Which organism is the most common cause of candidemia in hospitalized patients?

• A. Candida albicans
• B. Candida glabrata
• C. Aspergillus fumigatus
• D. Cryptococcus neoformans

Answer: (A)

Candida albicans is the most common cause of candidemia in hospitalized patients because it is the species most often found as a colonizer of mucosal surfaces and has a strong ability to invade and disseminate when the host’s defenses are compromised. In the hospital setting, risk factors such as central venous catheters, broad-spectrum antibiotics, ICU stays, and parenteral nutrition allow Candida to enter the bloodstream, and C. albicans readily forms biofilms on devices, facilitating bloodstream infection.

While other organisms listed can cause serious fungal diseases, they have different typical presentations. Aspergillus fumigatus mainly causes invasive lung disease in severely immunocompromised individuals; Cryptococcus neoformans often presents with meningitis, especially in patients with advanced HIV infection or other severe immunosuppression. Candida glabrata can cause candidemia as well but is less common overall than C. albicans, and it may have different antifungal susceptibilities.