[Bactericidal activity determination of Biseptine, combination of chlorhexidine, benzalkonium chloride and benzylic alcohol, on 124 hospital bacterial strains]. / Détermination de l'activité bactéricide de la Biseptine, associant chlorhexidine, chlorure de benzalkonium et alcool benzylique, sur 124 souches bactériennes hospitali eres.

Biseptine is an antiseptic composed of chlorhexidine digluconate (CHX), benzalkonium chloride (BC) and benzylic alcohol. Minimal Bactericidal Concentrations (MBCs) of Biseptine were determined on 124 clinical strains: 76 Enterobacteriaceae, 16 other Gram negative bacilli, (Pseudomonas spp, Aeromonas spp, Haemophilus spp) and 32 Gram positive bacteria (Staphylococcus spp, Streptococcus spp, Listeria spp, Bacillus cereus), using microdilution method, in comparison with Hibitane Champ. Modal MBC of Biseptine was 25 mg/l of CHX/2.5 mg/l BC (1/100 dilution). Proteus (MBC: 133 mg/l CHX/ 13 mg/l CB) and B. cepacia (MBC: 100 mg/l CHX/ 10 mg/l CB) were the most resistant strains, as expected with cationic antiseptics. 4/5 Bacillus cereus, strains were weakly susceptible to Biseptine and Hibitane Champ. In Biseptine, the association of CHX and CB showed a synergic activity, MBCs are usually 2 fold lower that Hibitane Champ MBCs.

[Determination of bactericidal minimum concentrations of 3 antiseptics and 1 disinfectant on 580 hospital gram-negative bacilli]. / Détermination de la concentration minimale bactéricide de trois antiseptiques et un désinfectant sur 580 souches de bacilles gram négatifs d'origine hospitalière.

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.

Susceptibilities to antibiotics and antiseptics of new species of the family Enterobacteriaceae.

One hundred and sixty-nine strains of new species of the family Enterobacteriaceae, isolated mainly from the environment, were tested to determine their susceptibilities to 13 antibiotics and 4 antiseptics or disinfectants. All the species were susceptible to aminoglycosides, doxycycline, and trimethoprim but were resistant to chloramphenicol. Susceptibility to beta-lactams varied more among the strains. However, all the strains were cefotaxime susceptible, apart from some Buttiauxella agrestis strains for which MICs were greater than 256 micrograms/ml. The antiseptic MBCs were similar to those published elsewhere for species of the Enterobacteriaceae of clinical origin. No resistance to chlorhexidine was observed. On the other hand, the environmental strains presented a greater resistance to active chlorine than did the reference strains.

[Application of a micromethod to the study of the bactericidal activity of 2 antiseptics based on chlorhexidine gluconate]. / Application d'une microméthode à l'étude de l'activité bactéricide de deux antiseptiques à base de gluconate de chlorhexidine.

Minimal bactericidal concentrations (MBCs) of two antiseptics containing chlorhexidine digluconate (5% for the A solution, 1.5% for the B solution) were determined using a microdilution method. This method is a miniaturization of the Afnor T 72150 standard for antiseptics and disinfectants. 133 hospital isolates were studied, including 68 Enterobacteriaceae, 11 Acinetobacter, 18 Pseudomonas, 1 Achromobacter, 23 Staphylococcus, and 12 S. faecalis. Each microplate was seeded with eleven of these strains and one reference strain (E. coli CIP 54127, P. aeruginosa CIP A22, S. aureus CIP 53154, and S. faecium CIP 5855). Ten microliter of a standardized inoculum (2 to 3 10(8) bacteria/ml) were added to 90 microliters of a solution containing the antiseptic. Each antiseptic was tested in various concentrations (1.95 to 125 mg/l for A and 1.17 to 75 mg/l for B). After five minutes contact at 21 degrees C, 1.5 microliter from each well was seeded on a neutralizing agar plate (letheen agar + 3% tween 80 + 0.3% lecithin + 3% saponin + 0.1% histidine). The neutralizing effectiveness of this plate on the antiseptics in the concentrations used had been ascertained previously. The Afnor T 72150 standard was established for each reference strain. MBCs 90 (in mg/l) found were as follows: 31.2 (A) and 18.8 (B) for Enterobacteriaceae, 15.6 (A) and 9.4 (B) for Acinetobacter, 31.2 (A) and 18.8 (B) for Pseudomonas, 62.5 (A) and 37.7 (B) for Staphylococcus and 125 (A) and 37.5 (B) for S. faecalis.(ABSTRACT TRUNCATED AT 250 WORDS)

[Comparative study of 3 methods for quantifying bacterial flora of the hands: membrane filtration, agar inclusion and plate culture]. / Etude comparative de trois méthodes de numération de la flore des mains: filtration sur membrane, inclusion en gélose, étalement en surface.

