In vivo evolution to echinocandin resistance and increasing clonal heterogeneity in Candida auris during a difficult-to-control hospital outbreak, Italy, 2019 to 2022
Giulia Codda, Edward Willison, Laura Magnasco, Paola Morici, Daniele Roberto Giacobbe, Antonella Mencacci, Daniele Marini, Małgorzata Mikulska, Matteo Bassetti, Anna Marchese, Vincenzo Di Pilato
Abstract
A difficult-to-control outbreak of Candida auris is ongoing in a large tertiary care hospital in Liguria, Italy, where it first emerged in 2019. In a retrospective analysis, 503 cases of C. auris carriage or infection were observed between July 2019 and December 2022. Genomic surveillance identified putative cases that no longer occurred as part of one defined outbreak and the emergence of echinocandin (pandrug) resistance following independent selection of FKS1 S639F and FKS1 F635Y mutants upon prolonged exposure to caspofungin and/or anidulafungin.