Aspergillus Species

Invasive aspergillosis (IA) is a major cause of morbidity and mortality in immunosuppressed patients. This infection is caused by Aspergillus, a hyaline mold that is the etiologic agent in IA and is responsible for a variety of noninvasive or semi-invasive conditions. These syndromes range from colonization, such as a fungus ball due to Aspergillus (also known as aspergilloma); allergic responses to Aspergillus, including allergic bronchopulmonary aspergillosis; and semi-invasive or invasive infections, from chronic necrotizing pneumonia to invasive pulmonary aspergillosis and other invasive syndromes. Patients with established IA have poor outcomes; successful therapy depends not only on an early diagnosis but also on reversal of underlying immune defects. Even when therapy is begun promptly, outcomes are often poor, particularly in patients with disseminated or central nervous system disease and in those who remain profoundly immunosuppressed. New diagnostic approaches and new management strategies have been established. In this chapter clinical mycology, epidemiology, pathogenesis, clinical presentation, diagnosis, treatment, and prevention of aspergillosis are described.