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J Fleurette

Publications and source records attributed to J Fleurette.

At least 145 records · Page 8Linked to original sources
PubMed1985

Determination of the activity on Legionella of eight macrolides and related agents by comparative testing on three media.

It has proved difficult to develop a standard method for the determination of minimum inhibitory concentrations (MICs) of antibiotics against the Legionellaceae. A major obstacle has been the inactivation of certain antibiotics by components of Charcoal Yeast Extract agar, especially charcoal. To determine the MICs of eight macrolides and related agents (erythromycin, spiramycin, oleandomycin, josamycin, midecamycin, lincomycin, clindamycin and pristinamycin) for 36 strains of Legionella, we used two charcoal-free media: Buffered Yeast Extract agar and Buffered Antibiotic Medium no. 1 (BAM1), the latter having been developed in our own laboratory. The inhibitory effect of charcoal was most marked on josamycin and pristinamycin. This effect was absent on the charcoal-free media, which both, however, inhibited spiramycin. BAM1 agar seemed the better of the two charcoal-free media as it gave more consistent growth. The most active agents were josamycin (0.06-0.25 mg/l), pristinamycin (0.06-0.5 mg/l) and erythromycin (0.12-0.5 mg/l). Midecamycin (0.12-1 mg/l) and spiramycin (1-5 mg/l) also had useful activity.

Anti-Bacterial Agents↗
PubMed1985

Septicemia caused by Agrobacterium sp.

Agrobacterium radiobacter biovar 2 was repeatedly grown from the blood of an elderly patient receiving artificial ventilation and broad-spectrum antibiotics. No source of the organism was found, but the septicemia ceased when cefotaxime was given. Sera from the patient showed a fourfold rise in antibody against the organism and higher titers than sera from all but 1 of 50 healthy blood donors. The organism did not contain the plasmid associated with plant oncogenicity. This case may be only the second in which Agrobacterium sp. has been clearly linked with human infection.

Aged↗
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↗
PubMed1984

Differentiation of Enterobacteriaceae and Vibrionaceae by a micromethod for determination of carbon substrate assimilation.

The assimilation techniques described for taxonomic study are unsuitable for routine diagnosis because of the need for purification and standardization of substrates, the great quantity of medium consumed and difficulties in interpreting the results. A standardized micromethod (API strip) for the study of carbon substrate assimilation by bacteria has recently been described (Zbl. Bakt. Hyg., I. Abt. Orig. A 255 (1983) 479-488). The prototype gallery used consisted of two strips of 32 microtubes each containing dehydrated carbon substrate. Each strip contained 30 tests plus positive and negative controls. The suspension medium was a synthetic semi-gel. A total of 914 strains of Gram negative rods representing 44 species of Enterobacteriaceae and Vibrionaceae were tested (Table 1). Automatic reading was performed after incubation at 32 degrees C for one day, or two days for slow growing bacteria using an ATB - 1500 reader (API System) linked to a HP 85 microcomputer (Hewlett-Packard). Most species showed typical carbon substrate assimilation patterns allowing their differentiation from other species within each genus (Table 2). The results obtained with the micromethod agreed in large measure with the nutritional patterns reported by other workers. It should be possible to use these results to construct a coherent framework of tests suitable for identifying species of Enterobacteriaceae and Vibrionaceae of clinical significance.

Bacteriological Techniques↗
PubMed1984

Differentiation of gram negative rods other than Enterobacteriaceae and Vibrionaceae by a micromethod for determination of carbon substrate assimilation.

The assimilation techniques described for taxonomic study are unsuitable for routine diagnosis because of the need for purification and standardization of substrates, the great quantity of medium consumed and difficulties in interpreting the results. A standardized micromethod (API Strip) for the study of carbon substrate assimilation by bacteria has recently been described (Zbl. Bakt. Hyg., I. Abt. Orig. A 255 (1983) 479-488). The prototype gallery used consisted of two strips of 32 microtubes each containing dehydrated carbon substrate. Each strip contained 30 tests plus positive and negative controls. The suspension medium was a synthetic semi-gel. A total of 1046 strains of Gram-negative rods representing 41 species belonging to the genera Pseudomonas, Alcaligenes, Moraxella, Acinetobacter, Flavobacterium and to the EF4 group were tested (Tables 1 to 6). Automatic reading was performed after incubation at 32 degrees C for one day, or two days for slow growing bacteria, using an ATB 1500 reader (API System) linked to a HP 85 microcomputer (Hewlett-Packard). Most species showed typical carbon substrate assimilation patterns allowing their differentiation from other species within each genus. The results obtained with the micromethod agreed in large measure with the nutritional patterns reported by other workers. It should be possible to use these results to construct a set of tests suitable for identifying species of Gram-negative rods other than Enterobacteriaceae and Vibrionaceae.

