Etest ECVs/ECOFFs for detection of resistance in prevalent and three non-prevalent Candida spp. to triazoles and amphotericin B and Aspergillus spp. to caspofungin: Further assessment of modal variability

A Espinel-Ingroff (1) , M Sasso (2) , J Turnidge (3) , Mc Arendrup (4) , F Botterel (5) , N Bourgeois (2) , B Bouteille (6) , E Canton , S Cassaing (7) , E Dannaoui (8) , M Dehais (9) , L Delhaes (10) , D Dupont (11) , A Fekkar (12) , J Fuller (13) , G Garcia-Effron (14) , J Garcia (15) , G M Gonzalez (16) , N P Govender (17) , H Guegan (18) , J Guinea (19) , S Houzé (20) , C Lass-Flörl (21) , T Pelaez (22) , A Forastiero , M Lackner (21) , R Magobo (17)

1 VCU - Virginia Commonwealth University
2 Hôpital Lapeyronie [CHU Montpellier]
3 University of Adelaide
4 Statens Serum Institut [Copenhagen]
5 CHU Henri Mondor [Créteil]
6 CHU Limoges
7 CHU Toulouse - Centre Hospitalier Universitaire de Toulouse
8 Unité de Parasitologie-Mycologie [CHU HEGP]
9 ESCAPE - Epidémiosurveillance de protozooses à transmission alimentaire et vectorielle
10 CHU Bordeaux - Centre Hospitalier Universitaire de Bordeaux
11 HCL - Hospices Civils de Lyon
12 CHU Pitié-Salpêtrière [AP-HP]
13 UWO - University of Western Ontario
14 UNL - Universidad Nacional del Litoral [Santa Fe]
15 Hospital Universitario La Paz-Carlos III [Madrid]
16 UANL - Universidad Autonoma de Nuevo Leon [Mexique]
17 NICD - National Institute for Communicable Diseases [Johannesburg]
18 Irset - Institut de recherche en santé, environnement et travail
19 Hospital General Universitario "Gregorio Marañón" [Madrid]
20 MERIT - UMR_D 261 - Mère et enfant en milieu tropical : pathogènes, système de santé et transition épidémiologique
21 Leopold Franzens Universität Innsbruck - University of Innsbruck
22 Universidad de Oviedo = University of Oviedo

Susceptibility testing is an important tool in the clinical setting; its utility is based on the availability of categorical endpoints, breakpoints (BPs) or epidemiological cutoff values (ECVs/ECOFFs). CLSI and EUCAST have developed antifungal susceptibility testing, BPs and ECVs for some fungal species. Although the Concentration Gradient Strip BioMerieux Etest is useful for routine testing in the clinical laboratory, ECVs are not available for all agent/species; the lack of clinical data precludes development of BPs. We re-evaluated and consolidated Etest data points from three previous studies, and included new data. We defined ECOFFinder Etest ECVs for three sets of species/agent combinations: fluconazole, posaconazole and voriconazole and 8 Candida spp.; amphotericin B and 3 non-prevalent Candida spp.; and caspofungin and 5 Aspergillus spp. The total of Etest MICs from 23 laboratories (Europe, the Americas, South Africa) included (antifungal agent/dependent): 17,242 Candida albicans, 244 C. dubliniensis, 5,129 C. glabrata species complex (SC), 275 C. guilliermondii (Meyerozyma guilliermondii), 1,133 C. krusei (Pichia kudriavzevii), 933 C. kefyr (Kluyveromyces marxianus), 519 C. lusitaniae (Clavispora lusitaniae), 2,947 C. parapsilosis SC, 2,214 C. tropicalis, 3,212 Aspergillus fumigatus, 232 A. flavus, 181 A. niger, and 267 A. terreus SC isolates. Triazole MICs for 66 confirmed non-wild-type (non-WT) Candida isolates were available (ERG11 point mutations). Distributions fulfilling CLSI ECV criteria were pooled and ECOFFinder Etest ECVs were established for triazoles (9 Candida spp.); amphotericin B (3 less-prevalent Candida spp.) and caspofungin (4 Aspergillus spp.). Etest fluconazole ECVs could be good detectors of Candida non-WT isolates (59/61 Non-WT: 4 of 6 species).

Mots clés: Aspergillus spp.; Candida; ECOFFS; ECVs; ERG11 mutants; amphotericin B; antifungal resistance; caspofungin; nonprevalent Candida; triazoles

Domaines: Sciences du Vivant [q-bio]

A Espinel-Ingroff, M Sasso, J Turnidge, Mc Arendrup, F Botterel, et al.. Etest ECVs/ECOFFs for detection of resistance in prevalent and three non-prevalent Candida spp. to triazoles and amphotericin B and Aspergillus spp. to caspofungin: Further assessment of modal variability. Antimicrobial Agents and Chemotherapy, 2021, 65 (11), pp.AAC0109321. ⟨10.1128/AAC.01093-21⟩. ⟨hal-03355996⟩