Pulmonary Function in Diffuse Sarcoidosis

Respiratory function was studied in 44 cases of sarcoidosis. Patients were classified into several groups depending on radiological findings. There was little correlation between functional abnormality and radiological change until advanced parenchymal infiltration occurred. The most common findings were lowered forced vital capacity, total lung capacity, diffusing capacity, and dynamic compliance. Significant correlations were found between diffusing capacity and forced vital capacity, diffusing capacity and total lung capacity, and between arterial oxygen tension and forced expiratory volume in 1 sec. There were no significant correlations between diffusing capacity and arterial oxygen tension or between diffusing capacity and dynamic compliance. Evidence of diffuse expiratory airway obstruction in 13 sarcoid patients who did not smoke is assumed to be due to peri-bronchiolar peripheral airway involvement