Hypersensitivity pneumonitis is an immunologically mediated form of lung disease, resulting from inhalation exposure to a large variety of antigens. For unknown reasons, a subgroup of patients with HP without a known inciting antigen exposure develops chronic disease with progressive pulmonary fibrosis (the leading cause of death). Accurately identifying patients at risk of disease progression is necessary for prognosis and therapy.~Enrolled subjects will be followed for 24 months and complete 5 visits to one of the study centers. Blood biomarkers will be collected in addition to other clinical data to determine if these biomarkers can predict disease progression.
Up to 135 patients with hypersensitivity pneumonitis will be enrolled at 7 clinical centers across the United States. Patients will be followed for 24 months to determine if biomarkers in the blood can predict disease progression.