Emerging evidence of selection of fluconazole-tolerant fungi in surgical intensive care units

T. G. Gleason, A. K. May, D. Caparelli, B. M. Farr and R. G. Sawyer
Department of Surgery, University of Virginia, Charlottesville, USA. tgg2s@virginia.edu

OBJECTIVE: To determine whether increased use of fluconazole has coincided with a shift in the relative proportion of fluconazole-tolerant species isolated from critically ill surgical patients in 2 university hospitals. DESIGN: Microbiological data and fluconazole administration frequencies were reviewed among patients treated in the surgical intensive care units (SICUs) from January 1, 1990, through December 31, 1995. SETTING: The SICUs of the University of Virginia Medical Center, Charlottesville, and the Hospital of the University of Pennsylvania, Philadelphia. MAIN OUTCOME MEASURES: The number and species types of all fungal isolates and the number of patients treated with fluconazole for each of the 6 years were determined. RESULTS: A sharp increase in the use of fluconazole among critically ill surgical patients has occurred at both medical centers from 1990-1995. The culture results of most patients treated with fluconazole were negative for fungi (73% and 63% at the University of Virginia Medical Center and the Hospital of the University of Pennsylvania, respectively); there was a greater tendency to use fluconazole at the University of Virginia Medical Center compared with the Hospital of the University of Pennsylvania (2.2% vs 1.8% of patients admitted to the SICU received it, respectively; P = .007). There was a significant increase in the proportion of Candida glabrata isolated at the University of Virginia Medical Center (P < .01) from 1990-1995, but a similar change was not detectable at the Hospital of the University of Pennsylvania. CONCLUSIONS: These data justify concern that the increased use of fluconazole in SICUs may be promoting a shift in the fungal flora that cause nosocomial infections toward species that are more difficult to treat. Prospective studies about the use of fluconazole for prophylaxis and empirical therapy among SICU patients are warranted before its widespread use in these settings continues.