Serum or Plasma Enzyme Activity for Specific Protease Inhibitor (e.g., Alpha-1 Antitrypsin)

Why This Test Might Be Ordered

Your doctor may recommend this test if you have a family history of lung diseases like emphysema or chronic obstructive pulmonary disease (COPD), liver disease, or if you have symptoms such as persistent coughing, shortness of breath, or unexplained liver issues. It can also be part of screening for genetic conditions affecting this protein.

What to Expect Before the Test

You’ll typically have a simple blood draw from a vein in your arm. No special preparation is usually needed, but your doctor may advise fasting if the test is part of a broader metabolic evaluation. Avoid smoking or strenuous activity for a few hours before the test if it relates to lung health.

What the Results Mean

Low levels of alpha-1 antitrypsin may indicate a genetic deficiency linked to lung or liver disease. High levels might be seen in certain inflammatory conditions or during pregnancy. Your doctor will interpret results in the context of your overall health and symptoms.

Common Conditions Monitored

This test is often used to diagnose or monitor conditions like alpha-1 antitrypsin deficiency, which can lead to emphysema or cirrhosis. It may also help assess liver function or guide treatment plans for chronic inflammatory diseases.