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Y Brun

Publications and source records attributed to Y Brun.

At least 37 records · Page 2Linked to original sources
PubMed1989

Hospital dispersion of Staphylococcus epidermidis isolates resistant to a fluoroquinolone, pefloxacin.

Since 1985, nosocomial infections have been frequently treated with a new fluoroquinolone, pefloxacin, at the Cardiological and Neurological Hospital in Lyon. From 1986 to 1988, the incidence of resistance of clinical Staphylococcus epidermidis strains to pefloxacin increased from 31 to 57%. Dispersion of these resistant strains in the hospital environment was recognized when they were detected on 22% of staff members' fingers (139 samples were investigated) and in 28% of the environmental samples (180 were investigated). There was an association between carriage rate and work place. Most of the pefloxacin-resistant S. epidermidis were resistant to oxacillin, gentamicin, erythromycin, cotrimoxazole and fosfomycin. Intensive use of pefloxacin selected multiresistant S. epidermidis which became ubiquitous in the hospital environment.

Carrier State↗
PubMed1989

Susceptibilities to ceftriaxone of streptococcal strains associated with infective endocarditis.

We determined the bactericidal activity of ceftriaxone on 20 streptococci isolated from patients with infective endocarditis and that of penicillin G on 5 strains. The MICs of ceftriaxone were less than or equal to 2 micrograms/ml and the MBCs were low for 5 nontolerant strains (less than or equal to 2 micrograms/ml) and high for 15 tolerant strains (greater than or equal to 16 micrograms/ml). The maximal reduction of the viable bacterial counts after 24 h of exposure to antibiotic was achieved for a concentration of ceftriaxone of 4, 32 and 256 micrograms/ml, respectively for 5, 10 and 19 strains. The activity of penicillin G was similar.

Ceftriaxone↗
PubMed1988

[Sensitivity of Pseudomonas aeruginosa and Klebsiella spp. to ceftazidime. Current status in France].

Ceftazidime was tested against 2,224 strains of Pseudomonas aeruginosa obtained from 17 hospitals in April, May and June, 1986 and against 607 strains of Klebsiella pneumoniae and 234 strains of K. oxytoca obtained from 16 hospitals in October, 1987. The MIC's of ceftazidime against P. aeruginosa were distributed normally, with an MIC50 of 2 mg/l and an MIC90 of 4 mg/l. Depending on critical concentrations, 80 per cent of strains were sensitive, 11.4 per cent were of intermediate sensitivity and 0.54 per cent were resistant. There were few differences in results between hospitals. Ninety-two per cent of resistant strains and 45 per cent of intermediate strains (as opposed to 6 per cent of all strains) produced a high-level constitutive cephalosporinase with little variations between centres. The MIC's of ceftazidime against K. pneumoniae and K. oxytoca had a bimodal distribution: 91 per cent of strains were sensitive to 0.25 mg/l, 6 per cent of strains showed intermediate sensitivity and 3 per cent were resistant. All intermediate and resistant strains produced a very broad spectrum beta-lactamase which hydrolyzed some of the third generation cephalosporins: K. pneumoniae 36 CTX-1, 5 SHV-2, and 14 strains producing a recently identified beta-lactamase "CAZ-5/SHV-4"; K. oxytoca 3 CTX-1. These strains were isolated in 10 of the 16 hospitals which took part in the 1987 study. Comparison of these results with those of studies performed in 1984 and 1985 showed a moderate increase in the number of intermediate sensitivity strains of P. aeruginosa and the occasional occurrence, of the epidemic type, in some hospitals of Klebsiella spp. producing very broad spectrum beta-lactamases which were rare in 1985.

Ceftazidime↗
PubMed1988

Characterization of clinically significant isolates of Staphylococcus epidermidis from patients with endocarditis.

