Pulmonary function in sarcoidosis.

Pulmonary function testing provides an important insight into the pathophysiology in patients with sarcoidosis. Major functional abnormalities in this disease include decreased diffusing capacity, lung compliance and lung volumes. Arterial oxygen desaturation with exercise is common. Airways obstruction may occur as an isolated finding or be superimposed on the interstitial process. The activity of the disease cannot be well determined by pulmonary function tests but serials testing is helpful in detecting progression or improvement.