Acinetobacter↗
PubMed1984

Indices of effectiveness of medical and surgical treatment in 40 cases of prosthetic valve endocarditis.

Forty patients with prosthetic valve endocarditis (PVE) presenting during a 12-year period at a single hospital were studied. Twenty-six were male and 14 female and ages ranged from 19 to 67 years. During the first six post-operative months, most episodes were caused by staphylococci (38%) and Gram negative bacilli (24%). Between 6 and 11 months no episodes were seen, but thereafter streptococci predominated (50%). The overall mortality was 58% (66% during first six months; 36% thereafter). Nine of 23 patients undergoing re-operation died, most deaths occurring in patients in cardiac failure prior to surgery. Eleven deaths occurred in the 17 patients treated with antibiotics alone. Six of these were pyrexial at death and all but one was infected by a virulent organism. The remaining five were apyrexial at death and all had staphylococcal PVE. Our findings suggest: (1) all cases occurring during the first six months should be initially treated as 'early' PVE; (2) in staphylococcal PVE, apyrexia may not mean cure; (3) the principal guides to prognosis in PVE are the patient's cardiac status and the nature of the infecting organism.

Adult↗
PubMed1984

Evaluation of the API 20 STREP system for species identification of streptococci associated with infective endocarditis.

A rapid commercial system (API 20 STREP gallery, API System, France) for the identification of streptococci was compared with conventional biochemical or serological methods. 77 clinical isolates from patients with infective endocarditis and six reference strains were tested. Biochemical tests showing differences between conventional methods and the API gallery were the acidification of inulin and the Voges-Proskauer reaction, but these differences did not affect the final identification of any strain. 75 strains were identified by the API system and 70 by conventional methods. 69 strains (25 groupable and 44 of 51 non-groupable streptococci) were given the same identity by both methods. One S. morbillorum was only identified by the conventional method. Seven S. sanguis I strains were identified only by the API system and confirmed by additional biochemical tests. The API gallery is a useful method for identifying streptococci associated with infective endocarditis, agreeing with conventional methods in 90% of strains. Results are usually available in 24 h.

Bacteriological Techniques↗
PubMed1984

Antibiotic susceptibility of streptococcal strains associated with infective endocarditis.

Seventy-six strains of various species of streptococci isolated from patients with infective endocarditis were tested for their susceptibility to 13 antibiotics by an agar dilution method. The antibiotics tested were: benzyl-penicillin, ampicillin, cefotaxime, vancomycin, erythromycin, rifampicin, pristinamycin, gentamicin, netilmicin, tobramycin, amikacin, dibekacin and streptomycin. Excluding enterococci, 91% of strains were sensitive to benzylpenicillin. Resistance to benzylpenicillin was only found in some strains of S. sanguis I, S. sanguis II and S. mitis. Enterococci were more sensitive to ampicillin. Cefotaxime was highly active against all strains, except enterococci. Vancomycin was active against all strains. Resistance to erythromycin was found in 16% of isolates. Rifampicin and pristinamycin were highly active against all strains, except some enterococci. Gentamicin and netilmicin were the most active of the six aminoglycosides tested. High level resistance to streptomycin was seen in six strains. Overall, S. agalactiae was more resistant to the aminoglycosides than the other species. Among the non-groupable streptococci, strains of S. mitis, S. sanguis I and S. sanguis II were the least sensitive to many antibiotics. Benzylpenicillin remains the antibiotic of choice for the treatment of IE caused by streptococci. If the MIC exceeds 0.1 mg l-1, an aminoglycoside (netilmicin or gentamicin) should be added and the duration of treatment increased from 4 to 6 weeks.

Aminoglycosides↗
PubMed1984

Nosocomial colonization and infection by Achromobacter xylosoxidans.