Biotyping, slime production, bacteriophage typing, serotyping, antibiograms, and plasmid profiles were used to characterize 19 Staphylococcus epidermidis strains isolated from 12 patients with prosthetic valve endocarditis and from 7 patients with native valve endocarditis. With the API Staph battery, 12 different biocodes with, at the most, three differences were obtained. Slime production was found for 10 strains (53%). Agglutinogens investigated by agglutination with two specific sera were found for 12 strains (63.1%). Three strains were phage typable (15.2%). Against a panel of nine antimicrobial agents, 15 different profiles were found. Multiply antibiotic-resistant strains were isolated from patients with prosthetic valve endocarditis when disease onset occurred less than 18 months after heart surgery and from patients with native valve endocarditis who received antibiotics immediately prior to their illness. All of the strains were available for plasmid analysis, and all the DNA profiles were distinct. On gels run in Tris-borate buffer, 73.7% of the strains had large plasmids of more than 30 megadaltons. A small plasmid of 2.8 megadaltons was found in multiply resistant strains and in strains resistant only to tetracyclines. None of the isolates appeared to be the same strain, and the bacteriological differences between the strains were confirmed mainly by the antibiotic susceptibility profile and the plasmid pattern analysis. These bacteriological results were in agreement with the clinical data.

Bacteriophage Typing↗
PubMed1988

Restriction endonuclease analysis of Staphylococcus epidermidis DNA may be a useful epidemiological marker.

We compared the epidemiological markers of 13 Staphylococcus epidermidis strains isolated from an adult inpatient during a febrile episode and 23 S. epidermidis strains isolated during a presumptive outbreak of nosocomial infection in a neonatal ward. The total DNA restriction endonuclease analysis (REA) was processed along with the following conventional markers: biotyping, serotyping, phage typing, antibiotic susceptibility profiles, and plasmid profiles. The REA method was reproducible, giving stable results both in vitro and in vivo. For the hospitalized adult patient, the conventional markers of the 13 strains were concordant and the restriction profiles were identical. Five restriction groups were demonstrated during the course of the outbreak. Within two of the groups, the identities of all of the markers were used to verify whether all of the isolates belonged to the same cell clone. In a third group, combined analysis of the conventional markers and REA had to be used to demonstrate isolate similarity. On the other hand, in another group, none of the markers were similar; interpretation was not easy. An epidemiological study of S. epidermidis infections in hospitals must take into account all of the epidemiological markers: biotypes, serotypes, phage types, antibiograms, plasmid profiles, and REA.

Bacterial Typing Techniques↗
PubMed1988

Susceptibilities of streptococcal strains associated with infective endocarditis to nine antibiotics.

The susceptibilities of 121 streptococcal strains isolated from patients with infective endocarditis to mezlocillin, piperacillin, ceftizoxime, ceftriaxone, ceftazidime, imipenem, ciprofloxacin, ofloxacin and pefloxacin were determined by the agar dilution technique. Viridans streptococci, Streptococcus bovis and Enterococcus faecalis were susceptible to imipenem, mezlocillin and piperacillin. All the strains, except E. faecalis were sensitive to ceftriaxone, ceftizoxime and ceftazidime and resistant to ciprofloxacin, ofloxacin and pefloxacin. E. faecalis strains were moderately resistant to the new quinolons.

Anti-Bacterial Agents↗
PubMed1988

[In vitro activity of roxithromycin compared to 5 other macrolides against staphylococci].

This study aimed to compare the bacteriostatic activity of roxithromycin (RU) to those of erythromycin (ERY), troleandomycin (TAO), spiramycin (SPI), josamycin (JOS) and midekamycin (MID) against staphylococci strains. 239 strains of hospital origin were analysed: S. aureus (139), coagulase negative staphylococci (CNS) (100). The MIC were determined by the agar dilution method. The modal MIC, the MIC 50 and 90 observed for the both groups of strains are given according to species and antibiotics. This study gives the opportunity to classify the 6 antibiotics in a decreasing order considering their antistaphylococcal activity: RU = ERY, TAO = SPI, JOS = MID. No difference was noticeable between S. aureus and CNS strains.

Anti-Bacterial Agents↗
PubMed1985

Studies on staphylococci from toxic shock syndrome in France, 1981-1983.

Staphylococci from 22 cases of toxic shock syndrome with onsets between 1981 and March 1983 have been studied. Another four cases were detected by abstract surveillance. Three of these patients died. The case histories show that the syndrome occurs in women during menstruation as well as in males and in children, and is associated with Staphylococcus aureus infections. The production of enterotoxins (A, B, C) and toxic shock toxin by S. aureus isolates from toxic shock syndrome was investigated. Twenty-two of the 23 isolates were found to be toxigenic: 7 produced enterotoxin A, 8 produced enterotoxin B, 3 produced enterotoxin C and 13 produced toxic shock toxin. The latter was found with enterotoxin A in five cases, and with enterotoxins A and B in only one case. Sixty-three percent of 46 S. aureus strains isolated from the vagina of patients with diseases other than toxic shock syndrome produced toxin; eight of these strains produced toxic shock toxin.

Adolescent↗
PubMed1985

[Influence of technical factors in the determination of minimal inhibitory concentration by microdilution].

Minimal inhibitory concentrations (MICs) of a new quinolone, norfloxacin, as determined by agar dilution are greater than those found using a liquid dilution micromethod. We report herein an analysis of the various parameters possibly involved in this discrepancy: Mueller-Hinton and BioMérieux, glass or plastic, small or large inoculum, and comparative volumes in which the inoculum (IN) and antibiotic (AB) are presented (1 ml IN + 1 ml AB or 1.5 microliter IN + 50 microliter AB or 50 microliter IN + 50 microliter AB). Volume of the inoculum suspension had a bearing on the results obtained with all three reference strains tested. Norfloxacin MICs for S. aureus 7625 and P. aeruginosa 76110 increased commensurately with the ratio of inoculum volume to antibiotic volume, and vice versa. In contrast, no significant variation was found for E. coli 7624. To evaluate the frequency of this effect, we tested 40 antibiotics on the reference strains, and several antibiotics on savage strains (16 Enterobacteriaceae, 40 Staphylococcus, 12 Pseudomonas and 17 P. aeruginosa). The significance of inoculum and antibiotic volumes was corroborated for some antibiotics. Results most consistent with the reference method were obtained with 50 microliter inoculum and 50 microliter antibiotic solution.

Agar↗
PubMed1985

[Comparative clinical trial of cefoperazone versus ampicillin + tobramycin in severe bronchopulmonary and pleural infectious pathology].

This study involved an open trial with parallel randomised series receiving either cefoperazone (2 g/d) or a combination of ampicillin (6 g/d) and tobramycin (3 to 4 mg/kg/d). The 30 patients included were of both sexes (male predominance), hospitalised, aged 62 +/- 11,5 years and suffering from a severe bronchopulmonary or pleural infection. Underlying pathology was serious (neoplasm, C.O.D.L., bronchiectasis, cardiac pathology). No significant difference was seen in the sampling of the two populations. Cefoperazone was prescribed in 2 infusions per 24 hours. Ampicillin was given as 3 infusions, followed by tobramycin administered by a similar number of injections. The duration of treatment was 16.8 +/- 9 days (cefoperazone) and 11,8 +/- 6,5 days (ampicillin + tobramycin). Overall evaluation (clinical, radiological and laboratory criteria) showed 88% (cefoperazone group) and 71% (ampicillin + tobramycin group) recovery and improvement rates. There were two failures in the cefoperazone group and 6 failures in the other group. These results were not statistically different. Three of the 6 failures could be attributed to resistance of the initial bacteria or selected by one or other type of treatment. None of the antibiotics prescribed raised any acceptability problems.

Aged↗
PubMed1984

[In vitro activity of ceftizoxime on hospital bacteria. Results of a multicenter study].

The susceptibility to ceftizoxime of all bacterial strains isolated from seven university-affiliated hospitals over one month was tested with disk-diffusion technique. Additionally, the MIC of 1937 strains selected at random was evaluated by the agar dilution method. The majority of Enterobacteriaceae are inhibited at a concentration of less than 1 microgram/ml with a mode MIC varying from 0.008 to 0.12 among the various groups. A few Enterobacter and Citrobacter strains are resistant. Little activity was demonstrated by ceftizoxime on Pseudomonas aeruginosa and Acinetobacter sp. (mode MIC 32 and 8 micrograms/ml respectively). Haemophilus sp. (MIC 0.01-0.03) and Neisseria (MIC less than 0,008-0,016) are very susceptible to the drug. The MIC of methicillin-sensitive strains of Staphylococcus aureus varies from 1 to 4 micrograms/ml ; Enterococci are less susceptible, whereas other Streptococci and Pneumococci have low MICs (less than 0.008-0.025). The susceptibility of anaerobic pathogens varies widely between species, and within species ; MIC ranges from 0.008 to 32 micrograms/ml for Clostridium sp. and 0.25 to 128 micrograms/ml for Bacteroides sp.

Bacteria↗
PubMed1984

[Comparative multicenter study of 2 methods of determining sensitivity to antibiotics. Gel diffusion method and semiautomatic method in fluid ABAC medium].

