Antifungal Susceptibilities and Distribution of Candida Species Recovered from Blood Cultures over an 8-Year Period

Chae, Myoung Jong; Shin, Jong Hee; Cho, Duck; Kee, Seung Jung; Kim, Soo Hyun; Shin, Myung Geun; Shin, Dong Hyeon; Jung, Sook In; Suh, Soon Pal; Ryang, Dong Wook

Abstract

BACKGROUND
Nosocomial candidemia has increased over the past 2 decades. The rank order of occurrence and antifungal resistance profiles of the various species of Candida causing candidemia is important in establishing empiric treatment protocols. METHODS: We investigated antifungal susceptibilities and distribution of Candida species recovered from blood cultures over an 8-year period in Chonnam National University Hospital. The results obtained from the period 1994 through 1997 (period 1) were compared with those from the period 1998 through 2001 (period 2). Minimal inhibitory concentrations (MICs) of amphotericin B, fluconazole and itraconazole for each isolate were determined by the NCCLS broth microdilution method. RESULTS: During an 8-year period, 805 strains of Candida species were isolated from 290 patients. In period 1, the Candida species recovered most frequently from candidemic patients was C.albicans(29.5%), followed by C. parapsilosis (25.9%) and C. tropicalis (18.8%). In period 2, C. parapsilosis (31.5%) was the most common species, followed by C. albicans (23.6%), and C.glabrata (14.0%). These data, compared to those of period 1, indicate a variation in species distribution, with the proportions of C. glabrata increasing by 10.0% (P<0.005). MIC50 of amphotericin B, fluconazole and itraconazole for each species did not change appreciably during the two periods. However, resistance to fluconazole (>or=64 microgram/mL) and itraconazole (>or=1 microgram/mL) was observed more frequently in period 2 (8.0% and 20.9%, respectively) than in period 1 (2.0% and 7.0%, respectively)(P<0.05). CONCLUSIONS: These data showed that MICs of amphotericin B, fluconazole and itraconazole for each species did not change during the 8-year span, but azole resistant Candida species such as C. glabrata, increased in the latter four years (period 2).