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M E Reverdy

Publications and source records attributed to M E Reverdy.

At least 37 records · Page 2Linked to original sources
PubMed1995

[Comparison of different phenotypic methods with polymerase chain reaction (PCR) for the detection of resistance to oxacillin in coagulase negative staphylococci].

The mecA gene which confers the oxacillin resistance has been searched by PCR in 290 (124 positives, 166 negatives) coagulase-negative staphylococci (CNS) belonging to twelve species. The results were compared with the oxacillin MIC values obtained by agar dilution (4% NaCl) or by the ATB STAPH method (Api-bioMérieux; 0%, 2%, 5% NaCl) and growth inhibitory diameters obtained by agar diffusion with an oxacillin disk placed at 30 degrees C without NaCl, or at 35 degrees C in presence of 2% or 5% NaCl. Sensitivity of oxacillin resistance detection depends upon the salt concentration and the method used. The optimum concentration is 2%. With this concentration, the Api ATB test appears as the more performant (sensitivity: 89.8%). Search for the mecA gene by PCR represents a very interesting method that detects 96.9% of the oxacillin-resistant CNS strains.

Bacteriological Techniques↗
PubMed1994

Laboratory diagnosis of oxacillin resistance in Staphylococcus aureus by a multiplex-polymerase chain reaction assay.

A polymerase chain reaction (PCR) test was developed in which the mecA gene responsible for the intrinsic resistance to oxacillin in Staphylococcus aureus and the gyrA gene, always present in this species, were amplified in one operation. Among the 468 clinical isolates tested, the results obtained for 454 of the isolates (97%) were consistent with those of MIC determination. Discrepant results were noted for strains with low-level oxacillin resistance (MICs, 4-8 micrograms/ml) and mecA gene negative. For these strains, susceptibility to oxacillin was restored in the presence of a beta-lactamase inhibitor, which suggested a resistance by penicillinase hyperproduction. In contrast, all of the high-level resistant strains (MICs, > 8 micrograms/ml) carried the mecA gene. The presence of this gene has frequently been associated with resistance to gentamicin, tetracycline, erythromycin, lincomycin, and pefloxacin. The PCR assay described in this study can be accomplished with ease and total confidence in the clinical microbiologic laboratory for a rapid and effective establishment of antistaphylococcal chemotherapy.

Bacterial Proteins↗
PubMed1994

[Relationship between the level of minimal inhibitory concentrations of five antiseptics and the presence of qacA gene in Staphylococcus aureus].

The Polymerase Chain Reaction (PCR) was used to detect the qacA gene which encodes antiseptic resistance in 186 clinical isolates of Staphylococcus aureus. The results were compared with those obtained by MIC determination of 4 antiseptics (benzalkonium chloride, hexamidine, chlorhexidine, acriflavine) and for ethidium bromide. The qacA gene was not detected among the 32 susceptible S. aureus strains, but was found in the 70 (85%) of the 82 S. aureus strains resistant to all 5 antiseptics. The gene was also detected in 70 (45%) of the 154 remaining strains that were resistant to at least one antiseptic.

Acriflavine↗
PubMed1993

Endocarditis due to Staphylococcus lugdunensis: report of 11 cases and review.

Staphylococcus lugdunensis is a recently described coagulase-negative staphylococcus that has been associated with human infections, including nine reported cases of infective endocarditis. The present study describes 11 other cases of infective endocarditis caused by this organism. The infection occurred in patients whose mean age was 61 years and was community-acquired in most cases. A preexisting cardiac abnormality was present in eight patients. Three of the 11 infections involved prosthetic valves. Ten strains were susceptible to penicillin. The destructive course of the infection, the need for valve replacement, and the high mortality suggest that S. lugdunensis causes a virulent form of endocarditis.

Adult↗
PubMed1993

[Evolution of resistance to antibiotics and antiseptics of hospital Staphylococcus aureus strains isolated from 1980 to 1991].

