Azole and fungicide resistance in clinical and environmental Aspergillus fumigatus isolates


Ressource 1Download: REF.pdf (72.43 [Ko])
State: Public
Version: Final published version
License: Not specified
It was possible to publish this article open access thanks to a Swiss National Licence with the publisher.
Serval ID
Article: article from journal or magazin.
Azole and fungicide resistance in clinical and environmental Aspergillus fumigatus isolates
Medical Mycology
Meneau  I., Sanglard  D.
1369-3786 (Print)
Publication state
Issued date
43 Suppl 1
Journal Article
Research Support, Non-U.S. Gov't --- Old month value: May
Aspergillus fumigatus is a human pathogen but it is also a widespread filamentous fungus in the environment. A. fumigatus can therefore be exposed to antifungals used in medical and agricultural environments. Only the class of azoles is used in both of these environments (i.e. voriconazole and itraconazole in medicine; prochloraz, propiconazole or imazalil in agriculture). Exposure to azoles provides the potential for the development of resistance. Several clinical itraconazole-resistant isolates have been reported in A. fumigatus and their resistance mechanisms have been partially resolved. Since limited data exist on the susceptibility of A. fumigatus to both medical and agricultural antifungals, we undertook a drug susceptibility study including clinical (400) and agricultural (150) A. fumigatus isolates (Swiss origin). We tested azoles and also compounds of major antifungal classes used in agriculture (i.e. azoxystrobin, iprodione, benalaxyl or cyprodinil). The results showed that all A. fumigatus isolates were intrinsically resistant to iprodione, benalaxyl or cyprodinil (MIC90 > 32 microg x ml(-1)) and that azoxystrobin minimal inhibitory concentrations (MICs) showed a wide range (0.06 to 32 microg x ml(-1)). MIC ranges of azoles were compound-dependent. MIC90 for voriconazole, itraconazole, imazalil and prochloraz were within a range of 0.13 to 1 microg x ml(-1) and similar between clinical and environmental isolates, whereas propiconazole was the least active compound (MIC90: 4-8 microg x ml(-1)). Ten clinical and 36 environmental isolates with high itraconazole MIC ( > or = 2 microg x ml(-1)) were detected. In clinical isolates, no cross-resistance was observed between itraconazole and all others azoles tested. Several patterns of azole MICs were, however, observed in the environmental isolates. Unexpectedly, a single environmental isolate was voriconazole-resistant (MIC of 16 microg x ml(-1)) but still susceptible to itraconazole (MIC of 2 microg x ml(-1)). Taken together, our results demonstrate the absence of susceptibility of A. fumigatus isolates to non-azole agricultural agents and that there is little impact of azole resistance in both clinical and environmental isolates. When detected, azole resistance was compound-specific.
Aspergillosis/microbiology Aspergillus fumigatus/*drug effects/isolation & purification Azoles/*pharmacology *Drug Resistance, Fungal Environmental Microbiology Fungicides, Industrial/*pharmacology Humans Microbial Sensitivity Tests
Web of science
Open Access
Create date
25/01/2008 14:40
Last modification date
14/02/2022 7:55
Usage data