Trends in species distribution and susceptibility to fluconazole among blood stream isolates of Candida species in the United States

National surveillance of blood stream infections (BSI) attribut able to Can dida spp. has been limited to date. Recent studies have suggested an increa se in the proportion of BSI attributable to non-Candida albicans species an d have also raised concerns regarding the emergence of antifungal resistanc e among Candida spp. The increased utilization of broad-spectrum antifungal agents and the recognition of Candida spp. as prominent pathogens with the potential for developing antifungal resistance, emphasize the need for ong oing surveillance of antifungal susceptibility patterns. In this investigat ion trends in species distribution and susceptibility to fluconazole among BSI isolates of Candida spp. referred to our laboratory by United States ho spitals were evaluated over the 7-year period from 1992 to 1998. A fatal of 1579 BSI isolates from more than 50 medical centers were processed. Overal l, C. albicans accounted for 52% of isolates followed by C. glabrata (18%), C. parapsilosis (15%), C. tropicalis (11%), and C. krusei (2%). The propor tion of BSI isolates that were C. albicans ranged from 45% in 1992 to 60% i n 1998. Among the non-C. albicans isolates, C. glabrata succeeded C. paraps ilosis as the most common species beginning in 1995. Overall, the susceptib ility of all Candida species (C. albicans plus all other species) to frucon azole remained stable (MIC90, 16 mu g/mL). The fluconazole MIC90 for C. alb icans was 0.5-2.0 mu g/mL for all years studied except 1995 (8.0 mu g/mL) a nd was 1.0 mu g/mL overall. The present study suggests a continued prominen t role of C. albicans as a cause of BSI, and a constant level of susceptibi lity of Candida BSI isolates to fluconazole over 7 years. These data should serve as a baseline for future surveillance efforts for anti-fungal agents tested against yeast BSI isolates. (C) 1999 Elsevier Science Inc.