In vitro activity of voriconazole against Prototheca wickerhamii: comparative evaluation of sensititre and NCCLS M27-A2 methods of detection.

A total of 104 Prototheca wickerhamii isolates and two control strains were tested for susceptibility to voriconazole using the Sensititre YeastOne colorimetric antifungal plate and NCCLS reference method. Voriconazole was highly active against all isolates, with an MIC at which 90% of isolates were inhibited of < or = 0.5 microg/ml. Comparison of MICs obtained with the Sensititre product and the NCCLS method demonstrated agreement (100% +/- 2 log2 dilutions) between the two methods. Voriconazole may offer an option for the treatment of Prototheca sp. infections, and its efficacy should be established through clinical experience.