Elevated Serum Angiotensin I Converting Enzyme in Sarcoidosis

Serum angiotensin I converting enzyme was found to be elevated in 56 patients with sarcoidosis (52.7 +/- 25.4 nmole per min per ml) compared to 84 normal control subjects (28.2 +/- 11.3 nmole per min per ml), 22 patients with tuberculosis (26.4 +/- 10.9 nmole per min per ml), and 20 patients with lymphomas (31.8 +/ 13.9 nmole per min per ml). Forty-eight per cent of the patients with sarcoidosis had values of enzymatic activity that were higher than 2 SD above the mean value of the control population; the false-positive rate in all nonsarcoidosis subjects combined was 5.5 per cent. Patients with parenchymal disease with or without hilar adenopathy had values somewhat higher than those with hilar adenopathy alone, but the difference was not significant (P less than 0.1). Patients with a known duration of disease greater than 2 years also had somewhat higher values than those with known disease less than 2 years, but the difference was not significant (P less than 0.1). There was no significant difference in values for patients receiving or not receiving steroids.