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C Dupeyron

Publications and source records attributed to C Dupeyron.

36 records · Page 2Linked to original sources
PubMed1995

Methicillin-resistant Staphylococcus aureus subtyping: interest of combined antibiotyping and esterase electrophoretic typing.

Ninety-four methicillin-resistant Staphylococcus aureus isolates (MRSA) were characterized by means of two typing methods, antibiotyping and esterase electrophoretic typing. Antibiotyping, recorded on the basis of susceptibility testing of 13 antimicrobial agents, allowed the description of 18 antibiotypes, four of which comprised 30, 14, 14 and 12 strains respectively. Esterase electrophoretic typing, based on esterase activity against seven synthetic substrates after polyacrylamide-agarose gel electrophoresis, led to the description of 12 electrophoretic types, two of which were predominant with 60 and 20 strains respectively. The combined use of both typing methods yielded 32 combinations, three of which were predominant with 21, 12 and 11 strains respectively. A good differentiation of strains was achieved, particularly when the antibiotype was correlated to the electrophoretic type. Thus, the combination of antibiotyping with esterase electrophoretic typing may be proposed as a well-suited method for the characterization of MRSA strains.

Bacterial Typing Techniques↗
PubMed1995

[Outbreak of infections of Klebsiella pneumoniae with extended spectrum beta-lactamase in a hospital unit with a long and medium stay].

Fourteen extended-spectrum beta-lactamase (ES beta la) Klebsiella pneumoniae strains were isolated from 14 inpatients between February 1993 and February 1994, in a medium- and long-stay neurological unit. For this reason an epidemiological study was begun, based on strain typing and examination of patient files. Strain typing was carried out by two methods (i) the analysis of antibiotic resistance, showing 7 different antibiotypes among the 14 strains studied, (ii) the analysis of esterase and dehydrogenase electrophoretic polymorphism in polyacrylamide-agarose gel. The method was checked by analysing 11 Klebsiella pneumoniae strains with wild phenotype for beta-lactam antibiotics, which were isolated during the same period in the same unit. Simultaneously 6 other strains isolated during the same period in some other units of the hospital were analysed. Nine electrophoretic types were found among the 31 strains (wild and ES beta las). The analysis of the results showed that 8 isolates of the group of 14 ES beta las had the same antibiotype and electrophoretic type. This demonstrates that one epidemic strain was responsible for two outbreaks, the first one in April and the second one in August-September. A case control investigation was carried out to define the risk factors of infection. Files were examined for the 14 infected inpatients and for 20 control inpatients from the same unit during the same period. Statistical analysis was performed with Epi Info software 5 (CDC Atlanta). Length of stay, dependence and malnutrition levels, and urinary sphincter disfunction were the most significant risk factors.

Anti-Bacterial Agents↗
PubMed1994

Rapid emergence of quinolone resistance in cirrhotic patients treated with norfloxacin to prevent spontaneous bacterial peritonitis.

We carried out quantitative culturing of stools from 31 hospitalized alcoholic patients with cirrhosis and ascites, before treatment with 400 mg of norfloxacin per day, weekly for the first month, and then every 2 weeks thereafter for 15 to 229 days (median, 54 days). Members of the family Enterobacteriaceae virtually disappeared from the stools (< 10(2)/g), but treatment had little effect on enterococci. No selection of resistant organisms occurred in 15 patients, but the remaining 16 patients developed fecal organisms resistant to fluoroquinolones between days 14 and 43 of treatment (median, 25 days). Staphylococcus aureus was isolated four times, coagulase-negative Staphylococcus spp. were isolated six times, Citrobacter freundii was isolated four times, Enterobacter cloacae was isolated three times, Klebsiella oxytoca was isolated twice, Proteus rettgeri was isolated once, and untypeable streptococci were isolated six times. Some isolates persisted, while others were transient (one to seven consecutively positive cultures). The MICs of four quinolones (nalidixic acid, norfloxacin, ofloxacin, and ciprofloxacin) were determined by use of experimental microwell strips (ATB CMI; Biomerieux S.A.). All the strains isolated before treatment were susceptible to the four quinolones, with low MICs, whereas those isolated during norfloxacin treatment were highly resistant. Long-term norfloxacin administration thus carries a risk of disturbing the bacterial ecology in these patients, suggesting that digestive decontamination should no longer be prescribed routinely to cirrhotic patients with ascites.

Ascites↗
PubMed1981

[Effect of Gram-negative bacteria on fatty acids].

The gram-negative bacteria investigated exert various effects on fatty acids. P. aeruginosa and A. calcoaceticus catabolize any of the fatty acids tested. S. marcescens is effective upon all fatty acids excepting butyric acid. The long chain fatty acids only are degraded by E. coli, meanwhile the other fatty acids present a bacteriostatic or bactericidal activity on it. The authors propose a simple and original method for testing the capability of degradation of fatty acids by some bacterial species.

Bacteria↗
PubMed1981

[Comparison of three methods of measuring antibiotic sensitivities (author's transl)].

Two semi-automatic methods of measuring antibiotic sensitivities were compared to the disk method for everyday use in a bacteriology laboratory. The reproducibility, compared with 3 strains, proved satisfactory, the highest was the API method. There appeared to be few discrepancies between the semi-automatic methods and the disk method. Part of the latter may be explained by the difference of critical concentrations. Others, routine for a few antibiotics, merit more complete study.

Anti-Bacterial Agents↗