ANGIOTENSIN I CONVERTING ENZYME (ACE), SERUM

Angiotensin I Converting Enzyme (ACE), Serum

What it is

The Angiotensin I Converting Enzyme (ACE), Serum test measures the level of ACE in the blood. ACE is an enzyme that helps regulate blood pressure by converting angiotensin I into angiotensin II, a potent vasoconstrictor. While ACE plays an important role in cardiovascular function, serum levels are primarily used as a diagnostic marker for certain medical conditions.

Uses

This test is most commonly used to help diagnose and monitor sarcoidosis, an inflammatory disease that can affect multiple organs, especially the lungs and lymph nodes. Elevated ACE levels may also be seen in other conditions such as tuberculosis, leprosy, hyperthyroidism, and certain liver diseases. In some cases, the test is repeated over time to monitor disease activity or treatment response.

Symptoms That May Lead to the Test

Doctors may order this test if you present with persistent cough, shortness of breath, chest pain, enlarged lymph nodes, skin lesions, unexplained fatigue, or eye inflammation. These symptoms may raise suspicion of sarcoidosis or other inflammatory disorders, prompting further evaluation with ACE levels.

Abnormal Results

High ACE Levels: May suggest active sarcoidosis or other granulomatous diseases such as tuberculosis, leprosy, or histoplasmosis. Elevated levels can also occur in certain liver conditions and hyperthyroidism.

Low or Normal ACE Levels: Do not rule out sarcoidosis, as some patients may have normal enzyme activity despite the disease. ACE levels are most useful when interpreted alongside imaging, biopsy results, and other clinical findings.

Risks

The test involves a standard blood draw with minimal risks, such as slight pain, bruising, or dizziness at the puncture site. Serious complications are very rare.