ANGIOTENSIN-CONVERTING ENZYME IN SARCOIDOSIS AND OTHER PULMONARY-DISEASES - COMPARISON OF 2 METHODS OF DETERMINATION

The authors compare two methods of determining serum angiotensin-converting enzyme (ACE) in sarcoidosis and various pulmonary diseases. The Cushman-Cheung method [3], which measures hippuric acid formed from hippuryl-histidyl-leucine, appears to be more sensitive and specific than the Depierre-Roth fluorometric assay [4], which uses histidine-leucine liberated from a phenylalanine-histidine-leucine substrate. In sarcoidosis, the first method results in 59% (n = 132) high values as compared to 36% (n = 143) with the second. In other pulmonary diseases, the frequency of high values with the Cushman-Cheung method does not exceed 7%, while it reaches 30% in tuberculosis and nearly 20% in chronic obstructive lung disease with the Depierre-Roth method. The data obtained with the Cushman-Cheung method in sarcoidosis confirm previous studies. Measurement of the serum ACE level is a good test to confirm sarcoidosis; high levels are related to the extent of the disease. © 1980 Springer-Verlag.