aspergillosis

n.

a group of conditions caused by fungi of the genus Aspergillus, usually Aspergillus fumigatus. These conditions nearly always arise in patients with pre-existing lung disease and fall into three categories. The allergic form most commonly affects asthmatic patients and may cause collapse of segments or lobes of a lung. The colonizing form leads to formation of a fungus ball (aspergilloma), usually within a pre-existing cavity in the lung (such as an emphysematous bulla or a healed tuberculous cavity). Similar fungus balls may be found in other cavities, such as the eye or the sinuses around the nose. The third form of aspergillosis, in which the fungus spreads throughout the lungs and may even disseminate throughout the body, is rare but potentially fatal. It is usually associated with deficiency in the patient's immunity.