This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Magill, S. S. Articles by Merz, W. G. Search for Related Content PubMed PubMed Citation Articles by Magill, S. S. Articles by Merz, W. G.

 Previous Article  |  Next Article 

Journal of Clinical Microbiology, February 2006, p. 529-535, Vol. 44, No. 2
0095-1137/06/$08.00+0     doi:10.1128/JCM.44.2.529-535.2006
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

Triazole Cross-Resistance among Candida spp.: Case Report, Occurrence among Bloodstream Isolates, and Implications for Antifungal Therapy

Infectious Diseases Division, Department of Medicine,¹ Microbiology Division, Department of Pathology,² Department of Surgery, Johns Hopkins University School of Medicine and Johns Hopkins Hospital, Baltimore, Maryland³

Received 12 August 2005/ Returned for modification 14 October 2005/ Accepted 16 November 2005

Candida spp. are common causes of bloodstream infections among hospitalized patients. Fluconazole (FLC) remains a first-line therapy for candidemia; and voriconazole (VRC), an expanded-spectrum triazole, was recently approved for the treatment of candidemia in nonneutropenic patients. In vitro studies have suggested that VRC has potent activity against Candida spp. with reduced susceptibilities to FLC. We present a case report of invasive candidiasis and candidemia due to a Candida glabrata isolate that developed resistance to all currently available triazole antifungals after a course of FLC treatment. This case prompted us to determine the frequency of cross-resistance among bloodstream Candida isolates collected during a recent 12-month period at a large, academic medical center. FLC MICs were determined for 125 of 153 isolates (81.7%). Thirty of 125 isolates (24%) were resistant or showed reduced susceptibilites to FLC (MICs 16 µg/ml). When 28 of these 30 isolates were tested for their VRC susceptibilities, 9 (32%) had MICs that were 2 µg/ml. Five of these nine isolates were C. glabrata, two isolates were Candida tropicalis, one isolate was Candida albicans, and one isolate was Candida parapsilosis. All five Candida krusei isolates tested had VRC MICs 0.5 µg/ml. These data have prompted the introduction of reflexive FLC susceptibility testing of first bloodstream Candida isolates at our institution. The case report and our data also suggest that VRC should be avoided as initial therapy in unstable patients with invasive candidiasis, particularly in the setting of prior azole exposure. Studies are needed to define the clinical significance of in vitro resistance to the newer antifungal agents.

This article has been cited by other articles:

• Tumbarello, M., Sanguinetti, M., Trecarichi, E. M., La Sorda, M., Rossi, M., de Carolis, E., de Gaetano Donati, K., Fadda, G., Cauda, R., Posteraro, B. (2008). Fungaemia caused by Candida glabrata with reduced susceptibility to fluconazole due to altered gene expression: risk factors, antifungal treatment and outcome. J Antimicrob Chemother 0: dkn381v1-7 [Abstract] [Full Text]  
• Pfaller, M. A., Diekema, D. J., Procop, G. W., Rinaldi, M. G. (2007). Multicenter Comparison of the VITEK 2 Antifungal Susceptibility Test with the CLSI Broth Microdilution Reference Method for Testing Amphotericin B, Flucytosine, and Voriconazole against Candida spp.. J. Clin. Microbiol. 45: 3522-3528 [Abstract] [Full Text]  
• Shin, J. H., Chae, M. J., Song, J. W., Jung, S.-I., Cho, D., Kee, S. J., Kim, S. H., Shin, M. G., Suh, S. P., Ryang, D. W. (2007). Changes in Karyotype and Azole Susceptibility of Sequential Bloodstream Isolates from Patients with Candida glabrata Candidemia. J. Clin. Microbiol. 45: 2385-2391 [Abstract] [Full Text]  
• Collins, C. D., Eschenauer, G. A., Salo, S. L., Newton, D. W. (2007). To Test or Not To Test: a Cost Minimization Analysis of Susceptibility Testing for Patients with Documented Candida glabrata Fungemias. J. Clin. Microbiol. 45: 1884-1888 [Abstract] [Full Text]  
• Pfaller, M. A., Diekema, D. J., Gibbs, D. L., Newell, V. A., Meis, J. F., Gould, I. M., Fu, W., Colombo, A. L., Rodriguez-Noriega, E., and the Global Antifungal Surveillance Group, (2007). Results from the ARTEMIS DISK Global Antifungal Surveillance Study, 1997 to 2005: an 8.5-Year Analysis of Susceptibilities of Candida Species and Other Yeast Species to Fluconazole and Voriconazole Determined by CLSI Standardized Disk Diffusion Testing. J. Clin. Microbiol. 45: 1735-1745 [Abstract] [Full Text]  
• Pfaller, M. A., Diekema, D. J., Procop, G. W., Rinaldi, M. G. (2007). Multicenter Comparison of the VITEK 2 Yeast Susceptibility Test with the CLSI Broth Microdilution Reference Method for Testing Fluconazole against Candida spp.. J. Clin. Microbiol. 45: 796-802 [Abstract] [Full Text]  
• Pfaller, M. A., Diekema, D. J. (2007). Epidemiology of Invasive Candidiasis: a Persistent Public Health Problem. Clin. Microbiol. Rev. 20: 133-163 [Abstract] [Full Text]  
• Pfaller, M. A., Messer, S. A., Boyken, L., Rice, C., Tendolkar, S., Hollis, R. J., Diekema, D. J. (2007). Use of Fluconazole as a Surrogate Marker To Predict Susceptibility and Resistance to Voriconazole among 13,338 Clinical Isolates of Candida spp. Tested by Clinical and Laboratory Standards Institute-Recommended Broth Microdilution Methods. J. Clin. Microbiol. 45: 70-75 [Abstract] [Full Text]  
• Isham, N., Ghannoum, M. A. (2006). Determination of MICs of Aminocandin for Candida spp. and Filamentous Fungi. J. Clin. Microbiol. 44: 4342-4344 [Abstract] [Full Text]  
• Panackal, A. A., Gribskov, J. L., Staab, J. F., Kirby, K. A., Rinaldi, M., Marr, K. A. (2006). Clinical Significance of Azole Antifungal Drug Cross-Resistance in Candida glabrata.. J. Clin. Microbiol. 44: 1740-1743 [Abstract] [Full Text]