American Board of Internal Medicine (ABIM) Certification Practice Exam

What are the typical symptoms of acute hypersensitivity pneumonitis presented within 48 hours of high-level exposure?

1. Chest pain and fever

2. Cough and shortness of breath

3. Dizziness and headaches

4. Nausea and fatigue

The correct answer is: Cough and shortness of breath

Acute hypersensitivity pneumonitis, often referred to as extrinsic allergic alveolitis, is an immunologically mediated inflammatory response in the lungs that occurs following exposure to organic antigens. When individuals experience high-level exposure to these antigens, the manifestations typically occur within a short time frame, usually within 48 hours. The hallmark symptoms of acute hypersensitivity pneumonitis include cough and shortness of breath. These symptoms arise due to inflammation in the airways and lung parenchyma, leading to obstruction and impaired gas exchange. Cough is a common reflex response to lung irritation and injury, serving as a protective mechanism to clear the airways. Shortness of breath indicates a more significant impact on lung function, as inflammation can lead to decreased oxygen transfer. Understanding these symptoms is critical for timely diagnosis and management. While chest pain and fever may occur in some respiratory conditions, they are not specifically indicative of hypersensitivity pneumonitis. Other options like dizziness, headaches, nausea, and fatigue, while they might surface in various respiratory or systemic reactions, do not represent the classic presenting symptoms associated with this lung condition triggered by inhaling organic dust, molds, or other allergens.