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A C Vautrin

Publications and source records attributed to A C Vautrin.

10 recordsLinked to original sources
PubMed2005

Efficiency of blood culture bottles for the fungal sterility testing of corneal organ culture media.

BACKGROUND/AIM: The consequences of fungal contamination of an organ cultured cornea, though exceptional, are often disastrous for the recipient. Consequently, eye banks often quarantine corneas for 10 days or more before passing them for grafting. This period, though detrimental to the endothelial cell density of the delivered cornea, is necessary to detect contamination using conventional microbiological methods. The authors previously validated the use of a pair of aerobic and anaerobic blood bottles for sensitive and rapid detection of bacteria. To allow a short quarantine period, it remained only to optimise detection of fungi. The authors aimed to compare sensitivity and rapidity of fungal contamination detection by three methods: blood bottles, Sabouraud, and daily visual inspection of the organ culture medium. METHODS: Four inocula (10(6), 10(4), 10(2), 10 colony forming unit (CFU) per ml) of 11 fungi (Candida albicans, C tropicalis, C glabrata, Saccharomyces cerevisiae, Rhodotorula rubra, Cryptococcus neoformans, Fusarium oxysporum, Aspergillus niger, A fumigatus, A flavus, Acremonium falciforme) were inoculated in a commercial organ culture medium containing a coloured pH indicator (CorneaMax, Eurobio, Les Ulis, France). The real live fungal inoculum was verified immediately after inoculation. After 48 hours at 31 degrees C, samples of the contaminated media were inoculated in three blood bottles: Bactec Aerobic/F, Bactec Mycosis IC/F, and Bactec Myco/F Lytic (Becton Dickinson, Le Pont de Claix, France), then placed in a Bactec 9240 rocking automat, and in four Sabouraud media (solid and liquid, 28 degrees C and 37 degrees C) with daily observation. Contaminated organ culture media were also checked daily for any change in turbidity and/or colour. Experiments were performed in triplicate. RESULTS: Mycosis IC/F and Myco/F Lytic bottles were neither faster nor more sensitive than the aerobic bottle. The three methods were positive for all inocula, even the lowest (viable inoculum below 10 CFU/ml for each fungus). Contamination was detected within 24 hours by the aerobic bottles in 91% (40/44), by Sabouraud in 98% (43/44) (no significant difference) and by visual inspection in 66% of cases (29/44) (p<0.001 with the two others). Maximum times to detection were 46, 48 and 72 hours respectively. CONCLUSION: This study further counters the preconception that fungal contamination is hard to detect in corneal organ culture media. This study is the last step in validating the use of a pair of blood bottles for the sterility testing of organ culture media, this time for fungi. Their use should make it possible to shorten microbiological quarantine and thus deliver corneas with higher endothelial cell density, without increasing the risk of recipient contamination.

Cornea↗
PubMed2003

[Optimizing microbiological controls of corneal organ culture media].

BACKGROUND/AIMS: To compare the efficiency of an automated method using blood bottles with conventional microbiological tests for controlling sterility in cornea organ culture media. METHODS: Two complementary studies were conducted. Experimental study: standard organ culture media were contaminated with four different inocula of 14 bacteria and 3 fungi. The bactericidal activity of organ culture media were evaluated after 48 hours of incubation at 31C. Observational study: 357 samples of organ culture media were collected over 1 year in our cornea bank. For both studies, media were inoculated in three blood bottles (aerobic, anaerobic, fungal) placed in an automat with automated detection every 10 minutes, and in three conventional microbiological media as a control. Changes in organ culture medium color and growth on conventional broth were checked daily by visual inspection. All samples were observed experimentally for 14 days. The sensitivity and rapidity of contamination detection were compared across the three methods: blood bottles, conventional method, and visual inspection of medium color. RESULTS: Experimental study: organ culture medium eradicated five bacteria: S. pneumoniae, B. catarrhalis, E. coli, P. acnes and H. influenzae. For the others, (Methicillin-resistant S. aureus, Methicillin-sensitive S. aureus, S. epidermidis, S. haemolyticus, P. aeruginosa, A. baumannii, B. subtilis, K. pneumoniae, E. faecalis, C. albicans, C. kruzei, A. fumigatus) the blood bottle method, the conventional microbiological method, and the visual inspection detected microbiological growth respectively in 100%, 76.5%, and 70% of cases. Mean detection time using blood bottles was 15.1 hours (standard deviation, 13.8; range, 2-52). In cases of detection by the blood-bottle method and the conventional method, the former was always faster: 95.5% versus 65.2% detection within 24 hours (p=0.022). Observational study: the global contamination rate was 8% (29/357 analysis). The gain in sensitivity with blood bottles was 25% compared with the conventional method. Five bacteria (three coag. neg Staphylococcus, one E. faecalis, one P. paucimobilis) were detected only by the blood bottles. In addition, these were always detected more quickly with, respectively, 66.6% versus 26.6% detection with 24 hours (p=0.028). CONCLUSIONS: Blood bottles detect contaminations of cornea organ culture media more efficiently and faster than conventional microbiological methods. They make it possible to reduce the quarantine period with an equally high security level. Consequently, they should be recommended in cornea preservation guidelines.

