Interstitial lung disease is characterized by which of the following symptoms?

Interstitial lung disease (ILD) is primarily characterized by progressive dyspnea on exertion and a nonproductive cough. The disease affects the interstitium of the lungs, leading to inflammation and fibrosis, which consequently impairs lung function.

In patients with ILD, the hallmark symptom is dyspnea, which often starts with exertion and gradually worsens over time. The nonproductive cough is also common as the fibrotic process does not usually lead to mucus production, as seen in conditions like chronic bronchitis. Patients may describe a gradual struggle to breathe, particularly during activities that require increased exertion.

The other options, such as a productive cough with hemoptysis, rapidly worsening respiratory distress, and persistent wheezing and chest tightness, typically align more with other pulmonary conditions. For example, a productive cough with hemoptysis can indicate infections, certain cancers, or bronchiectasis, while wheezing and chest tightness often point to obstructive diseases like asthma or COPD rather than ILD. Similarly, rapidly worsening respiratory distress might suggest acute respiratory conditions rather than the progressive nature usually seen in ILD.