Angiotensin Converting Enzyme (ACE)

The Angiotensin Converting Enzyme (ACE) test contains 1 test with 1 biomarker.

Brief Description: The Angiotensin Converting Enzyme (ACE) test is a specialized laboratory assay designed to measure the level of ACE—an enzyme primarily found in the lungs and blood vessels—in the blood. ACE plays a critical role in regulating blood pressure and fluid balance.

Also Known As: ACE Test, SACE Test, Serum Angiotensin Converting Enzyme Test, Serum ACE test

Collection Method: Blood Draw

Specimen Type: Serum

Test Preparation: No preparation required

When is an Angiotensin Converting Enzyme test ordered?

When a person exhibits indications or symptoms that suggest sarcoidosis, such as:

• Granulomas
• a persistent cough or breathing difficulties
• Red, tearing eyes
• aching joints

This is especially true if the patient is between the ages of 20 and 40, which is the age range at which sarcoidosis is most common.

When a patient has been diagnosed with sarcoidosis and their initial ACE levels were high, a medical professional may request ACE testing on a frequent basis to track how the patient's ACE levels vary over time as a sign of the disease's progression.

What does an Angiotensin Converting Enzyme blood test check for?

The enzyme angiotensin-converting enzyme aids in controlling blood pressure. Sarcoidosis, a systemic condition with no known cause that frequently affects the lungs but may also affect the eyes, skin, nerves, liver, and heart, can occasionally be identified by an elevated blood level of ACE. The ACE level in the blood is determined by this test.

Granulomas, which are small tumor-like masses of immunological and inflammatory cells and fibrous tissue that form nodules under the skin and in organs all over the body, are a characteristic symptom of sarcoidosis. When granulomas are present in large enough numbers, they alter the structure of the tissues around them, which can lead to injury, inflammation, and disruption of normal processes. The granuloma's outer border cells have a higher ACE production capacity. When granulomas associated with sarcoidosis appear, the blood's concentration of ACE may rise.

Lab tests often ordered with an Angiotensin Converting Enzyme test:

When an ACE test is ordered, it's typically part of a broader evaluation of sarcoidosis and related conditions. Here are some tests commonly ordered alongside it:

1. Complete Blood Count (CBC) with Differential:

   • Purpose: To evaluate overall blood health.
   • Why Is It Ordered: To check for anemia or other blood cell abnormalities, which can accompany sarcoidosis or other systemic diseases.

2. Liver Function Test:

   • Purpose: To assess liver health.
   • Why Is It Ordered: To evaluate liver function, as sarcoidosis can also affect the liver.

3. Serum Calcium:

   • Purpose: To measure the level of calcium in the blood.
   • Why Is It Ordered: To check for hypercalcemia, which can occur in sarcoidosis due to increased Vitamin D production by granulomas.

4. 25-Hydroxy Vitamin D Test:

   • Purpose: To measure the level of Vitamin D in the blood.
   • Why Is It Ordered: To evaluate Vitamin D status, which can be altered in sarcoidosis.

5. Erythrocyte Sedimentation Rate (ESR) and C-Reactive Protein (CRP):

   • Purpose: To measure markers of inflammation in the body.
   • Why Is It Ordered: To assess systemic inflammation, which can be indicative of active sarcoidosis or other inflammatory conditions.

These tests, when ordered alongside an ACE test, provide a comprehensive evaluation of a patient suspected of having sarcoidosis. They help to confirm the diagnosis, assess the extent and activity of the disease, monitor response to treatment, and detect complications. The specific combination of tests will depend on the individual’s symptoms, clinical presentation, and the organs involved.

Conditions where an Angiotensin Converting Enzyme test is recommended:

The Angiotensin Converting Enzyme test is particularly relevant for diagnosing and monitoring conditions such as:

1. Sarcoidosis: Elevated ACE levels are often associated with sarcoidosis due to increased ACE production by inflammatory cells in granulomas.

How does my health care provider use an Angiotensin Converting Enzyme test?

Angiotensin-converting enzyme testing is typically requested to identify and track sarcoidosis. It is frequently requested as part of an inquiry into the origin of a collection of unsettling chronic symptoms that may be brought on by sarcoidosis.

