Angiotensin-Converting Enzyme Unit Converter

Angiotensin-converting enzyme (ACE) is an enzyme that plays a central role in regulating blood pressure. It converts the inactive peptide angiotensin I into angiotensin II, a potent vasoconstrictor that raises blood pressure. ACE also breaks down bradykinin, a substance that helps relax blood vessels.

The ACE blood test measures the level or activity of this enzyme in your serum. It is most commonly used to help diagnose and monitor sarcoidosis, a condition in which clusters of inflammatory cells (granulomas) form in various organs.

Results are typically reported in units per liter (U/L). Normal values vary by laboratory method and age, as children and adolescents naturally have ACE levels 20-50% higher than adults.

ACE is produced primarily by the vascular endothelial cells lining the blood vessels of the lungs. It is also found in smaller amounts in the kidneys, heart, brain, and other tissues. In granulomatous diseases like sarcoidosis, activated macrophages and epithelioid cells within granulomas produce additional ACE.