Which pulmonary manifestation is a recognized complication of rheumatoid arthritis?

• A. Pneumothorax
• B. Interstitial lung disease
• C. Pulmonary edema
• D. Pneumonia

Answer: (B)

Rheumatoid arthritis can involve the lungs directly, and the most recognized pulmonary complication is interstitial lung disease. This option reflects the chronic inflammatory and fibrotic processes that RA can trigger in the lung interstitium, especially in patients with longstanding, seropositive disease. Clinically, patients often present with a slowly progressive cough and dyspnea on exertion. Spirometry typically shows a restrictive pattern with reduced lung volumes, and diffusion capacity for carbon monoxide (DLCO) is often decreased, indicating impaired gas exchange. Imaging commonly reveals bilateral interstitial changes, usually in the lower lungs with subpleural involvement; patterns can include usual interstitial pneumonia or nonspecific interstitial pneumonia, reflecting the fibrotic remodeling of lung tissue.

The other choices describe conditions that are not specific RA pulmonary manifestations. Pneumothorax isn’t a characteristic RA lung complication, though it can occur for various reasons. Pulmonary edema points to left-sided heart failure or fluid overload rather than a primary RA-related process. Pneumonia is an infectious process; RA patients may be at higher infection risk due to disease or therapy, but it is not a direct, recognized RA-specific pulmonary complication.