A condition known as sarcoidosis causes tiny nodules, or granulomas, to develop in the body's organs and beneath the skin. When sarcoidosis is present, the cells that surround granulomas have the capacity to create more ACE, and the blood level of ACE may also rise.

With disease activity, the blood level of ACE frequently increases and decreases. If ACE is initially increased in a sarcoidosis patient, the ACE test can be used to track the progression of the condition and gauge how well corticosteroid therapy is working.

A doctor may request ACE in addition to other tests, such as fungal testing or AFB tests to look for mycobacterial infections. This might make it easier to distinguish between sarcoidosis and another condition that produces granulomas.

What do my Angiotensin Converting Enzyme test results mean?

If other diseases have been ruled out, an elevated ACE level in a person with clinical signs suggestive of sarcoidosis indicates that the person most likely has an active case of the disease. In 50% to 80% of those with active sarcoidosis, the ACE level will be raised. Finding a high ACE level contributes to the diagnosis's confirmation.

Sarcoidosis can exist without an elevated ACE level, thus a normal ACE level cannot be used to rule it out. Sarcoidosis patients that have normal ACE levels may have an inactive form of the disease, have been diagnosed with it early, or have cells that do not make excess ACE. Chronic sarcoidosis patients are also less likely to have increased ACE levels.

An initial high ACE level that gradually declines over time is typically indicative of a favorable prognosis and a remission brought about by therapy or spontaneously. On the other hand, an increasing level of ACE may point to either a developing disease process or disease activity that is not responding to treatment.

Most Common Questions About the Angiotensin Converting Enzyme test:

Purpose and Indications for the Angiotensin Converting Enzyme Test

Why is the Angiotensin Converting Enzyme test ordered?

The Angiotensin Converting Enzyme (ACE) test is often ordered to help diagnose and monitor sarcoidosis, a disease that causes inflammation and the formation of granulomas in various organs. Elevated ACE levels can suggest the presence or increased activity of the disease.

Who should get an Angiotensin Converting Enzyme test?

Those with symptoms suggestive of sarcoidosis, such as persistent cough, shortness of breath, or chest pain, might be recommended to undergo the ACE test. It can also be ordered for patients already diagnosed with sarcoidosis to monitor disease activity.

Clinical Significance of Test Results

What do elevated levels of ACE indicate?

While elevated ACE levels can be indicative of sarcoidosis, they can also be seen in other conditions such as Gaucher disease, hyperthyroidism, and other granulomatous diseases. It's important to interpret ACE levels in conjunction with clinical symptoms and other diagnostic tests.

If ACE levels decrease during treatment, what does it signify?

A decrease in ACE levels during treatment for sarcoidosis often indicates a favorable response to treatment and can suggest a reduction in the overall inflammatory activity of the disease.

Conditions and Medications Influencing the Test

Are there conditions other than sarcoidosis that can influence ACE levels?

Yes, apart from sarcoidosis, conditions like Gaucher disease, hyperthyroidism, and certain granulomatous diseases can elevate ACE levels. Additionally, some lung infections and diseases can also impact ACE levels.

Can medications influence Angiotensin Converting Enzyme test outcomes?

Certain medications, such as ACE inhibitors used for treating high blood pressure, can significantly affect ACE levels, leading to falsely low values. It's crucial for patients to inform their healthcare provider about any medications or supplements they are taking.

Dietary Influence and Recommendations

Do diet and nutrition affect the Angiotensin Converting Enzyme test results?

Generally, diet and nutrition don't have a direct influence on ACE test results. However, certain diets, like a high-salt diet that might necessitate the use of ACE inhibitors, can indirectly affect the test outcomes due to the medication's effect.

Interpretation and Follow-up

If the Angiotensin Converting Enzyme test results are inconclusive, what steps should one take next?

If the ACE test results are inconclusive, additional tests like chest X-rays, lung function tests, or even a biopsy of affected tissues might be recommended. It's crucial to view the ACE test results as a piece of the overall diagnostic puzzle.

Why might someone have normal ACE levels even if they have sarcoidosis?

Not every individual with sarcoidosis will have elevated ACE levels. The enzyme's levels can vary based on the extent and activity of the disease. Some people with sarcoidosis may have normal ACE levels, especially if their disease is not active.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.