Pulmonary Sarcoidosis: I. Pathophysiologic Correlations

摘要

Thirty-four patients with clinical and histologically proved sarcoidosis without other pulmonary disease were studied with chest roentgenograms, pulmonary function studies, and percutaneous needle biopsy of the lung. The conclusions drawn fell into three separate categories. The diagnostic yield of needle biopsy of the lung was very high in patients with disease of less than one year regardless of the roentgenographic findings. Ninety-five percent of the patients with disease of less than one year had diagnostic biopsies compared with a 45 per cent yield in patients with disease for longer than one year. Alveolar membrane thickening was a consistent finding on every biopsy. Total lung diffusion and arterial oxygen tension with exercise were the only function studies that showed a significant correlation with the severity of lung parenchymal change. Thus, there was statistical evidence that the functional abnormalities associated with the concept of alveolar-capillary block are related to membrane thickness. Although there were significant correlations between various function studies and roentgenographic findings with either pathologic group or diffusion, there was always a large range of values in any group. In a patient, therefore, no single function study or roentgenographic finding was a truly reliable indication of the severity of either parenchymal changes or abnormality of diffusion. The degree of impairment of vital capacity, however, proved to be a rough estimate of the diffusion level and, to a lesser extent, of the degree of pathologic change in the lung parenchyma. (Author)