Susceptibility of 60 bacterial isolates to 15 antibiotics was determined by two methods in three laboratories: 48 Gram negative bacilli and 12 Staphylococci were selected because of "intermediate" susceptibility to at least one antibiotic. Results show a good correlation between the two methods: more than 90% for carbenicillin, cefazolin, cefoxitin, cefamandole, kanamycin, tobramycin, amikacin, erythromycin, pristinamycin and fusidic acid, between 80 and 90% for penicillin G, ampicillin, oxacillin, gentamicin, doxycycline, chloramphenicol, spiramycin and clindamycin, less than 80% for neomycin, tetracycline, minocycline and oleandomycin. Interpretation criteria are different in the two methods for rifampicin, colistin and cotrimoxazole. Between the three laboratories, correlation was 90,3% and 88,6% for disc diffusion method and ABAC system respectively.

Anti-Bacterial Agents↗
PubMed1984

[Antibiotic susceptibility testing by the disk method. Comparative evaluation of 5 commercial systems].

The systems studied were: bioMerieux, Difco, Institut Pasteur Production, Oxoid (media, discs, standards of interpretation). Each batch was tested for pH value and calcium and magnesium concentrations. The activity of 19 antibiotics was determined by use of three reference strains (E. coli ATCC 25922, S. aureus ATCC 25923, P. aeruginosa ATCC 27853). The most suitable inoculum was defined after testing three different methods of preparation. The susceptibility of each strain to each antibiotic was studied 30 times using each system. The reproducibility of the diameters with each system and the intersystem variance was calculated. This allowed groups of homogeneity between the different systems to be defined. The results were interpreted according to the various existing standards (manufacturer, French committee of SFM, WHO) yielding an overall discordance of 0,29%, of little practical importance. Finally the reliability of each system was evaluated according to WHO, data. The Difco medium gave the most accurate results with the other media tending to produce excessively large zones of inhibition.

Anti-Bacterial Agents↗
PubMed1984

[Evaluation of the use of rifampin combinations in severe staphylococcal infections. Apropos of the selection of 7 resistant mutants].

Selection of rifampicin-resistant Staphylococcus aureus has been described in vitro and in vivo when this compound is given as monotherapy or orally. That this occurrence may be prevented by combination antibiotic therapy is generally accepted. We report 25 cases of severe staphylococcal infection treated by a synergistic association of rifampicin with an aminoglycoside, vancomycin, or a macrolide. Therapy failed as a result of selection of the same rifampicin-resistant Staphylococcus aureus (serotype and lysotype) in seven cases. This finding may be explained by insufficient diffusion or inactivation of the other antibiotic in the infection site.

Adolescent↗
PubMed1984

[Multicenter study of the antibacterial activity of a new cephalosporin: CM 40874].

Minimal inhibitory concentrations (MIC) of CM were evaluated on 2 548 bacterial strains isolated in 8 hospitals. CM demonstrated high activity on Enterobacteriaceae, the MIC being less than or equal to 0.125 micrograms/ml for 71% of the 1 362 strains tested, less than or equal to 1 for 99.6%, and less than or equal to 4 for 99.9%. Mode MIC varies little among the different groups of Enterobacteriaceae (from 0.06 to 0.12 micrograms/ml), with the exception of Serratia sp. (mode MIC : 0.25) and Klebsiella oxytoca (mode MIC : 0.03). Most of Enterobacter, Serratia, and Citrobacter sp. strains not inhibited by cefotaxime are readily inhibited by CM at the same concentrations than susceptible strains. CM has less activity on P. aeruginosa (MIC 2-32 micrograms/ml) and Acinetobacter sp. (MIC 8-128). Staphylococci (MIC 32) and Enterococci are not susceptible. Variable activity is found against other Streptococci. CM inhibits Haemophilus sp. at MICs of 0.12 to 0.5 micrograms/ml and Gonococci at MICs of 0.03 to 0.5 (whether the strains produce beta-lactamase or not). Meningococci have a mode MIC of 0.03 micrograms/ml (range 0.008 to 0.25). Thus, CM 40874 is a new third generation cephalosporin with high activity on Enterobacteriaceae, including those strains not susceptible to cefotaxime and good activity on Haemophilus sp. and Neisseria sp. This additional activity is probably supported by enhanced resistance to enzymatic inactivation by beta-lactamases.

Bacteria↗