Histoplasmosis | Inhalation of airborne mold spores | H. capsulatum—most common source of respiratory infection. Inhabits soil contaminated by bird and bat droppings. Highly concentrated in the Ohio and Mississippi Valley regions of the United States and also in Eastern Canada, Mexico, Central America, and South America. Coexists with the H. duboisii variety (which does not cause pulmonary infection) in Central and Western sub-Saharan regions | Patients with preexisting COPD Immune-deficient hosts, e.g., patients infected with AIDS Elderly patients | Diagnostic procedure to differentiate malignancy from histoplasmoma Pulmonary resection of infected cavitary lesions with or without antifungal therapya Surgical removal of broncholiths by open resection, minimally invasive VATS, or bronchoplastic proceduresb |
Coccidioidomycosis | Inhalation of airborne mold spores | Coccidioides immitis—causes lung infection in more than 60% of cases. Soil dwelling fungus native to the San Joaquin Valley region of California. The Coccidioides posadasii variant is endemic to certain arid-to-semi-arid areas of the southwestern United States, northern portions of Mexico, and scattered areas in Central America and South America | Immune-deficient hosts Elderly patients | Diagnostic evaluation of pulmonary nodules, symptomatic nonresponsive cavitary disease, and complications of infection, including effusion, pneumothorax, and empyemab |
Blastomycosis | Inhalation of airborne mold spores | Blastomyces dermatitidis found in midwest and northern United States, as well as Canada. Produces symptoms similar to Histoplasmosis | | |
Paracoccidioidomycosis | Inhalation of airborne mold spores | P. brasiliensis found in Latin America with highest concentration in Brazil, Argentina, Colombia, and Venezuela. Infects primarily agricultural workers. Chronic disease associated with fever and bilateral lung infiltrates leading to fibrotic lung disease. | | Surgery to rule out carcinoma on rare occasions. Surgery to manage persistent consolidation caused by airway impingementb Reconstructive surgery occasionally warranted to alleviate sequelae of fibrotic disease |
Penicillosis | Inhalation of airborne mold spores | Penicillium marneffei found primarily in tropical Asia | |
Spirotrochosis | Cutaneous contact with organism | Sporothrix schenckii is found in tropical and temperate zones worldwide, but unlike other endemic mycoses, the infection occurs by a cutaneous route through contact with the organism in the soil and in moss | Patients with preexisting COPD Immune-deficient hosts with HIV and low CD4 counts more commonly affected than other immune-suppressed individuals Culture results return rapidly; serology is helpful for diagnosis | |
Zygomycosisb | Inhalation of airborne mold spores | Zygomycetes (i.e., Rhizopus, mucormycosis, Cunninghamella and others) are molds found in decaying vegetation and soil worldwide | Diabetes, hematologic malignancy with transplantation, solid organ transplantation, treatment of iron overload states, AIDS, and immune-compromised patients using voraconazole or posaconazole, a new class of drugs with broad antifungal activity | Angioinvasive fungi cause rapid necrosis leading to extensive destruction and death Treatment requires urgent pulmonary resection with removal of all devitalized tissue, up to and including pneumonectomyb |
Hyalohyphomycosis | Inhalation of airborne mold spores | Hyalohyphomycoses (i.e., Fusarium, Scedosporium) are dematiaceous (black) molds responsible for an increase of pneumonia in transplant recipients and in patients with hematologic malignancies. Caused by inhalation of mold spores. Appearance is similar to Aspergillus on histologic examination. Differentiation relies on culture speciation. Have unique ability to sporulate in vivo leading to vascular invasion with yeast dissemination | | Dematiaceous molds produce abscesses and infected cavities difficult to eradicate with antimicrobials alone Surgical excision for localized disease may be indicated given poor response of organism to antifungal therapy |
Phaeohyphomycosis | Inhalation of airborne spores or inoculation of black molds | Phaeohyphomycosis (i.e., Curvularia, Bipolaris, Exophiala, and Alternaria) is caused by inhalation or inoculation of species of black molds leading to allergic bronchopulmonary disease (ABPD) associated with eosinophil elevations | Non-allergic pulmonary disease occurs in immunocompromised individuals and represents tissue invasion of this fungus which is a common airway colonizer Invasive phaeohyphomycosis may manifest as pneumonias or parenchymal or endobronchial nodules | May cause severe, life-threatening infections in immune-deficient, as well as immune-competent hosts |
Trichosporon | Trichosporon and adiaspiromycosis caused by Emmonsia crescens cause significant fulminant, often fatal disease |
OPPORTUNISTIC FUNGAL INFECTIONS | TRANSMISSION | INFECTING ORGANISM | AT-RISK POPULATIONS | ROLE OF SURGICAL TREATMENT |
Candidiasis | Endogenous exposure | Most common infecting organism in ICU. Majority of infections arise in patients with vascular access devices Candida nonalbicans associated with higher mortality and rising more rapidly than Candida albicans | Transplant recipients. Most common infection of SOT (SOT and HSOT) Cancer patients (hematologic malignancies and chemotherapy induced immune-suppression) Long-term immunosuppression with steroids, Sirolimus, lympholytic treatment; or Infliximab Patients with other debilitating disease (Lupus, Crohn's) | |
Aspergillosis | Ubiquitous molds found in organic matter. Endogenous exposure is primary mode of severe life-threatening illness | The majority of illness is caused by Aspergillus fumigatus and Aspergillus niger and, less frequently, Aspergillus flavus and Aspergillus clavatus. The aspergillosis species causes 4 main syndromes: | Patients with chronic neutropenia Nonneutropenic patients who are immune deficient secondary to steroid use Solid organ transplant recipients with chronic pulmonary damage | |
| | allergic bronchopulmonary aspergillosis (ABPA) localized chronic necrotizing Aspergillus pneumonia (chronic necrotizing pulmonary aspergillosis [CNPA]), invasive aspergillosis (IPA) | Invasive aspergillosis is the most common organism in HSOT recipients. Cystic fibrosis Organisms proliferate in a preexisting cavity in an immune-competent host Organisms invade the vasculature in immune-deficient host | |
Emerging fungal infections (see above) |
Cryptococcus | Although widely disseminated in nature, endogenous exposure is primary mode of severe life-threatening infection | Infection with Cryptococcus neoformans may lead to neurologic sequelae | HIV Transplant recipients | |
Pneumocystis jirovecii d(previously Pneumocystis carinii) | Airborn innoculation | Pneumocystosis jirovecii | HIV Immunosuppressed individuals | Diagnosis of organism |