Effect of reduced oxygen on the antifungal susceptibility of clinically relevant aspergilli.

The influence of hypoxia on the in vitro activities of amphotericin B, azoles, and echinocandins against Aspergillus spp. was evaluated by comparing MICs, minimal fungicidal concentrations (MFCs), and epidemiological cutoffs (ECOFFs). Changes of MIC distributions due to hypoxia largely depend on the method, the species, and the growth ability under hypoxia. The activities of antifungals were not significantly altered under hypoxia, except for Aspergillus terreus, for which the activity changed from fungicidal to fungistatic.