Diagnosis of Eosinophilic Pulmonary Diseases Chest-x-ray or computed tomography scan of the chest Demonstrating eosinophilia in peripheral blood, bronchoalveolar lavage fluid, or lung tissue Diagnosis is based on demonstration of opacities on chest imaging and identification of eosinophilia (> 450 / microL [0.45 × 10 9 / L]) in peripheral blood, bronchoalveolar lavage fluid, or lung biopsy tissue.