Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2019 Jun;62(6):513-518.
doi: 10.1111/myc.12907. Epub 2019 Apr 4.

A high-throughput and rapid method for accurate identification of emerging multidrug-resistant Candida auris

Ausaf Ahmad  1 , Jonathan E Spencer  1 , Shawn R Lockhart  2 , Sabrina Singleton  2 , David J Petway  1 , Dennis A Bagarozzi Jr  1 , Owen T Herzegh  1
Affiliations

A high-throughput and rapid method for accurate identification of emerging multidrug-resistant Candida auris

Ausaf Ahmad et al. Mycoses. 2019 Jun.

Abstract

Candida auris is an emerging multidrug-resistant yeast associated with invasive infection in healthcare settings. Recently, C auris cases in the United States have been detected in 11 states with the majority of cases in New York, New Jersey and Illinois. Rapid and accurate identification of C auris is critical for patient care and the implementation of public health measures to control the spread of infection. Our aim was to develop and validate a rapid DNA extraction method using the Roche MagNA Pure 96 instrument and a TaqMan real-time PCR assay for reliable, high-throughput identification of C auris. We evaluated 247 patient dermal swab samples previously analysed by culture/MALDI-TOF. The diagnostic sensitivity and specificity were 93.6% and 97.2%, respectively. The assay was highly reproducible with a detection limit of 1 C auris CFU/10 μL. A receiver operating characteristic curve analysis of the real-time PCR data showed an area of 0.982 under the curve, with a CT cut-off value of ≤37.0. The turnaround time from DNA extraction to real-time PCR results was approximately 200 samples/day. In conclusion, we successfully validated a rapid and high-throughput method for accurate and reproducible identification of C auris with a significantly reduced turnaround time compared to culture/MALDI-TOF based methods.

Keywords: Candida auris; TaqMan real-time PCR; high-throughput rapid DNA extraction.

PubMed Disclaimer

Conflict of interest statement

CONFLIC T OF INTEREST

The authors declare that they have no conflict of interest.

Figures

FIGURE 1
FIGURE 1
Instrument response: evaluation of instrument response for real-time PCR assay. Five dilutions (from 5 × 106 to 5 × 102 CFU/mL) were prepared for evaluation of the instrument response and analytical sensitivity of real-time PCR assay. The instruments showed mean 3.30-fold (standard deviation: 0.415) increase in CT value with every 10-fold dilution
FIGURE 2
FIGURE 2
Assay sensitivity: real-time PCR assay sensitivity. Five dilutions (from 5 × 103 to 10 CFU/mL) were evaluated with twenty replicates of each dilutions. The assay was highly reproducible with a limit of detection (LOD) of 100 Candida auris CFU/mL or 1 C auris CFU/10 μL
FIGURE 3
FIGURE 3
Distribution of CT value: CT value distribution for Candida auris positive and negative samples. A centerline across the boxes indicates the median. Lower and upper boxes indicating the 25th percentile to the 75th percentile. Whiskers caps represent the maximum and minimum CT values
FIGURE 4
FIGURE 4
Receiver operating characteristic (ROC) curve: a ROC curve analysis of the real-time PCR data showed an area of 0.982 under the curve, with a CT value cut-off of ≤37.0
See this image and copyright information in PMC

References

    1. Ruiz-Gaitan A, Moret AM, Tasias-Pitarch M, et al. An outbreak due to Candida auris with prolonged colonisation and candidaemia in a tertiary care European hospital. Mycoses. 2018;61(7):498–505. - PubMed
    1. Belkin A, Gazit Z, Keller N, et al. Candida auris Infection Leading to Nosocomial Transmission, Israel, 2017. Emerg Infect Dis. 2018;24(4):801–804. - PMC - PubMed
    1. Satoh K, Makimura K, Hasumi Y, Nishiyama Y, Uchida K, Yamaguchi H. Candida auris sp. nov., a novel ascomycetous yeast isolated from the external ear canal of an inpatient in a Japanese hospital. Microbiol Immunol. 2009;53(1):41–44. - PubMed
    1. Vallabhaneni S, Kallen A, Tsay S, et al. Investigation of the first seven reported cases of Candida auris, a Globally Emerging Invasive, Multidrug-Resistant Fungus-United States, May 2013-August 2016. Am J Transplant. 2017;17(1):296–299. - PubMed
    1. CDC. Tracking Candida auris—August 2018. https://www.cdc.gov/fungal/candida-auris/tracking-c-auris.html. Accessed October 04, 2018.

Publication types

MeSH terms

LinkOut - more resources