From 1980 to 1991, 925 non epidemic hospital isolates of S. aureus were selected and phage typed. MIC of 20 antibiotics and 4 antiseptics were determined by agar dilution method. The proportion of isolates susceptible to all antibiotics remains constant; however the trend to the resistance is strong during the study period (oxacillin 10-->20%, erythromycin 17-->28%, pefloxacin 4-->19%...). Strains resistant to oxacillin become more and more multiple resistant; some of recent isolates are resistant to 7 antibiotic families. There are very few products active against these strains i.e, glycopeptides (100%), pristinamycin (96%), fusidic acid (94%). This finding implies the need for continuous surveillance at the local and national level.

Aminoglycosides↗
PubMed1993

[Evaluation of a micromethod for the bactericidal activity of five disinfectants on 108 hospital strains].

The authors studied 5 disinfectants containing aldehyde and quaternary ammonium against 108 hospital strains. The minimal bactericidal activities (MBC) were determined with a microdilution method and the dilution-neutralization method (AFNOR T 72-150). The microdilution method results were validated using the MBCs of four reference strains tested with the dilution-neutralization method (AFNOR T 72-150). 3 disinfectants proved to be valuable. 1 disinfectant was valuable but with a MBC toward all bacteria only a dilution away from the dilution of use. 1 disinfectant was determined as unsatisfactory as 9.5 p. cent of all strains proved resistant toward it. All disinfectants matched AFNOR standards; but those specifications did not match toward hospital strains. Such an evaluation using a simple and reliable method should be of use.

Acinetobacter↗
PubMed1991

[In vitro antibacterial activity of a new oral cephalosporin, ceftibuten. Results of a multicenter study].

Minimal inhibitory concentration (MIC) of ceftibuten (CBT) were evaluated by agar dilution for 1,416 bacterial strains isolated in 5 hospitals. For Enterobacteriaceae, MIC 50 and 90% were respectively (micrograms/ml): (I) Naturally non beta-lactamase producing species: E. coli 0.12-0.5, Shigella 0.06-0.12 and Salmonella 0.03-0.12, P. mirabilis 0.16-0.03. (II) Chromosomal penicillinase producing species: K. pneumoniae 0.03-0.5 and K. oxytoca 0.03-0.06. (III) Chromosomal cephalosporin producing species: E. cloacae and C. freundii 1- greater than 128: S. marcescens 0.25-2; indole + Proteus 0.06-0.12. Activity of CBT was not modified on plasmid mediated penicillinase producing strains; however, CBT was inactive on cephalosporinase hyperproducing strains, and its activity was variably reduced on broad spectrum beta-lactamases producing strains. CBT was inactive on P. aeruginosa (MIC greater than or equal to 32) and on A. baumannii (8- greater than 128). Haemophilus and Gonococci, regardless on beta-lactamase production status, were very susceptible to CBT (MIC 50 and 90%: 0.06-0.5 and 0.016-0.06); it is the same situation for Meningococci; B. catarrhalis was generally inhibited by 0.03 to 2 (strains susceptible to penicillin G) and 0.12 to 16 (strains resistant to penicillin G). CBT was inactive on Staphylococci. Enterococci and Streptococci B were generally resistant; Streptococci A, C, G were inhibited by low concentrations: 0.06 to 1 (MIC 50 and 90%: 0.25-0.5), whereas MIC for other Streptococci 0.12 to 128 (MIC 50 and 90%: 8-128) and for Pneumococci were 0.25 to 16 (4-8). These antibacterial properties particularly against Enterobacteriaceae placed CBT in excellent position among oral cephalosporins.

Acinetobacter↗
PubMed1990

Intestinal decontamination in a polyvalent ICU. A double-blind study.

A double blind, placebo-controlled trial was performed to test the efficacy of prevention of nosocomial infections by selective digestive decontamination. Placebo or tobramycin (80 mg) and colistin (100 mg) was given four times daily via the gastric tube. Amphotericin B (500 mg/6 h) was administered to all patients. As our ICU is divided into two separate subunits, intestinal decontamination or placebo was administered alternatively to patients of the two subunits during two 3-month periods, separated by a 2-month period without prevention. The decontamination (n = 97) and placebo groups (n = 84) were similar with respect to age, sex, severity score and diagnostic categories on admission. Intestinal decontamination alone failed to significantly reduce the number of infected patients (26% vs 34.5%, p = 0.20), but was effective on ICU-acquired infections (0.33 vs 0.60, p = 0.02) especially gram-negative infection rates (0.17 vs 0.43, p = 0.01). The onset of the first ICU-acquired infection was delayed (9 vs 13 days, p less than 0.001) and incidence of pneumonia (2 vs 13 cases, p less than 0.01) including bacterial pneumonia (0 vs 8 cases, p less than 0.01) was significantly decreased. However, mean ICU stay and mortality were not significantly modified by intestinal decontamination.

