Pulmonary manifestations of sarcoidosis.

Sarcoidosis affects the lungs in more than 90% of cases. Symptoms include cough, dyspnea, and chest pain. The entire respiratory tract can be involved. The most common areas of involvement are the airways and interstitium. Airway disease can lead to airway obstruction while interstitial lung disease can lead to restrictive disease. Patients may have a mix of these areas of involvement. For the symptomatic patient, the identification of disease involvement can usually be determined by pulmonary function testing and chest imaging. The chest X-ray staging system has been widely used in sarcoidosis, high-resolution computer tomography (HRCT) can provide detailed information regarding lung involvement. Unfortunately the various patterns seen on HRCT have limited the ability to develop a simple scoring system. Special studies such as bronchoscopy can be useful for detecting large airway disease. Other chest manifestations include adenopathy, pulmonary hypertension, and pulmonary muscle weakness. Fibrotic lung disease can lead to bronchiectasis, which can become infected.