<unk>  is a heterogenous group of infectious diseases caused by Aspergillus (commonly A. fumigatus), a ubiquitous fungus.<unk>  may be classified according to the clinical syndrome it causes into allergic bronchopulmonary<unk> , allergic Aspergillus sinusitis, aspergilloma, chronic pulmonary<unk> , invasive<unk> , or cutaneous<unk> . Aspergillus is primarily transmitted to the human host by either inhalation of airborne conidia (usually during dust exposure during building renovation or construction) or by contaminated biomedical devices, but not from one individual to another. The pathogenesis of<unk>  varies according to the associated clinical syndrome. Allergic bronchopulmonary<unk>  and allergic Aspergillus rhinosinusitis are thought to be caused by both type I and type III hypersensitivity immune responses. On the other hand, the development of aspergilloma, chronic pulmonary<unk> , and invasive<unk>  is directly related to the growth and expansion of the Aspergillus hyphae in the lungs. Lastly, cutaneous<unk>  may result either from direct access of the Aspergillus through a skin break (primary) or dissemination of the Aspergillus to the skin from a distant infected organ (secondary). Immunocompromised status (e.g. organ or stem cell transplant recipient) and history of prior lung disease are the most important risk factors in the development of<unk> . Other risk factors include history of asthma, burn or surgical site wounds, and exposure to healthcare settings or construction sites. Following transmission, the majority of patients do not develop any clinical manifestations. The incubation of<unk>  is highly dependent on the host immune factors. The incubation period may range from a few days to years, during which the host is asymptomatic. Among immunocompetent hosts,<unk>  may result in a localized pulmonary infection, allergic bronchopulmonary<unk> , or allergic Aspergillus sinusitis. Accordingly, patients usually appear healthy but develop symptoms of asthma or sinusitis. Among immunocompromised hosts,<unk>  progresses faster and has a more invasive course, and patients are often sick-looking and lethargic. If<unk>  among immunocompromised patients is left untreated, it often progresses, and patients report worsening fever, chest pain, and hemoptysis. Specifically, invasive<unk>  eventually disseminates to non-pulmonary organs and results in life-threatening complications. PCR is the method of choice for the diagnosis of<unk> . A single negative PCR result is sufficient to rule out<unk> , whereas two positive test results are required to confirm the diagnosis. Laboratory findings consistent with the diagnosis of<unk>  include positive aspergillus antibody test, positive galactomannan test, elevated concentration of IgE immunoglobulin, and positive culture from sputum or bronchoalveolar lavage. Imaging may also be helpful, particularly in the diagnosis of aspergilloma, whereby a mobile mass (fungus ball) within a pulmonary cavity is characteristic. Treatment usually includes antifungal pharmacotherapy. Steroid administration and surgical intervention may also be indicated in some clinical syndromes. There is no vaccine against Aspergillus. Effective preventive measures include avoiding exposure to Aspergillus by personal protective equipment in dusty environments around construction sites, avoiding activities that require exposure to soil (such as yard work or gardening), and properly cleaning wounds. Prophylactic antifungal drugs is not recommended for the general population. Pharmacologic prophylaxis may be helpful in individual cases among immunocompromised patients.
Aspergillosis
Aspergilloma
Histoplasmosis
Invasive aspergillosis
Tuberculosis
Sycosis
Coccidioidomycosis
Paracoccidioidomycosis