Alpha-1 Antitrypsin (Serum) Concentration
This test measures the amount of Alpha-1 Antitrypsin, a protein produced by the liver that helps protect the lungs from damage caused by enzymes released during inflammation.
["A1AT levels can help identify genetic conditions affecting lung or liver health."]
Key facts at a glance
- LOINC
- 31652-1
- Short code
- Deprecated S pneum6+26 Ab sp1 Ser-aCnc
- Synonyms
- Deprecated S pneum6+26 Ab sp1 Ser-aCnc
- Category
- coagulation
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why is this test done?
Your healthcare provider may order this test if you have symptoms like chronic cough, shortness of breath, or liver issues, or if you have a family history of Alpha-1 Antitrypsin deficiency—a genetic condition that can lead to lung disease (like emphysema) or liver disease.
What does a low or high level mean?
Low levels may indicate Alpha-1 Antitrypsin deficiency, which can increase your risk of lung or liver problems. High levels are less common but may be seen in certain liver diseases or during pregnancy.
How is this test performed?
A blood sample is taken from a vein in your arm. The blood is sent to a lab where it is processed to obtain serum, and the Alpha-1 Antitrypsin protein is measured using an immunoassay method.
What can affect test results?
Factors like smoking, certain medications, liver disease, or pregnancy can influence Alpha-1 Antitrypsin levels. It’s important to inform your doctor about all medications or supplements you’re taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical significance: Alpha-1 Antitrypsin deficiency is a hereditary condition that can lead to progressive lung disease (e.g., emphysema) or chronic liver disease. Early detection through blood testing allows for monitoring and potential interventions to manage symptoms and slow disease progression.
Short name
Alpha-1 Antitrypsin (A1AT) Level
Frequently asked questions
What does an abnormal result mean?
How often should I get this test?
Can lifestyle changes affect this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy