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C Quentin

Publications and source records attributed to C Quentin.

At least 37 records · Page 2Linked to original sources
PubMed1997

Molecular epidemiology of an outbreak due to extended-spectrum beta-lactamase-producing enterobacteria in a French hospital.

Between June 1992 and June 1993, 128 extended-spectrum beta-lactamase-producing enterobacteria (123 Klebsiella pneumoniae, 3 Escherichia coli, 1 Enterobacter aerogenes, and 1 Citrobacter diversus) were collected in a French university hospital. These isolates were recovered mainly from patients hospitalized in intensive care and neurosurgery units. The 128 strains were divided into 14 antibiotypes (ATBs; ATB1 to ATB14); 102 of 103 nonredundant isolates were shown to produce an SHV-4-related extended-spectrum beta-lactamase (pl 7.8, hybridization with a blaSHV probe); the remaining strain (Kp 2108) produced a TEM-3-related extended-spectrum beta-lactamase (pl 6.3, hybridization with a blaTEM probe). For representative isolates, five plasmid profiles (Pl to Pll-4), eight ribotypes (E1 to E8), and seven arbitrarily primed polymerase chain reaction profiles (A1 to A7) were obtained. The results suggest the spread of an epidemic strain of Klebsiella pneumoniae (E1, A1, Pl, various ATBs) from an intensive care unit throughout the hospital. Another epidemic strain (E2, A2, pl, ATB4) was confined to the neurosurgery unit. Other extended-spectrum beta-lactamase-producing Klebsiella pneumoniae of ribotypes distinct from E1 or E2 might result from the spread of an epidemic plasmid, such as reported for isolates of other enterobacterial species. Conversely, they might represent imported cases, such as the strain Kp 2108, which produced a TEM-3-related beta-lactamase.

Cross Infection↗
PubMed1997

In vitro activity of fosfomycin combined with ceftazidime, imipenem, amikacin, and ciprofloxacin against Pseudomonas aeruginosa.

The in vitro activity of fosfomycin in combination with ceftazidime, imipenem, amikacin, or ciprofloxacin was studied by an agar plate checkerboard method against 40 clinical isolates of Pseudomonas aeruginosa with various antibiotic resistance profiles. Fosfomycin/ciprofloxacin appeared to be the most effective combination (synergy 15%, addition 80%, indifference 5%), followed by fosfomycin/amikacin (synergy 7.5%, addition 52.5%, indifference 40%), fosfomycin/imipenem (addition 37%, indifference 63%), and fosfomycin/ceftazidime (addition 20%, indifference 80%). The effects of the combinations were not significantly influenced by the antibiotic susceptibility patterns of the strains.

Amikacin↗
PubMed1997

Molecular epidemiology of a nosocomial outbreak due to SHV-4-producing strains of Citrobacter diversus.

Over a 6-month period, eight strains of Citrobacter diversus (Citrobacter koseri) resistant to extended-spectrum cephalosporins and monobactams were isolated from seven colonized and/or infected patients from the same intensive care unit. All strains harbored a single large conjugative plasmid which mediated an extended-spectrum beta-lactamase of the SHV-4 type (ceftazidimase phenotype; enzyme pI, 7.8; plasmid DNA hybridization with a blaSHV-specific probe). All strains were characterized by antibiotic resistance pattern analysis, beta-lactamase content analysis, plasmid profiling, ribotyping with EcoRI, and arbitrarily primed (AP)-PCR with primers O8 and O12. Among the eight C. diversus strains, strains Cd5 to Cd12, six isolates (isolates Cd6 to Cd11) were identical by all markers; one strain (strain Cd5) differed by two markers (antibiotype and AP-PCR pattern with primer O8), and the remaining strain (strain Cd12) differed by two other markers (ribotype and AP-PCR pattern with primer O12). Our results suggest that six of the eight SHV-4-producing C. diversus strains studied (strains Cd6 to Cd11) were a single epidemic strain. Strain Cd5 could be related to the epidemic strain; the origin of strain Cd12 remains uncertain.

Bacterial Typing Techniques↗
PubMed1997

[Comparative in vitro activity of cefepime: multicenter study in Aquitaine].

Over a 6 month-period (1st January to 30th June 1995), the results of antibiotic susceptibility testing routinely performed for beta-lactams against enterobacteria, Pseudomonas aeruginosa, and Acinetobacter in 7 laboratory hospitals of Aquitaine, have been collected and divided in susceptibility profiles. A total of 9269 strains (7323 enterobacteria, 1667 P. aeruginosa, 279 Acinetobacter) have been examined. On the whole, cefepime (91,5%) and ceftazidime (91,7%) were the most active cephalosporins, followed by cefpirome (87,9%) and cefotaxime (80,4%); imipenem was the most active beta-lactam agent (97,4%). When the strains were divided according to their susceptibility profiles, the advantage of cefepime was shown to be related to its excellent activity against enterobacteria: all strains susceptible to cefotaxime and ceftazidime (CTX/CAZ-S) were susceptible to cefepime, as were most of the strains with an intermediate susceptibility or resistant to these drugs (CTX/CAZ-I/R, approximately 5% of the enterobacteria). The latter strains exhibited a phenotype corresponding either to the overproduction of their chromosomal cephalosporinase (approximately 20% of the species belonging to group 3) or to the synthesis of an extended spectrum beta-lactamase (19% of the strains of Klebsiella pneumoniae). Cefepime was active against 93% of the derepressed mutants of enterobacteria, including 3 imipenem resistant isolates of Enterobacter. CAZ-S strains of P. aeruginosa (84%) were usually susceptible to cefepime (80%), as were 6% of the CAZ-I/R strains. CAZ-S strains of A. baumannii (16.3%) were generally susceptible to cefepime (83%), as were 3.2% of the CAZ-I/R strains.

