They usually present with acute dyspnea, fever and cough, which rapidly develops into respiratory failure. Steroid therapy is effective.
Some cases spontaneously remit.
Peripheral eosinophilia cell is present at the onset of the disease. The cause of this disease is unknown. A hypersensitivity reaction to an unknown allergen is postulated. The plain chest radiograph reveals acute progression of diffuse opacities involving both lungs. Kerley's lines and pleural effusions are frequently present.