Does hydrocortisone modify the in vitro susceptibility of Aspergillus fumigatus to itraconazole and amphotericin B?
To analyse if hydrocortisone could modify the in vitro susceptibility of Aspergillus fumigatus to antifungal drugs, we developed a procedure to test the susceptibility of an A. fumigatus strain to amphotericin B and itraconazole, grown in the presence and in the absence of hydrocortisone. Conidia were germinated in the presence or the absence of hydrocortisone in Czapek medium without antifungal drug. A dilution of these cultures (5x10(3) conidia ml(-1)) was spread onto Czapek-agarose plates containing both antifungal drug and hydrocortisone. The cfu per plate were enumerated and compared. A therapeutic concentration of hydrocortisone induced a significant increase in the susceptibility to itraconazole. Conversely, the susceptibility to amphotericin B was not significantly modified when this antifungal drug was associated with hydrocortisone.
Département de Parasitologie-Mycologie Médicale et Moléculaire, CNRS UPRES-A 5082, Faculté de Médecine et de Pharmacie, Université Joseph Fourier, Grenoble I. La Tronche, France. Isabelle. Ramondenc@ujfgrenoble.fr
I
I
Ramondenc
C
C
Pinel
P
P
Ambroise-Thomas
R
R
Grillot
D000666:Amphotericin B / Q000494:pharmacology*; D000935:Antifungal Agents / Q000494:pharmacology*; D001232:Aspergillus fumigatus / Q000187:drug effects* / Q000254:growth & development; D006854:Hydrocortisone / Q000494:pharmacology*; D017964:Itraconazole / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests
D000935:Antifungal Agents; D017964:Itraconazole; D000666:Amphotericin B; D006854:Hydrocortisone