Acinetobacter↗
PubMed1997

[Vaccines available in France as of 1 January 1997].

The vaccines available in France as of January 1, 1997 are listed. For each one, the nature of the vaccine, indications, efficacy, safety, contraindications, vaccinal calendar have been detailed.

Clinical Protocols↗
PubMed1996

Epidemiological study of an outbreak of infection with Staphylococcus aureus resistant to lincosamides and streptogramin A in a French hospital.

A significant increase in the incidence of isolates of methicillin-resistant Staphylococcus aureus (MRSA), that were also resistant to lincosamides and streptogramin A (LSA-MRSA), was observed in a French university hospital. Twenty-seven isolates from the outbreak were characterised, including 17 isolates from a plastic surgery ward and six control strains of MRSA. The strains were examined by antibiotyping and biotyping, and by three molecular methods: plasmid analysis, ribotyping and insertion sequence (IS) typing with IS256 sequence as a probe. Antibiotyping (five antibiotypes) was discriminatory because of the uncommon resistance phenotype of the epidemic strain. Biotyping (three biotypes), DNA plasmid analysis (four profiles) and ribotyping (two profiles) were poorly sensitive, in contrast to IS-typing (12 profiles). By the latter method, a coefficient of similarity (percentage similarity) compared to the predominant IS profile was calculated. Strains with a coefficient of similarity > or = to 82% were considered as highly related to the epidemic strain, while those with a coefficient of similarity < or = to 40% were regarded as distant. Results obtained with the five markers confirmed that an outbreak of hospital infection had occurred in the plastic surgery ward, with spread of the epidemic strain throughout the hospital.

Adult↗
PubMed1996

Epidemiological study of an outbreak due to multidrug-resistant Enterobacter aerogenes in a medical intensive care unit.

In 1993, 63 isolates of Enterobacter aerogenes were collected from 41 patients in a medical intensive care unit (ICU). During the same period, only 46 isolates from 32 patients were collected in the rest of the hospital. All isolates were analyzed by antibiotic resistance phenotype, and 77 representative isolates were differentiated by plasmid restriction analysis, ribotyping, and arbitrarily primed (AP)-PCR. The extended-spectrum beta-lactamases produced by 22 strains were characterized by determination of their isoelectric points and by hybridization of plasmid DNA with specific probes. The isolates were divided into 25 antibiotic resistance phenotypes, either susceptible (group I) or resistant (group II) to aminoglycosides, and exhibited three phenotypes of resistance to beta-lactams: chromosomally derepressed cephalosporinase alone or associated with either extended-spectrum beta-lactamases (mainly of the SHV-4 type) or imipenem resistance. The results of the tests divided the 77 representative isolates (group I, n = 21; group II, n = 56) into 15 plasmid profiles, 14 ribotypes, and 15 AP-PCR patterns. Although the resistant isolates (group II) exhibited different plasmid profiles, ribotyping and AP-PCR analysis demonstrated an identical chromosomal pattern, indicating an epidemiological relatedness. They were mainly found in the medical ICU and occasionally in other units. The susceptible strains (group I) had various and distinct markers and were mainly isolated in units other than the medical ICU. In conclusion, the presence of a nosocomial outbreak in an ICU and the spread of a multidrug-resistant epidemic strain throughout the hospital was confirmed. Ribotyping and AP-PCR represent discriminatory tools for the investigation of nosocomial outbreaks caused by E. aerogenes.

Disease Outbreaks↗
PubMed1994

[Susceptibility of strict anaerobic bacteria to antibiotics in France: a multicenter study].

During 1992, the in vitro antibiotic susceptibility of 462 anaerobic bacteria was performed in 7 hospitals, by the reference agar dilution method. Among the 222 Bacteroides fragilis group strains, only one Bacteroides fragilis strain was resistant to imipenem and all bêtalactams, even combined with bêtalactamase-inhibitors while metronidazole resistance could not be detected. One major outer membrane protein (probably a porin) was lacking in some of the six amoxicillin-clavulanic acid resistant Bacteroides fragilis group strains. Evolution in antibiotic resistance rates could be assessed only for clindamycin and piperacillin whose resistance rates increased to 14 and 15.8 p. cent, respectively. On the whole anaerobic strains resistance rates were: imipenem 0.2, ticarcillin-clavulanic acid 0.5, amoxicillin-clavulanic acid or metronidazole 1.5, piperacillin 9.1, cefotaxime-sulbactam 9.7, cefoxitin 12.8, clindamycin 13.7, cefotaxime 27.2, amoxicillin 45 and ciprofloxacin 70, respectively.