Amphotericin B↗
PubMed1990

Cefazolin and netilmicin serum levels during and after cardiac surgery with cardiopulmonary bypass.

The kinetics of cefazolin and netilmicin were studied in 10 patients undergoing elective cardiac surgery with hemodilution and cardiopulmonary bypass (CPB). During surgery, but before CPB, cefazolin, 25 mg/kg, and netilmicin, 2 mg/kg, were administered intravenously over 30 minutes. For the 48-hour period following CPB, cefazolin, 25 mg/kg, and netilmicin, 1 mg/kg, were administered intravenously every 8 hours. Initiation of CPB was accompanied by a 28% to 30% decrease in hematocrit and serum antibiotic levels. At the conclusion of surgery, cefazolin and netilmicin serum levels were 41 +/- 12 micrograms/L and 2.5 +/- 0.6 micrograms/mL (mean +/- SD), respectively. During the postoperative period, cefazolin levels were consistently greater than the minimum inhibitory concentration (MIC) for sensitive bacteria (4 micrograms/mL); average netilmicin levels were greater than MIC of sensitive bacteria (2 micrograms/mL) for 2 hours after antibiotic infusion. The netilmicin trough levels were 0.6 +/- 0.5 micrograms/mL. Pharmacokinetic parameters were determined using a model-independent method, and gave the following results during surgery: cefazolin--elimination half-life, 231 minutes, total body clearance, 1.05 mL/kg/min, and steady-state volume of distribution, 243 mL/kg. The values for netilmicin were 249 minutes, 1.18 mL/kg/min, and 353 mL/kg, respectively. Postoperatively there were no significant changes in the disposition of cefazolin, but the elimination half-life of netilmicin was shorter (124 minutes, P less than 0.01) and the total body clearance greater (3.58 mL/kg/min, P less than 0.01) than during surgery.

Adolescent↗
PubMed1990

[Hospital infection in the maternity department. 3 years of surveillance in 9,204 deliveries of which 1,333 were cesarean sections].

Hospital or nosocomial infection, or infection acquired in hospitals, is a health problem in all hospital departments and particularly in the maternity department. We report on a prospective survey of surveillance of hospital-acquired infections both from the mother and the baby's point of view after delivery vaginally or with caesarean carried out at the obstetrical clinic of the Edouard Herriot Hospital in Lyon (France) over three successive years with a series of 9,204 deliveries. The incidence of infection in women who were delivered without caesarean section was 1.37% when urinary tract infections had been excluded but 13% in women who had caesarean sections. Endometritis, skin infections and urinary tract infections were the leading causes. As far as the newborn were concerned, hospital infection ran at about 2.60% and this in the main was due to staphylococcal pustules in the skin. These figures are still too high and prevention should be based on more information given and more care taken by the whole staff of such a hospital.

Cesarean Section↗
PubMed1989

Clinical isolates of Staphylococcus lugdunensis and S. schleiferi: bacteriological characteristics and susceptibility to antimicrobial agents.

The bacteriological characteristics and susceptibility to antimicrobial agents of 108 clinical isolates of Staphylococcus lugdunensis and Staphylococcus schleiferi are described. Fifty out of 108 isolates were considered to be responsible for 16 documented infections, including some severe infections (endocarditis, bacteraemia, osteitis). A number of bacteriological characteristics enabled the identification of these species in the clinical microbiology laboratory: the absence of coagulase and protein A, and the presence of a fibrinogen affinity factor and thermonuclease along with other biochemical characteristics (ornithine and arginine decarboxylases, carbohydrate acidification, novobiocin susceptibility) differentiated these new species from other staphylococci; however, they did not possess virulence markers such as toxins or haemagglutinin, but were haemolytic. In this series, almost all isolates were susceptible to 22 antibiotics and 4 antiseptics representative of the main groups of antimicrobial agents. More information is needed on the ecology and epidemiology of these new opportunistic pathogens.

