A 3-year study of resistance of Candida pathogens obtained from patients with fungaemia with emphasis on new antifungal agents

Abstract number: p1228

Koutsoukou  A., Stylianakis  A., Tsiplakou  S., Tachtatzis  M., Tsakona  E., Vourtsi  A., Sideri  A.

Objective: 

The aim of the present study was to examine the resistance of Candida species to amphotericin-B, fluconazole, itraconazole, 5-flucytocine and to the new antifugal agents voriconazole and caspofungin.

Methods: 

152 non duplicated Candida species, isolated from blood cultures (Bactec, Becton Dickinson) over a 3 year period (2003–2005), were identified and MIC values were determined. Identification was performed by VITEK II automated system (Biomerieux) and confirmed by the API 20C AUX (Biomerieux). MICs for amphotericin-B, fluconazole, itraconazole and 5- flucytocine were determined by ATB fungus 2 (Biomerieux). For the new agents voriconazole and caspofungin, MICs were defined by E-test (AB Biodisk, Solna, Sweden) and confirmed by broth microdilution method, according to NCCLS criteria (document M 27-A).

Results: 

Candida parapsilosis was the predominant species (64%) followed by Candida albicans (24%), Candida tropicalis (8%), Candida glabrata (2%), Candida krusei (1%). 77 (50%) strains were resistant to itraconazole 44 (33%) strains were resistant to fluconazole, 7 (5%) strains were resistant to 5-flucytocine while no strain was found resistant to amphotericin-B. The MICs of caspofugin were between 0.25–2 mg/ml and the MICs of voriconazole were less than 1 mg/ml. Only 2 strains of Candida parapsilosis had MICs higher than 2 mg/ml to voriconazole and would be classified as resistant to the drug.

Conclusions: 

Our findings show that fungemia in our hospital is caused mainly by Candida parapsilosis. Moreover Candida blood stream infections had high-rates of resistance to itraconazole and fluconazole in contrast to voriconazole. All Candida strains were susceptible to caspofungin. Also, no resistance was observed to amphotericin-B which remains the more active antifungal agent in common use.