Anti-Bacterial Agents↗
PubMed1991

In vitro studies of elastin-fibrin biomaterial degradation: preservative effects of protease inhibitors and antibiotics.

The degradability of a new elastin-fibrin material was tested in vitro versus human pancreatic elastase (HPE) and plasmin (PL) activities. It is shown that aprotinine Iniprol, a well-known protease inhibitor and Eglin C, a new potent inhibitor of HPE, especially when used in synergy, efficiently protected the material. A small amount of specific antibiotics was incorporated into the material. The two products will allow the material to be used in digestive surgery with improved safety.

Adsorption↗
PubMed1991

Susceptibility of Bacteroides ureolyticus to antimicrobial agents and identification of a tetracycline resistance determinant related to tetM.

The in-vitro activity of ten antimicrobial agents was evaluated for 28 clinical isolates of Bacteroides ureolyticus, an obligate anaerobe associated with non-gonococcal urethritis. The isolates were characterized by plasmid DNA profile and PAGE protein pattern. All isolates were inhibited at concentrations equal to or lower than the recommended breakpoint concentration for ampicillin (16 mg/l), metronidazole (16 mg/l) and erythromycin (4 mg/l). Twenty-seven isolates were inhibited by less than or equal to 2 mg/l of ciprofloxacin, pefloxacin and ofloxacin. Four isolates were tetracycline-resistant requiring 2-64 mg/l of tetracycline, minocycline or doxycycline for inhibition. In two tetracycline-resistant isolates tetM was demonstrated by dot-blot and Southern hybridizations. These two isolates did not contain a plasmid and had a PAGE protein pattern type III. These data confirm the spread of the tetM determinant in various bacteria of the genital tract.

Anti-Bacterial Agents↗
PubMed1991

Evaluation of AN-Ident.

AN-Ident (Analytab Products, Inc., Plainview, N.Y.) is a ready-to-use system for anaerobe identification. It is based on the detection of constitutive preformed enzymes, is growth independent, and requires only 4 h of aerobic incubation. This micromethod was evaluated for its ability to identify anaerobic bacteria by using a conventional methodology as a reference. Of 265 clinical isolates, AN-Ident accurately identified 241 (91%) of the isolates to the species level and 259 (98%) of the isolates to the genus level, with limited supplemental testing needed (5%). The AN-Ident system performed well for the most common pathogens but less satisfactorily for infrequently isolated and/or asaccharolytic species; expansion and updating of the data base would be helpful. Although some color reactions were difficult to interpret, the commercial kit was easy to use.

Bacteria, Anaerobic↗
PubMed1989

Clostridium difficile and its cytotoxin in diarrhoeic stools of hospitalized patients. Toxigenic potential of the isolates.

Cytotoxin assay and culture for Clostridium difficile were performed on 303 diarrhoeic stools from 261 hospitalized patients. Specimens from 42 patients were positive by at least one of the methods, and 40 of them had an antibiotic-associated diarrhoea. The cytotoxin assay was positive in 5 of 7 patients with pseudomembranous colitis. Thirteen had an appropriate response to specific therapy and the remainder have resolved of diarrhoea without C. difficile directed chemotherapy. These findings show the lack of reliability of the cytotoxin assay for the diagnosis of C. difficile antibiotic-associated diarrhoea. The 6 strains isolated from patients with pseudomembranous colitis were examined for enterotoxin by the rabbit ileal loop test: 4 produced both toxins, 2 only enterotoxin. Both toxins could therefore not be essential for the clinical expression of the disease.

Anti-Bacterial Agents↗
PubMed1988

Comparative in vitro activity of cefpiramide, a new parenteral cephalosporin.

The in vitro activity of cefpiramide was compared with that of nine other cephalosporins by determining the MIC values by means of an agar dilution method for 300 representative clinical isolates of nonfastidious bacteria. Cefpiramide had a broad-spectrum of activity, similar to that of the third-generation cephalosporins. As judged by the MIC50 and the MIC90 values, cefpiramide was one of the most active cephalosporins against Pseudomonas aeruginosa (MIC50 2.9 micrograms/ml, MIC90 64 micrograms/ml), staphylococci (MIC50 1.2 micrograms/ml, MIC90 10 micrograms/ml) and Enterococcus faecalis (MIC50 13 micrograms/ml, MIC90 43 micrograms/ml). Cefpiramide had moderate activity against Enterobacteriaceae (MIC50 4 micrograms/ml, MIC90 108 micrograms/ml), comparable to that of the older second-generation cephalosporins. Ticarcillin-resistant strains of gram-negative rods were inhibited by higher concentrations of cefpiramide than ticarcillin-susceptible strains.

Bacteria↗