Candidemia in patients with hematologic malignancies in the era of new antifungal agents (2001-2007): stable incidence but changing epidemiology of a still frequently lethal infection

Abstract

Background: The incidence, epidemiology, Candida species distribution, resistance patterns, and outcome of candidemia in high-risk hematologic malignancy and/or stem cell transplantation patients have not been extensively described since the introduction of new antifungal agents.

Methods: In this retrospective study, the authors reviewed the medical records and microbiologic data of hematologic malignancy patients with candidemia at The University of Texas M. D. Anderson Cancer Center from March 2001 to February 2007.

Results: The authors analyzed 173 episodes of candidemia (170 patients), 125 (72%) of which were breakthrough cases after prior antifungal agents, mainly fluconazole (28 [22%]), caspofungin (25 [20%]), and voriconazole (18 [14%]). The incidence of candidemia (per 100,000 inpatient days) remained relatively stable, from 13.9 in 2001 to 19.2 in 2006. However, compared with the findings of previous studies at the authors' institution, the frequency of Candida glabrata and C. krusei infection decreased (to 5% and 17%, respectively) and C. parapsilosis (24%) and C. tropicalis (21%) increased. C. parapsilosis fungemia was associated with prior caspofungin use (P<.001). The overall 30-day crude mortality rate was 38%, and the attributable mortality rate was 19%, similar to previous findings at the authors' institution. The Candida species associated with the highest mortality rate was C. glabrata.

Conclusions: Despite the widespread use of antifungal prophylaxis and the introduction of new antifungal agents, the incidence and associated mortality rates of candidemia remained stable in high-risk hematologic malignancy patients. However, its epidemiological characteristics have shifted, with C. parapsilosis and C. tropicalis becoming more common.