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.

[Verification of the effectiveness of neutralization in the in vivo study of antiseptics]. / Vérification de la validité de la neutralisation dans l'étude des antiseptiques in vivo.

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.

[Effectiveness of 9 soaps and/or antiseptics on hand flora after surgical-type washing]. / Efficacité de neuf savons et/ou antiseptiques sur la flore des mains après un lavage de type chirurgical.

We studied the effect of nine soaps and/or antiseptics on the bacterial flora of hands 5 minutes after a surgical scrub. Each agent was used by ten healthy volunteers, free of skin lesions. The following agents were used: chlorhexidine gluconate 4% and 1.5%, povidone iodine 4%, ethanol 70 degrees, isopropanol 70 degrees, a non-antiseptic soap, and another soap followed by either ethanol 70 degrees, isopropanol 70 degrees or a preparation containing H2O2. The surgical scrub procedure varied slightly according to whether or not the agent was soapy and required rinsing. Sampling was carried out using Gaschen's bag method with 400 ml of neutralising solution. Counts were made after 48 hours aerobic incubation at 35 degrees C on tryptic soy agar with 1% Tween 80, and after 8 days anaerobic incubation at 35 degrees C on Brewer's yeast agar with 1% Tween 80. Results were expressed as the log 10 to the number of bacteria per hand. Statistical significance was determined using the Student t test. The greatest reduction in aerobic flora was produced by isopropanol 70 degrees C (1.7 log 10). 1.5 to 0.5 log 10 reductions were produced, in the following decreasing order, by ethanol 70 degrees, povidone iodine, chlorhexidine gluconate 4% and 1.5% and a soap with ethanol 70 degrees. A reduction of less than 0.5 log 10 was produced by a soap with isopropanol 70 degrees, and soaps with H2O2. Similar results were obtained with the facultative anaerobes.

[Skin flora of the hands, elbow-hollow and fore-arm (author's transl)]. / Etude de la flore cutanée normale des mains, du pli du coude et de l'avant-bras.

During five years, the values of the skin flora of the hands, fore-arm and elbow-hollow were studied on volunteers, especially five of them. Samples were taken according to the washing method. Results show important quantitative variations of the flora between the differents volunteers and even for a same volunteer. In the five long term followed subjects, the differences were: 2.17 log 10 for aerobic flora and 1.97 log 10 for aeroanaerobic flora of the hands, 3.90 log 10 for aerobic flora and 3.88 log 10 for aero-anaerobic flora of the fore-arm, 2.95 log 10 for aerobic flora and 3.35 log 10 for aero-anaerobic flora of the elbow-hollow. These variations remained independent of the season. According to these variations, already notified by others authors it is suggested first to standardize sampling and bacteriological methods, second to develop multicentric programs in view to increase the number of subjects to be included in the study.

[Skin flora of the hands, elbow-hollow and fore-arm (author's transl)]. / Etude de la flore cutanée normale des mains, du pli du coude et de l'avant-bras

During five years, the values of the skin flora of the hands, fore-arm and elbow-hollow were studied on volunteers, especially five of them. Samples were taken according to the washing method. Results show important quantitative variations of the flora between the different volunteers and even for a same volunteer. In the five long term followed subjects, the differences were 2,17 log 10 for aerobic flora and 1,97 log 10 for aero-anaerobic flora of the hands, 3,90 log 10 for aerobic flora and 3,88 log 10 for aero-anaerobic flora of the fore-arm 2,95 log 10 for aerobic flora and 3,35 log 10 for aero-anaerobic flora of the elbow-hollow. These variations remained independent of the season. According to these variations, already notified by others authors it is suggested first to standardize sampling and bacteriological methods, second to develop multicentric programs in view to increase that number of subjects to be included in the study.