Development and Validation of a Real-Time PCR Assay for Rapid Detection of Candida auris from Surveillance Samples

Abstract

<i>Candida auris</i> is an emerging multidrug-resistant yeast causing invasive health care-associated infection with high mortality worldwide. Rapid identification of <i>C. auris</i> is of primary importance for the implementation of public health measures to control the spread of infection. To achieve these goals, we developed and validated a TaqMan-based real-time PCR assay targeting the internal transcribed spacer 2 (<i>ITS</i>2) region of the ribosomal gene. The assay was highly specific, reproducible, and sensitive, with the detection limit of 1 <i>C. auris</i> CFU/PCR. The performance of the <i>C. auris</i> real-time PCR assay was evaluated by using 623 surveillance samples, including 365 patient swabs and 258 environmental sponges. Real-time PCR yielded positive results from 49 swab and 58 sponge samples, with 89% and 100% clinical sensitivity with regard to their respective culture-positive results. The real-time PCR also detected <i>C. auris</i> DNA from 1% and 12% of swab and sponge samples with culture-negative results, indicating the presence of dead or culture-impaired <i>C. auris</i> The real-time PCR yielded results within 4 h of sample processing, compared to 4 to 14 days for culture, reducing turnaround time significantly. The new real-time PCR assay allows for accurate and rapid screening of <i>C. auris</i> and can increase effective control and prevention of this emerging multidrug-resistant fungal pathogen in health care facilities.