Fungal Infections

Older adults are at increased risk of developing opportunistic fungal infections because organ transplantation, intensive cancer chemotherapy regimens, and anti-tumor necrosis factor agents are now used more commonly, and because admission to an intensive care unit, which carries many risk factors for fungal infection, has become commonplace in this group. Candida species are the most common cause of opportunistic fungal infections, and bloodstream infections are usually treated with fluconazole or an echinocandin antifungal agent. Invasive mold infections are mostly caused by Aspergillus species; in older adults, they cause primarily pulmonary and sinus infections, and they are associated with a high mortality rate. The endemic fungi, Histoplasma capsulatum, Coccidioides species, and Blastomyces dermatitidis, cause infection when the mold form is dispersed and inhaled from the environment in those specific areas of the country in which these organisms flourish. Amphotericin B is used for initial treatment of severe histoplasmosis, coccidioi­domycosis, and blastomycosis; itraconazole is the therapy of choice for most mild to moderate infections due to these endemic mycoses.