Invasive candidiasis in the Intensive Care unit: diagnostic stewardship, source control, and precision antifungal therapy

Abstract

INTRODUCTION: Invasive candidiasis remains one of the most challenging infections in the intensive care unit (ICU) because diagnosis is complicated by nonspecific clinical manifestations, frequent colonization, altered host immunity, complex anatomical sources and unstable pharmacokinetics. Distinguishing true invasive disease from colonization is fundamental to optimizing patient outcomes while avoiding unnecessary antifungal exposure. AREAS COVERED: This narrative review examines invasive candidiasis in critically ill adults from an ICU perspective, based on a structured PubMed/MEDLINE, Embase and Cochrane Library search of English-language literature (January 2005-May 2026). We discuss contemporary epidemiology, updated fungal nomenclature, risk factors and disease phenotypes, together with diagnostic stewardship using cultures, beta-D-glucan and molecular assays. Current evidence regarding source control, catheter management, empirical and targeted antifungal therapy, therapeutic drug monitoring, pharmacokinetic challenges during extracorporeal support, emerging agents and Candida auris is reviewed. EXPERT OPINION: The principal challenge in ICU fungal infections is not delayed antifungal therapy alone but accurate attribution of invasive disease. Positive fungal cultures or biomarkers should be interpreted within their clinical and anatomical context rather than as independent indications for treatment. Future management should integrate rapid diagnostics, host immune profiling, optimized pharmacokinetics and effective source control into phenotype-driven strategies that improve outcomes while strengthening antifungal stewards.