Echinocandin resistance due to simultaneous FKS mutation and increased cell wall chitin in a Candida albicans bloodstream isolate following brief exposure to caspofungin.

Echinocandins are first-line agents for treating severe invasive candidiasis. Glucan synthase gene (FKS1) mutations lead to echinocandin resistance but the role of enhanced chitin expression is not well recognized in clinical isolates. We report a case of bloodstream Candida albicans infection with both Fks1 hotspot mutation and elevated cell wall chitin.