Aspergillus fumigatus is a causative agent of Hypersensitivity pneumonitis, Invasive lung disease and Allergic bronchopulmonary disease. Elevated levels of IgG antibodies to Aspergillus are consistent with the diagnosis of Aspergillosis. These antibodies may persist even after a successful therapy. This test is used for the diagnosis of Aspergillus infections; monitoring disease progression and treatment response; risk assessment In individuals at high risk of Aspergillus infections, such as lung transplant recipients or patients with chronic obstructive pulmonary disease (COPD). It is used as an adjunct in the diagnosis of acute Aspergillus infections or for screening high-risk populations.