ANCA antineutrophil cytoplasmic autoantibodies BAL bronchoalveolar lavage CT computed tomography D LCO diffusing capacity of the lung for carbon monoxide FVC forced vital capacity GM-CSF granulocyte–macrophage colony stimulating factor HRCT high-resolution CT ILD interstitial lung disease MRI magnetic resonance imaging PAS periodic acid–Schiff PFT pulmonary function test/ing PH pulmonary hypertension List of abbreviations