This Article Full Text Full Text (PDF) Other Versions of this Article: JCM.01776-06v1 45/1/173    most recent 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 Binnicker, M. J. Articles by Wengenack, N. L. Search for Related Content PubMed PubMed Citation Articles by Binnicker, M. J. Articles by Wengenack, N. L.

 Previous Article  |  Next Article 

Journal of Clinical Microbiology, January 2007, p. 173-178, Vol. 45, No. 1
0095-1137/07/$08.00+0     doi:10.1128/JCM.01776-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

Detection of Coccidioides Species in Clinical Specimens by Real-Time PCR

Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic and Mayo Clinic College of Medicine, Rochester, Minnesota 55905,¹ Department of Laboratory Medicine and Pathology, Mayo Clinic Arizona, Scottsdale, Arizona 85259²

Received 28 August 2006/ Returned for modification 13 September 2006/ Accepted 16 October 2006

Coccidioides spp. are dimorphic fungal pathogens endemic to the semiarid regions of North, Central, and South America. Currently, direct smear and culture are the most common means of identifying Coccidioides spp. While these methods offer relatively sensitive and specific means of detecting Coccidioides spp., growth in culture may take up to 3 weeks, potentially delaying the diagnosis and initiation of appropriate antifungal therapy. In addition, growth of the organism represents a significant safety risk to laboratory personnel. The need for a rapid and safe means of diagnosing coccidioidomycosis prompted us to develop a real-time PCR assay to detect Coccidioides spp. directly from clinical specimens. Primers and fluorescent resonance energy transfer (FRET) probes were designed to target the internal transcribed spacer 2 region of Coccidioides. The assay's limit of detection is below 50 targets per reaction. An analysis of 40 Coccidioides sp. clinical isolates grown in culture demonstrated 100% sensitivity of the assay. A cross-reactivity panel containing fungi, bacteria, mycobacteria, and viruses was tested and demonstrated 100% specificity for Coccidioides spp. An analysis of 266 respiratory specimens by LightCycler PCR demonstrated 100% sensitivity and 98.4% specificity for Coccidioides spp. compared with culture. Analysis of 66 fresh tissue specimens yielded 92.9% sensitivity and 98.1% specificity versus those of the culture method. The sensitivity of the assay testing 148 paraffin-embedded tissue samples is 73.4%. A rapid method for the detection of Coccidioides spp. directly from clinical material will greatly assist in the timely diagnosis and treatment of patients, while at the same time decreasing the risk of accidental exposure to laboratory personnel.

Published ahead of print on 15 November 2006.

This article has been cited by other articles:

• Vollmer, T., Stormer, M., Kleesiek, K., Dreier, J. (2008). Evaluation of Novel Broad-Range Real-Time PCR Assay for Rapid Detection of Human Pathogenic Fungi in Various Clinical Specimens. J. Clin. Microbiol. 46: 1919-1926 [Abstract] [Full Text]