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International audience; Objective of the study. - Study of the spatio-temporal fungal colonization in a new medical mycology laboratory. Methods. - A 17-month survey of airborne fungal contamination was conducted in a new medical mycology laboratory at a tertiary care university hospital. This survey was implemented at three different periods: before the new premises were occupied (period A), during the move into the new laboratory (period B) and after resumption of the mycological activities in these new premises (period C). Results. - During period A, the airborne fungal load ranged from 2.3 to 6 cfu/m(3). The most frequently recovered airborne fungi were Penicillium spp. (75 to 100%). During period B, a dramatic increase in Penicillium chrysogenum conidia was observed in the air of the new laboratory (40 to 160 cfu/m(3)). During period C, the fungal load ranged from 4.5 to 8.4 cfu/m(3). Penicillium was the most common genus identified in rooms of the laboratory where no filamentous fungi were handled, while Aspergillus was clearly the predominant genus (78%) in the room dedicated to the culture of filamentous fungi. Conclusions. - We suggest that the specific fungal ecology in air of the room dedicated to the culture of filamentous fungi is due to the handling of a large number of medical strains of A. fumigatus.; Objectif de l’étude : Étude spatio-temporelle de la colonisation fongique dans un nouveau laboratoire de mycologie médicale. Méthodes : Durant 17 mois, l’aérocontamination fongique a été évaluée dans trois pièces d’un nouveau laboratoire de mycologie médicale d’un centre hospitalo-universitaire. Cette surveillance a été programmée à trois périodes différentes : avant l’occupation des nouveaux locaux (période A), durant l’emménagement dans le nouveau laboratoire (période B) et après la reprise des activités de mycologie médicale dans ces nouveaux locaux (période C). Résultats : Durant la période A, la charge fongique dans l’air était comprise entre 2,3 et 6 ufc/m3. Le micromycète le plus fréquemment isolé a été Penicillium spp. (75 à 100 %). Durant la période B, une très forte augmentation de la charge en conidies de Penicillium chrysogenum a été observée dans l’air du nouveau laboratoire (40 à 160 ufc/m3). Durant la période C, la charge fongique a été comprise entre 4,5 et 8,4 ufc/m3. Penicillium a été le genre le plus fréquemment identifié dans les deux pièces du laboratoire où aucun champignon filamenteux n’est manipulé, alors qu’Aspergillus a clairement été le genre prédominant (78 %) dans la pièce consacrée à la culture des champignons filamenteux. Conclusions : Nous suggérons que la manipulation d’un grand nombre de souches médicales d’Aspergillus est à l’origine de l’écologie spécifique qui existe dans la pièce du laboratoire destinée à la manipulation des champignons filamenteux.

In clinical laboratories, isolation of Candida species is generally based on the culture of specimens on Sabouraud dextrose agar. This strategy does not allow species identification on primary culture and makes it difficult to detect mixed cultures. Chromogenic media contain substrates that react specifically with different Candida species, and partly overcome these difficulties. Objectives The aim of this study was to compare two chromogenic media: (i) CandiSelect4 (C4), a new medium developed for direct identification of C. albicans and presumptive identification of C. krusei , C. tropicalis and C. glabrata (ii) CHROMagar Candida (CH), a medium licensed for direct identification of C. albicans , and presumptive identification of C. tropicalis and C. krusei , and employed in our laboratory since 2002. Materials and methods Altogether, 533 clinical specimens were seeded on both media. Identification on C4 was compared to that achieved on CH, API 32 C test or an in-house C. glabrata rapid identification test. Results Discrepant positive cultures occurred in 16 samples and were shared equally between C4 and CH. The ability of both media to detect associations was equivalent, with 34 associations identified with C4 and CH. No discrepancy was observed with respect to identification of C. albicans . C4 identified six of six C. krusei , but false-negative identification of C. tropicalis occurred in 2/11 cases and false-positive identification of C. glabrata occurred in 2/34 cases. Conclusions The overall performance of C4 and CH appeared almost identical during a two-month comparison in the clinical mycology setting.

International audience; An 18-month survey of indoor fungal contamination was conducted in one haematology unit during a period of construction work. Air was sampled with a portable Air System Impactor and surfaces with contact Sabouraud plates. During this survey the mean concentration of viable fungi in air was 4.2 cfu/m(3) and that for surfaces was 1.7 cfu/plate. At the beginning of construction work, there were increases in airborne fungal spores (from 3.0 to 9.8 cfu/m(3)) in the unit, but concentrations did not exceed 10 cfu/m(3) during the 18-month period. The most frequently recovered airborne fungi were Penicillium spp. (27-38%), Aspergillus spp. (25%) and Bjerkandera adusta, a basidiomycete identified with molecular tools (7-12%). Blastomycetes accounted for more than 50% of the fungal flora on surfaces. Investigating the impact of a new air-treatment system (mobile Plasmair units), there were significant reductions in fungal contamination for the Plasmer -treated rooms, and in these rooms we observed the same level of fungal load whether construction work was in progress or not.

This study was undertaken to identify prescribing policies likely to favour or limit fluconazole resistance within a clinical department. Fluconazole exposure within the infectious diseases and clinical haematology units was investigated, and data were compared with in vitro susceptibility of Candida albicans isolates obtained in these units. Fluconazole utilization was determined by the number of fluconazole treatment-days per 100 hospitalization days (penetration index). In the infectious diseases unit, separate evaluations for low-dose fluconazole (50mg) prescribed as intermittent or prolonged treatment, and for higher-dosing schedules (fluconazole 200mg) were made. Susceptibility of C. albicans isolates was surveyed in a broth microdilution assay by measuring the inhibitory concentration 50% (IC 50 ). The penetration index (PI) for fluconazole 50mg declined from 1992 to 1977 in infectious diseases ( P = 0.0048). In the meantime, total usage of fluconazole increased, due to increased prescribing of fluconazole 200mg ( P = 0.0724). The IC 50 of C. albicans isolates tested in infectious diseases decreased between 1994 and 1996 from 7.33mg/ml to 1.64mg/ml ( P = 0.0075). In clinical haematology, declines in C. albicans IC 50 and fluconazole PI were not significant ( P = 0.35 and P = 0.07, respectively). These data suggest that prolonged or repeated exposure to low-dose fluconazole, rather than total cumulative use, was associated with fluconazole resistance in the infectious diseases unit. Moreover, restoration of a normal ecology was observed when low-dose prolonged or intermittent prescriptions were reduced.

Resume Une methode de culture en plaques de microtitration a ete utilisee pour etudier la sensibilite au fluconazole de levures isolees de prelevements oropharynges (n = 108) ou d'hemocultures (n = 56) et comparer le profil des souches isolees chez des patients recevant ou non une chimioprophylaxie par fluconazole. Le parametre mesure, la concentration inhibitrice 50 % (CI 50), est la concentration de fluconazole reduisant de 50 % la turbidite d'une suspension de la levure etudiee apres 48 heures de culture. Les CI 50 moyennes ont pu etre calculees pour les especes fungiques suivantes : Candida albicans, 1,26 μg/ml; C. parapsilosis, 2,38 μg/ml; C. glabrata, 4,54 μg/ml; C. krusei, 12,58 μg/ml. Neuf des 108 souches de C. albicans ont presente une CI 50 superieure ou egale a 4 μg/ml, et les CI 50 moyennes des souches de C. albicans isolees chez des patients recevant ou non du fluconazole au moment du prelevement etaient de 3,11 et 0,93 μg/lm respectivement (p