A total of 38 isolates of Candida albicans were collected from clinical specimens and tested for minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) of amphotericin B, flucytosine and fluconazole. For amphotericin B and flucytosine all patients had isolates with MICs < or = 2 micrograms ml-1 and < or = 8 micrograms ml-1 respectively. For fluconazole all but two isolates had MICs < or = 16 micrograms ml-1. In vitro susceptibility testing remains problematic since standardized methods have not been established and the susceptibility and resistance ranges of MIC/MFC values still have to be defined in relation to in vivo data. Nevertheless, these results indicate that topical application of amphotericin B (more than 1 kg of amphotericin B per year at an intensive care unit performing selective digestive tract decontamination on certain trauma patients) had no major impact on the resistance patterns of C. albicans. In contrast, in this study both fluconazole-resistant isolates were from AIDS patients who were known to have received fluconazole therapy. Treatment with fluconazole--quite common in patients with AIDS--may produce resistant fungal isolates.