Adult↗
PubMed1989

Oxacillin and tobramycin serum levels during cardiopulmonary bypass.

Antibiotic prophylaxis in cardiac surgery is recommended to combat acquired infections caused by staphylococci and gram-negative bacilli. Prophylaxis seems effective provided blood levels are greater than minimal inhibitory concentrations (MIC). In this study, two doses of antibiotics were compared in 45 patients with normal renal function during cardiopulmonary bypass (CPB). All patients received 50 mg/kg of oxacillin. Group 1 (30 patients) also received 1 mg/kg of tobramycin, while group 2 (15 patients) received 2 mg/kg of tobramycin. Blood samples were taken after the administration of antibiotics, as well as at the onset and conclusion of CPB. Additional samples were taken before and after heparin injection before CPB, and from the arterial and venous cannulae of the bubble oxygenator during CPB. In both groups, oxacillin serum levels were constantly greater than MIC for susceptible bacteria. In group 1, tobramycin levels less than 2 micrograms/mL (MIC for most susceptible bacteria) occurred in four patients before CPB, in 14 patients at the onset of CPB, and in 19 patients at the conclusion of CPB. These low levels were not explained by heparin administration or absorption onto the CPB circuit, but were the result of hemodilution. In group 2, in which all the tobramycin levels were higher than 2 micrograms/mL, serum levels decreased from 9.9 +/- 3.4 (mean +/- SD) to 3.7 +/- 0.7 micrograms/mL throughout the procedure. Plasma creatinine did not change significantly in either group. It is concluded that in patients with normal renal function, doses as high as 50 mg/kg of oxacillin and 2 mg/kg of tobramycin may be necessary before CPB to provide adequate serum levels throughout CPB.

Adult↗
PubMed1989

Standardized method for evaluation of hand disinfection by surgical scrub formulations.

A standardized protocol for the evaluation of hand disinfection by surgical scrub formulations was applied to volunteers in a multicenter trial. Povidone iodine (PVI), chlorhexidine (CHX), and a nonmedicated soap (NMS) were tested. The scrubbing procedure involved three daily hand washings for five consecutive days; surviving bacteria were counted daily after being collected in a suitable neutralizing solution. Immediate efficacy (IE), cumulative efficacy (CE), and remanent effect (RE) were calculated by reference to the control hand. Statistical analyses of IE, CE, and RE showed significant differences among the three scrub formulations. IEs of PVI and CHX were equivalent and different from IE of NMS; CE and RE of CHX were higher than those of PVI and NMS. On the basis of the statistical analysis, the population size required for further studies aimed at detecting significant differences between surgical scrub formulations could be estimated.

Adult↗
PubMed1989

[Determination of bactericidal minimum concentrations of 3 antiseptics and 1 disinfectant on 580 hospital gram-negative bacilli].

Minimal bactericidal activities (MBCs) of three antiseptics (povidone iodine, chlorhexidine digluconate, benzalkonium chloride) and one disinfectant (sodium hypochloride) where determined, on 580 hospital Gram negative bacilli. Previously the Afnor T 72-150 standard for antiseptic and disinfectant was established for two reference strains E. coli CIP 54 127 and P. aeruginosa CIP A 22. No difference was found between the MBC obtained with these strains in Afnor standard and in microdilution method. Microdilution method allows to test 11 hospital isolates and one reference strain. A strain was considered as resistant when the MBC was one dilution higher than the reference strain MBC. Results were as follows: None strain was resistant to sodium hypochloride and povidone iodine; 18.2% Enterobacteriaceae were resistant to chlorhexidine digluconate with 94.2% of Proteus; 4% of Enterobacteriaceae were resistant to benzalkonium chloride with 89.5% of Proteus and only 1.8% other bacilli. Results obtained in the present study are similar as those previously published particularly with Proteus; nevertheless other studies have reported P. aeruginosa strains resistant to chlorhexidine digluconate and benzalkonium chloride; this last point was not observed in our study.

Benzalkonium Compounds↗