Inclusion Criteria:  Diagnosis of chronic hypersensitivity pneumonitis for at least 3 to 6 months. Age 18 through 80 years. Diagnosis of chronic hypersensitivity pneumonitis by HRCT Able to understand and sign a written informed consent form. Able to understand the importance of adherence to the study protocol and willing to follow all study requirements  Exclusion Criteria:  Not a suitable candidate for enrollment or unlikely to comply with the requirements of this study Known explanation for the interstitial lung disease Clinical diagnosis of any connective tissue disease Listed or expected to receive a lung transplant within 4 months from enrollment Pregnant women