Bacteria↗
PubMed2002

Sensitivity and rapidity of blood culture bottles in the detection of cornea organ culture media contamination by bacteria and fungi.

AIMS: To test the bactericidal activity of standard organ culture medium, and to compare the sensitivity and rapidity of blood culture bottles with conventional microbiological methods for detection of bacteria and fungi inoculated in a standard cornea organ culture medium. METHODS: The bactericidal activity of contaminated standard organ culture medium containing 100 IU/ml penicillin, 0.1 mg/ml streptomycin, and 0.25 micro g/ml amphotericin B was evaluated after 48 hours of incubation at 31 degrees C with five inocula of 14 bacteria. Two yeasts (Candida spp) and one Aspergillus were also tested. Contaminated media were then inoculated in three blood bottles (aerobic, anaerobic, fungal) placed in a Bactec 9240 automat; three conventional microbiological broths were the control. Changes in colour of organ culture medium and growth on conventional broth were screened daily by visual inspection. The sensitivity and rapidity of detection of contamination were compared between the three methods: blood bottle, conventional, and visual. RESULTS: Organ culture medium eradicated five bacteria irrespective of the starting inoculums: Streptococcus pneumoniae, Branhamella catarrhalis, Escherichia coli, Propionibacterium acnes, and Haemophilus influenzae. For micro-organisms where the medium was ineffective or bactericidal only (methicillin resistant Staphylococcus aureus, methicillin sensitive Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus haemolyticus, Pseudomonas aeruginosa, Acinetobacter baumannii, Bacillus subtilis, Klebsiella pneumoniae, Enterococcus faecalis, Candida albicans, Candida kruzei, Aspergillus fumigatus), the blood bottle, conventional, and visual methods detected microbial growth in 100%, 76.5%, and 70% of cases respectively. Mean detection time using blood bottles was 15.1 hours (SD 13.8, range 2-52). In cases of detection by the blood bottle method and the conventional method, the former was always faster: 95.5% against 65.2% detection within 24 hours (p=0.022) respectively. CONCLUSIONS: Blood bottles detect more efficiently and more rapidly a wider range of bacteria and fungi than the conventional microbiological method and the visual inspection of organ culture media.

Bacteria↗
PubMed2001

Evaluation of BacT/Alert 3D liquid culture system for recovery of mycobacteria from clinical specimens using sodium dodecyl (lauryl) sulfate-NaOH decontamination.

A total of 52 mycobacterial isolates were recovered from 1,197 clinical specimens decontaminated by a sodium dodecyl (lauryl) sulfate (SDS)-NaOH protocol. Of these, 94% were recovered with the BacT/Alert 3D system (Organon Teknika, Durham, N.C.) and 79% were recovered on Löwenstein-Jensen (LJ) medium. Mean times to detection of organisms of the Mycobacterium tuberculosis complex (n = 47) were 22.8 days with LJ medium and 16.2 days with the system. The BacT/Alert 3D system is a rapid and efficient detection system which can be used with an SDS-NaOH decontamination procedure.

Bacteriological Techniques↗
PubMed2001

Use of a pair of blood culture bottles for sterility testing of corneal organ culture media.

AIMS: To test the effectiveness and rapidity of a pair of blood culture bottles in the diagnosis of bacterial and fungal contamination of corneal organ culture media. METHODS: 761 microbiological analyses of storage media (Inosol and Exosol, Opsia, Toulouse, France), sampled in all phases of the organ culture at 31 degrees C of 410 consecutive corneas, were analysed. Each medium was inoculated in a pair of Bactec Plus Aerobic/F and Bactec Lytic/10 Anaerobic/F blood bottles and placed in a Bactec 9240 incubator for 14 days at 37 degrees C and in a Sabouraud broth at 20 degrees C. Changes in colour or turbidity of storage media were evaluated daily at the corneal bank. Recipients were screened post-graft for infectious signs. RESULTS: Overall contamination rate was 2.4% (18/761). Contamination was detected in less than 1 day in 78% (14/18) and less than 2 days in 94% (17/18). Positivity of the microbiological controls of starting media preceded changes medium colour in 10 out of 14 cases. Bactec blood bottles allowed detection of bacteria as well as yeasts. CONCLUSION: The use of a pair of Bactec blood culture bottles appears reliable for the rapid diagnosis of a wide range of microbiological contaminations of organ cultured corneas during banking.

