This test measures how much angiotensin converting enzyme (ACE) is in your blood.

Your ACE levels may be higher if you have a condition called sarcoidosis. In sarcoidosis, small abnormal knots of immune cells called granulomas form in various parts of the body. The most common place is in the lungs. These knots of cells may cause health problems. Granulomas can also form in other conditions, so you may need other tests to figure out the exact cause.

It's normal to have some ACE in your body. Certain medicines called ACE inhibitors act on ACE to control blood pressure.