Antifungal susceptibility of emerging yeast pathogens

BACKGROUND. To study the antifungal susceptibility of emerging yeast pathog ens to know their possible resistance under the need of applying a treatmen t. MATERIAL AND METHODS. We investigated the in vitro susceptibility of 69 yea st strains isolates of clinical samples, belonging to 24 different species, to amphotericin B, fluconazole, itraconazole, ketoconazole and 5-fluorocyt osine. RESULTS. Only 9 species showed susceptibility to all antifungal agents: Can dida famata, C. guillermondii, C. holmii, C. kefyr, C. pelliculosa, C. rugo sa, C. utilis, C. zeylanoides y Trichosporon cutaneum; the rest of them pre sented resistance to some antifungal agent. C. haemulonii; Pichia farinosa and Trichosporon mucoides were resistant to amphotericin B; C. haemulonii, C. inconspicua, C. lusitaniae, C. norvegensis, C. pintolepesii, C. valida, P. ohmeri, Rhodotorula glutinis, R. minuta, R. mucilaginosa and Saccharomyc es cerevisiae were resistant to azoles; Blastoschizomyces capitatus and C. lipolytica were resistant to 5-fluorocytosine. CONCLUSIONS. The resistance of emerging yeast pathogens to amphotericin B a nd 5-fluorocytosine is low, while resistance to azoles is significative, es pecially to fluconazole (36%). Many of this yeasts present problems of intr insic resistance. In yeast infections, the correct identification of specie s and the study of the in vitro susceptibility is important in order to cho ose the most adequate antifungal treatment.