Determination of serum angiotensin-converting enzyme in sarcoidosis.

Serum angiotensin-converting enzyme activity was measured in 72 patients with sarcoidosis and in 50 normal controls by a radiochemical assay. SACE levels were examined with respect to the 'activity' of the disease, based on clinical, radiographic and physiological assessment. SACE activity in 34 patients with clinical sarcoidosis (147 +/- 44.3 nmol/min/ml) was significantly high (p less than 0.001) when compared to that of 38 patients who had recovered from sarcoidosis (113.9 +/- 26.4 nmol/min/ml) and 50 normal subjects (97.8 +/- 21 nmol/min/ml). SACE levels were significantly different (p less than 0.01) between 15 subjects with 'active' disease (173.9 +/- 51.9 nmol/min/ml) and those with 'inactive' disease (126.1 +/- 26.3 nmol/min/ml). It is concluded that there is a strict correlation between SACE levels and 'activity' of sarcoidosis if multiple criteria (clinical, radiographic and physiological) are employed.