Lab Matters Summer 2024 | Page 15

INDUSTRY MATTERS

Figure 2 . Sensitivity confirmation for the EURORealTime C . auris ECH-R workflow ( total ~ 3 hours ). NC : negative control , PC : positive control

In silico analysis predicted all five clades of C . auris ( 42 ) genome ( as of May 8 , 2023 ) to be detectable by both PCR assays , with exception of 10 strains identified in Lebanon in 2021 . 7 For the resistance assay , 2,834 additional C . auris strains ( as of Nov . 17.2023 ), of which 88 contain echinocandinsresistance-markers ( 22xS369F , 19xS639Y , 47xS639P ), showed 100 % match to the FKS-specific or respective mutationspecific oligonucleotide sequences .

Cross-reactivity was not identified among non-C . auris microorganisms for ITS and FKS oligonucleotides . A wet-lab study confirmed no cross-reactivity observed among C . albicans , C . duobushaemulonii , C . glabrata , C . haemulonii , C . krusei , C . lusitaniae , Kodameae ohmeri and Saccharomyces cerevisiae . Plasmids ( 10 7 copies / reaction ) carrying the FKS gene encoding S639 ( 1xTCT- and 1xTCC-codon , wild-type ) and S639T showed no relevant cross-reactivity with the mutation-specific probes .

In summary , both PCR assays together with the automated chemagic TM 360 extraction system provide high sensitivity and scalable solution for choice of either rapid C . auris screening or together with echinocandins resistance detection . g

Revvity is an APHL Platinum Level Sustaining Member .

References :

1 . Lima A , Widen R , Vestal G , Uy D , Silbert S . A TaqMan Probe-Based Real-Time PCR Assay for the Rapid Identification of the Emerging Multidrug-Resistant Pathogen Candida auris on the BD Max System . J Clin Microbiol . 2019 Jun 25 ; 57 ( 7 ): e01604-18 . doi : 10.1128 / JCM . 01604-18 . PMID : 31068411 ; PMCID : PMC6595442 .

2 . Chowdhary A , Prakash A , Sharma C , Kordalewska M , Kumar A , Sarma S , Tarai B , Singh A , Upadhyaya G , Upadhyay S , Yadav P , Singh PK , Khillan V , Sachdeva N , Perlin DS , Meis JF . A multicentre study of antifungal susceptibility patterns among 350 Candida auris isolates ( 2009-17 ) in India : role of the ERG11 and FKS1 genes in azole and echinocandin resistance . J Antimicrob Chemother . 2018 Apr 1 ; 73 ( 4 ): 891-899 . doi : 10.1093 / jac / dkx480 . PMID : 29325167 .

3 . Rhodes J , Abdolrasouli A , Farrer RA , Cuomo CA , Aanensen DM , Armstrong-James D , Fisher MC , Schelenz S . Genomic epidemiology of the UK outbreak of the emerging human fungal pathogen Candida auris . Emerg Microbes Infect . 2018 Mar 29 ; 7 ( 1 ): 43 . doi : 10.1038 / s41426-018-0045-x . Erratum in : Emerg Microbes Infect . 2018 May 31 ; 7 ( 1 ): 104 . PMID : 29593275 ; PMCID : PMC5874254 .

4 . Berkow EL , Lockhart SR . Activity of CD101 , a long-acting echinocandin , against clinical isolates of Candida auris . Diagn Microbiol Infect Dis . 2018 Mar ; 90 ( 3 ): 196-197 . doi : 10.1016 / j . diagmicrobio . 2017.10.021 . Epub 2017 Nov 7 . PMID : 29307565 .

5 . NIH National Library of Medicine Nucleotide BLAST : https :// blast . ncbi . nlm . nih . gov / Blast . cgi ? CMD = Web & PAGETYPE = BLASTHome . Accessed on 06 March 2024 . 6 . Pathogenwatch – A Global Platform for Genomic Surveillance database : https :// pathogen . watch /. Accessed on 06 March 2024 .

7 . Reslan L , Araj GF , Finianos M , El Asmar R , Hrabak J , Dbaibo G , Bitar I . Molecular Characterization of Candida auris Isolates at a Major Tertiary Care Center in Lebanon . Front Microbiol . 2022 Jan 25 ; 12:770635 . doi : 10.3389 / fmicb . 2021.770635 . PMID : 35145489 ; PMCID : PMC8822126 .