. Synergy of chlorhexidine and benzalkonium chloride in Biseptine, allowed to obtain similar bactericidal activity than Hibitane champ with chlorhexidine concentrations 2 fold less. At 90, 50, 25, 10 and 5% concentrations, bactericidal activity (5 log10 reduction of the initial bacterial count) was effective in one minute. After 5 to 15 minutes, activity persisted at 1 and 0.5% concentrations. The 0.1% solution was inefficacious. This report disclosed an important security margin in antiseptic activity.

Anti-Infective Agents, Local↗