Upon completion of the chapter, the reader will be able to:
Differentiate epidemiologic differences and host risk factors for acquisition of primary and opportunistic invasive fungal diseases.
Recommend appropriate empiric or targeted antifungal therapy for the treatment of invasive fungal diseases.
Describe the components of a monitoring plan to assess effectiveness and adverse effects of pharmacotherapy for invasive fungal infections.
Evaluate the role of antifungal prophylaxis in the prevention of opportunistic fungal diseases.
Invasive fungal infections or invasive mycoses are general terms for diseases caused by the invasion of living tissue by fungi. In contrast to superficial mycoses (see Chapter 85), invasive fungal infections are less common but are of greater medical concern because of their disproportionately higher severity and mortality. Approximately 1.5 million people die each year from the 10 most common invasive fungal infections, which is higher than World Health Organization mortality estimates for tuberculosis (1.4 million) or malaria (1.2 million).1 However, these numbers likely underestimate the actual mortality burden of invasive fungal infections considering that the four most common infections (cryptococcosis, invasive candidiasis, invasive aspergillosis [IA], and Pneumocystis jiroveci pneumonia) are often underdiagnosed and not reportable diseases to public health agencies (Table 86–1).
Table 86–1Invasive Mycoses ||Download (.pdf) Table 86–1 Invasive Mycoses
|Primary (Endemic) Invasive Fungi |
|Histoplasma capsulatuma |
|Coccidioides immitis/Coccidioides posadasiia |
|Blastomyces dermatitidisa |
|Opportunistic Invasive Fungi |
| Candida species (C. albicans, C. glabrata, C. parapsilosis, C. tropicalis, C. krusei, and others)a |
| Cryptococcus neoformansa |
| Trichosporon spp. and others |
|Hyalohyphomycoses (non-dematiaceous) |
| Aspergillus fumigatus, Aspergillus terreus, Aspergillus flavus, and other speciesa |
| Fusarium solani and Fusarium oxysporum |
| Mucorales (formally zygomycosis) (Mucor, Absidia, Rhizopus, Cunninghamella, and Rhizomucor) |
| Penicillium species |
|Phaeohyphomycoses (dematiaceous) |
| Pseudallescheria boydii (Scedosporium spp.) |
| Bipolaris |
| Alternaria |
| Exserohilum rostratum |
| Pneumocystis jiroveci (formerly P. carinii)a |
Invasive fungal diseases are broadly categorized as either primary or opportunistic mycoses. Primary invasive fungal diseases develop following exposure to fungal spores or conidia in the soil that, when disturbed, can become aerosolized and inhaled leading to infection, even in an immunocompetent patient exposed to a sufficient inoculum. Because these fungi are in specific soil types in select geographic areas, they are also referred to as endemic fungi. In the United States, three species (Histoplasma capsulatum, Blastomyces dermatitidis, and Coccidioides immitis/Coccidioides posadasii) account for most of these infections (see Table 86–1).
In contrast, opportunistic fungal diseases are most frequently encountered in the setting of compromised host immune defenses and are caused by a wider spectrum of less virulent fungal species that rarely cause infection in healthy patients (see Table 86–1). Hence, the spectrum, severity, and outcome of ...