Bacteria↗
PubMed1995

Acinetobacter baumannii outbreak isolates characterized by three typing methods.

Forty-two strains of Acinetobacter baumannii were isolated from 15 patients hospitalized in a French intensive care unit. An epidemiological study based on the typing of these isolates was carried out using biotyping, antibiotyping, and ribotyping to recognize the transmission of multiresistant strains by transfer of a patient from one hospital to another. Fifteen strains from the outbreak (1 strain for each patient), five Acinetobacter baumannii strains isolated before the outbreak in Bellevue Hospital (St. Etienne), and five strains isolated in Cochin Hospital (Paris) were included. The three methods gave a good correlation: the epidemic strains had the same antibiotic resistance pattern, the same biotype, and the same ribotypes obtained with three different endonucleases.

Acinetobacter↗
PubMed1993

[Survey with three epidemiological markers after 22 cases of diarrhea caused by Clostridium difficile in a geriatric hospital].

In a geriatric hospital of Saint-Etienne (Charité), among 153 patients having presented a nosocomial diarrhea from September 1990 to August 1991 Clostridium difficile (C.d.) has been isolated in 22 cases. Two of the nine units of the hospital had the highest incidence rates: 4.6 and 3.7%. In the faeces of 16 patients, C.d. was toxinogenic. In all cases, except one, antibiotic preceded diarrhea. Amoxicillin + clavulanic acid treatment was the most frequently responsible (65%). For detecting an eventual outbreak, several epidemiologic markers were evaluated: Clindamycin MIC, protein profiles, serotyping. Clindamycin susceptibility differentiated two Cd. types, but has no epidemiologic value. Protein profiles, performed by SDS-Page, individualized 6 different profiles, but 10 strains gave no classifiable profiles. Serotyping, applied by M. Delmée, appeared as the most interesting marker. Inquiry allowed to eliminate an outbreak but revealed two episodes of cross contaminations in the 3 units, 2 of them having the highest incidence rates. Markers proved persistence of the same C.d. strain in some patients who were correctly treated by metronidazole.

Aged↗
PubMed1993

[Evaluation of three automated blood culture systems. Bio Argod, Bact T/Alert, bactec NR-860].

In 1991 and 1992, three automated blood culturing systems were successively assessed ("Diagnostics Pasteur" Bio Argos: 1,120 Vials, "Organon Teknika" BacT/Alert: 1,400 vials and "Becton Dickinson" bactec NR-860: 2,146 standard vials 6 and 7 and 2,360 resin vials 26 and 27), and compared with the conventional system (C) (Roche aerobic BHI-S Liquoîd, and Diagnostics Pasteur anaerobic prereduced Shaedler). Duplicate blood cultures were collected in various hospital services. They were processed over a 7-day period by the automated instruments and were incubated for 10 days using conventional techniques. The percentage of positivity (clinically significant results) obtained with the automated instruments was similar to that obtained with conventional techniques. Bio Argos: 3.4 p. cent vs 3.8 p. cent with C, BacT/Alert: 3.9 p. cent vs 3.5 p. cent, Bactec standard 6 and 7 vials: 5.6 p. cent vs 6.4 p. cent, and resin 26 and 27: 4.2 p. cent vs 3.1 p. cent. A better sensitivity was found with Bactec resin 26 and 27 vials when compared to C for Staphylococcus aureus (22 p. cent of S. aureus strains were isolated only with resin vials 26 and 27). False positives were as follow: 0.36 p. cent for BacT/Alert, 2.1 p. cent for Bio Argos and 3.5 p. cent for Bactec. The fastest detection rate was observed with the instrument which shakes the vials continuously (BacT/Alert): 73.6 p. cent of positive vials were detected on the day the vials were received at the laboratory. Ninety-four percent of the Bactec resin 26 and 27 positive vials, 90.6 p. cent of the BacT/Alert positive vials, 84 p. cent of the Bactec 6 and 7 positive vials and 73.7 p. cent of the Bio Argos positive vials were detected within twenty-four hours.

Bacteria, Aerobic↗