Pulmonary sarcoidosis: correlation of serum angiotensin-converting enzyme with blood and bronchoalveolar lymphocytes.

Blood and bronchoalveolar (BA) cell populations were compared with serum angiotensin-converting enzyme activity (SACE) in 22 smoking and nonsmoking patients with recently diagnosed or active sarcoidosis. There was no correlation between SACE and blood lymphocyte populations, but a significant correlation was found between the number of BA lymphocytes and SACE and the number of BA T cells and SACE. In no case was SACE elevated when the number of BA lymphocytes was normal, but in 10 patients with increased numbers of BA lymphocytes SACE was normal. In fact, SACE was increased in less than one-third (7/22) of the patients. These results suggest that both SACE and the number of lymphocytes in lavage fluid reflect the intensity of the lung's inflammatory response in sarcoidosis but that quantification of BA lymphocytes is a more sensitive measure than SACE of active pulmonary sarcoidosis.