[Determination of angiotensin-converting enzyme activity in internal diseases]

A convenient and reliable colorimetric method for determination of serum angiotensin-converting enzyme is worked out by modifying the method of Niels and al. Reference serum ranges of 15.45-191.2 ME/L are established in a control group of 46 healthy persons. In pulmonary sarcoidosis statistically significantly higher angiotensin-converting enzyme activity than in the healthy controls is found while in pulmonary cancer and other pulmonary diseases the angiotensin-converting enzyme activity is in the reference ranges. The importance of angiotensin-converting enzyme as a laboratory index for the early diagnosis of pulmonary sarcoidosis is discussed.