PCR-Based Methods for the Diagnosis of Invasive Candidiasis: Are They Ready for Use in the Clinic?
Purpose of Review
We review the performance of Candida PCR and the T2Candida panel (T2Biosystems, Lexington, MA) in diagnosing invasive candidiasis, consider how these tests may be incorporated into patient care, and determine if they are ready to be used in the clinic.
PCR and T2Candida sensitivity/specificity for diagnosing candidemia are ~ 90%/90% and ~ 90%/98%, respectively. Limited data for intra-abdominal candidiasis suggest PCR sensitivity of ~ 85–90%, but specificity has varied from 33 to 97%. T2Candida data are lacking for infections other than candidemia.
PCR and T2Candida will have the greatest value if their use is restricted to cases in which positive and negative predictive values differ in a clinically meaningful way from the pre-test likelihood. Studies are needed to establish that patient care and stewardship strategies incorporating Candida PCR or T2Candida improve patients’ outcomes, reduce unnecessary antifungal usage, limit emergence of resistance, and are cost-effective. The development and validation of standardized PCR assays is a top priority.
KeywordsCandidiasis Candidemia PCR T2Candida Diagnostic Bayesian
Compliance with Ethical Standards
Conflict of Interest
Drs. Clancy and Nguyen have served as principal investigators for clinical trials sponsored by T2 Biosystems and ViraCor Eurofins. Dr. Clancy has spoken at symposia sponsored by T2 Biosystems.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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