EFFECTS OF ANTIFUNGAL PRETREATMENT ON THE SUSCEPTIBILITY OF CANDIDA-ALBICANS TO HUMAN-LEUKOCYTES

The aim of this work was to measure the susceptibility of Candida albi cans pretreated for 2 or 6 h with fluconazole (Flu), ketoconazole (Ktz ), amphotericin B (AmB) and 5-fluorocytosine (5-Fc) to the fungicidal action of human polymorphic leukocytes. The influence of pretreatment was measured by comparing the delay (in hours) and reduction (log(10)) in growth of pretreated cultures in the presence of leukocytes and se rum with that of non-pretreated control cultures. Six-hour pretreatmen ts with Flu, Ktz, AmB and 5-Fc led to growth delays of 1, 3, 3 and 3 h , respectively. No significant differences were found when pretreatmen t lasted only 2 h. With respect to a reduction in growth, this was lar ger when the preincubation was 6 h, mainly for 5-Fc and AmB. 5-Fc was seen to be the most effective, followed by Ktz, AmB and finally Flu. I t may be concluded that antifungal pretreatment renders this yeast mor e susceptible to the action of leukocytes. The degree of susceptibilit y achieved is dependent on the antifungal agent employed.