Achromobacter xylosoxidans, a bacterial species named in 1971, is often isolated from aqueous environments, but little has been reported about its pathogenicity in humans, its epidemiological pattern, and its susceptibility to antibiotics and antiseptics. We were faced with an epidemic caused by this microorganism for 18 months in an intensive care unit. Two patients had fatal infections and 37 others were colonized. The source was the deionized water of the hemodialysis system. The 46 isolates were identified by comparison with the reference strain A. xylosoxidans ATCC 27061. The characteristic cellular fatty acids of this species were demonstrated by gas-liquid chromatography. The minimal inhibitory concentrations of 27 antibiotics were determined. The isolates were susceptible to only two: moxalactam at 4 micrograms/ml and ceftazidime at 8 micrograms/ml. The minimal bactericidal concentrations of one disinfectant and three antiseptics were: sodium hypochloride, 109 micrograms/ml; chlorhexidine digluconate in ethanol solution, 15 to 125 micrograms/ml; polyvinylpyrrolidone iodine, 750 micrograms/ml; and iodine ethanol, 312 to 625 micrograms/ml.

Alcaligenes↗
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 study of 3 methods for quantifying bacterial flora of the hands: membrane filtration, agar inclusion and plate culture].

We report a study comparing three methods of quantifying bacterial flora on hands: filtration on a 0.22 mu membrane, pour-plate method, and conventional plate culture. Forty samples were taken using Gaschen's bag method with 400 ml of buffer solution. The bacteria in each sample were then counted using each method in duplicate. By adjusting the size of the sample and the number of dilutions, a countable number of colonies was obtained with each method. Culture media, and incubation time and atmosphere were the same for all three methods. Results, expressed as the log 10 of the number of bacteria per hand for aerobic and facultative anaerobic organisms respectively were as follows: membrane filtration 5.65 +/- 0.72 and 6.02 +/- 0.62; pour-plate 5.81 +/- 0.68 and 5.83 +/- 0.62; surface culture 5.80 +/- 0.69 and 5.97 +/- 0.52. None of the differences were statistically significant. The three methods were then compared for manipulation time, cost, volume of sample required and ease of reading and subsequent speciation. Overall, the pour-plate method emerged as the best, especially if speciation is required.

Agar↗
PubMed1984

[Verification of the effectiveness of neutralization in the in vivo study of antiseptics].

Well defined controls of the effectiveness of antiseptic neutralizing agents in vitro already exist (Afnor Standards for antiseptics and disinfectants). Conversely, there is currently no standard method for verifying how effectively such agents neutralize antiseptics which have been applied to the skin. We describe a method in which the neutralizing solution is first applied to the antiseptic-treated skin and then filtered to remove skin flora. The effect of the neutralizing agent is then checked using a test organism (Staphylococcus epidermidis ATCC 14990) in parallel with four controls: viability of the test organism (T1), activity of the untreated antiseptic (T2), non-bactericidal effect of the neutralizing agent (T3) and of skin secretions (4). Skin sampling was carried out using Gaschen's bag method for the hands and the Williamson and Kligman method modified by Fleurette for other sites. Twelve soaps and/or antiseptics were studied. In each case, activity of the antiseptic (T2) was confirmed, except when the product under study was a non-bactericidal soap. Bacterial counts obtained in controls T3 and T4 and in the neutralization test itself were always greater than 80% of the control value (T1). Occasionally, the counts in the neutralization test exceeded 100% of the T1 value, probably because of the dispersal effect of the triton X100 present in the neutralizing solution. This method thus offers a means of standardizing the study of antiseptics in vivo. In addition, the test organism, Staphylococcus epidermidis, is more representative of the skin flora than the bacterial strains recommended by Afnor for in vitro studies.

Anti-Infective Agents, Local↗
PubMed1984

[Comparison of 2 systems for identifying nonfermenting or fermenting oxidase-positive gram-negative bacilli].

The N/F FLOW and API 20 NE identification systems were compared for their ability to identify 182 strains of either non-fermentative or fermentative oxidase-positive gram-negative bacilli. Agreement with the identification given by conventional methods was achieved for 91,7 per cent of strains by the API System but for only 81,9 per cent of strains by the N/F System. Complementary tests were needed to identify 35,4 per cent of strains using the API System but 65,2 per cent using the N/F System.

Bacteriological Techniques↗
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↗