[Optimization of sensitivity tests to ketoconazole. Value of experience planning in the choice of a medium]

Using factorial design, the authors evaluate the factors which influence in vitro, the anti-fungal activity of ketoconazole against a strain of Candida albicans (CBS 562). With the four mediums most frequently used, (Sabouraud, Casitone, MEM, YNB) they precise the results concerning inoculum, pH, incubation temperature, growth time, serum concentration, and shaking. This method allows the evaluation of each factor in optimal conditions of test. In most cases, the best results are obtained with a 10(4) UFC/ml inoculum, a pH = 7, in absence of serum and without shaking. The influence of temperature is very small. In these conditions, the Casitone medium seems the most satisfactory.