Lack of correlation between serum angiotensin-converting enzyme activity and bronchoalveolar lymphocytosis in lung sarcoidosis

Abstract

Serum angiotensin-converting enzyme activity (SACE) and the number of lymphocytes in bronchoalveolar lavage fluid (BALF) are elevated in many patients with sarcoidosis, and have been proposed as monitors of disease activity. To study the relationship between these two parameters, we have compared SACE values to the percentage of BALF lymphocytes in 23 patients with pulmonary sarcoidosis. Twenty patients had recently diagnosed Stage I or II sarcoidosis and 3 were in Stage III. SACE and BALF lymphocytosis were respectively elevated in 80 and 85% of patients with Stage I and II sarcoidosis, and concordant (i.e. both elevated or both normal) in 75% of these patients. Both SACE and the percentage of BALF lymphocytes were normal in the 3 Stage III patients. No significant correlation was observed between SACE values and the percentage of BALF lymphocytes in our group of 23 patients. Discordance is liable to occur in Stage I patients where increased BALF lymphocytosis and normal SACE may be found, and in smoking patients where elevated SACE may be associated with a normal proportion of BALF lymphocytes.