Near patient detection of pathogenic candida species directly from blood and urine for rapid treatment response

Johns Hopkins University, Baltimore MD

Investigators

Abstract

ABSTRACT Fungal species are among the most common causes of nosocomial bloodstream and invasive infections in immunocompromised hosts. Mortality from candidemia can be very high, ranging from 20-40%. The global emergence of virulent multidrug resistant species such as Candida auris, with a mortality reported to be as high as 68% is particularly worrisome. Culture-based tests to detect Candida infections are slow, relatively insensitive, and may have difficulty distinguishing between C. auris and other related Candida species. Nucleic acid amplification-based Candida assays do not have the sensitivity required to detect a Candida infection directly from a patient blood sample (without pre-culture amplification) except for the T2Candida test (based on magnetic resonance technology), which is prohibitively expensive, slow, low throughput and is only able to distinguish among a limited number of Candida species. A more widely available, more rapid and user friendly, and less expensive test for fungal blood stream infections has the potential to greatly impact patient care and improve infection control. This proposal will take advantage of years of successful collaborations between the Alland laboratory and Cepheid developing point of care diagnostic assays, including new approaches to large blood volume sample processing and ultra-sensitive DNA sequence detection. We will leverage this experience to create a fungal detection assay with unparalleled performance. Our specific aims are: 1) Finalize a 6 species Candida BSI test to detect and differentiate clinically-relevant Candida species (C. albicans, C. tropicalis, C. parapsilosis C. krusei, C. glabrata, and C. auris) based on innovative multi-melting temperature signature codes. 2) Improve sample processing to increase test blood volume and enhance assay sensitivity 3) Develop a reflex drug resistance detection assay for blood and urine samples positive for C. auris. 4) Perform analytic validation of both the primary and reflex test using Reagents on Board Automation Line (ROBAL) assembled cartridges. 5) Perform pre-clinical studies in preparation for clinical trials and eventual FDA clearance.