Laboratory tests of antifungal drugs

The procedures evolved in the author's laboratory over the past 20 years for the microbiological assessment of antifungal drugs are described; methods are detailed for the estimation of the sensitivity of pathogenic fungi to therapeutic agents and for the assay of those agents in body fluids. The preparation and maintenance of stock reference solutions of the drugs, the culture media used, and the incubation temperature and time are discussed. Sensitivity tests by paper disc and by liquid titration for minimal inhibitory and cidal concentrations estimated are described, and the importance of standardized initial inocula is emphasized. Two groups of assay procedures are given, the liquid dilution and the agar diffusion methods, and suitable indicator organisms for both methods are named. The paper concludes with a discussion on the problem of differential assays when two antimycotic agents are in simultaneous clinical use.