Invasive Candidiasis in Critically Ill Patients: Fundamental Concepts and Future Directions.

TOPIC

IMPORTANCE

Invasive candidiasis (IC) is a common complication in patients in ICUs. IC can be divided into bloodstream infections (candidemia) and deep-seated infections. Candida infections are associated with high mortality and longer hospital stays. Moreover, the emergence of Candida auris and other species prone to cause ICU outbreaks highlights the importance of this pathogen.

REVIEW FINDINGS: Candidemia represents about 20% of bloodstream infections in ICU patients, whereas intraabdominal candidiasis, the most common form of deep-seated infection, predominantly affects surgical ICU patients. Regarding species distribution, Candida albicans is the most common species; however, non-albicans species have become more prevalent in the past decade. Clinical signs of IC are indistinguishable from bacterial infections; therefore, identifying patients at risk of IC is key to choosing the right diagnostic approach. Diagnostic tests include conventional methods such as blood and tissue cultures; however, they have suboptimal sensitivity and are time-dependent, which delay the confirmation of IC. As a result, newer molecular tests offer faster results; however, their use remains limited by cost and lack of external validation. Once IC is diagnosed, first-line treatment is with echinocandin antifungals, with the option of switching to azoles in selected patients. In addition, new antifungals are being tested to treat multidrug-resistant Candida species.

SUMMARY: Our results show that Candida species is a significant pathogen in ICU patients and has a heterogeneous clinical presentation. Conventional diagnostic methods lack sufficient sensitivity to detect IC at an early stage. New diagnostic strategies may support timely antifungal therapy.