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Serum or Plasma Alpha-1 Antitrypsin (A1AT) Concentration

Published: August 9, 2026Updated: August 16, 2026

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.

Quick summary

["Alpha-1 Antitrypsin helps prevent lung disease and liver problems; low levels may indicate genetic disorders or lung damage."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
111909-8
Short code
AE SB Endscpy
Synonyms
AE SB Endscpy
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
endoscopy
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 This Test Matters

Alpha-1 Antitrypsin (A1AT) is crucial for maintaining lung and liver health. Low levels can increase your risk of chronic lung diseases, such as emphysema, or liver diseases like cirrhosis. This test helps doctors identify if you have a genetic deficiency that may require monitoring or treatment.

What to Expect Before the Test

No special preparation is needed for this blood test. You may have a small needle inserted into your arm to draw blood. If you’re on blood thinners or have a history of bleeding issues, let your doctor know before the test.

What the Results Mean

Results show your A1AT concentration in the blood. Low levels may suggest a genetic condition (like Alpha-1 Antitrypsin Deficiency), while normal or high levels indicate healthy protein levels. Your doctor will discuss these results in relation to your symptoms and medical history.

Common Reasons for Testing

Doctors may order this test if you have symptoms of lung disease (like chronic coughing or shortness of breath), liver problems, or if you have a family history of Alpha-1 Antitrypsin Deficiency. It’s also used in screening for genetic conditions before pregnancy.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance

Short name

Alpha-1 Antitrypsin Level

Frequently asked questions

What causes low Alpha-1 Antitrypsin levels?
Low levels are often due to a genetic mutation passed down through families. Other rare causes may include liver disease or certain medications. If you have a family history of lung or liver disease, ask your doctor about genetic testing.
How is Alpha-1 Antitrypsin Deficiency treated?
Treatment focuses on managing symptoms and preventing complications. For severe cases, intravenous infusions of donor A1AT protein may be recommended. Lifestyle changes, such as avoiding smoking and managing lung infections, are also important.
Can this test be done at home?
No, this test requires a blood sample drawn in a clinical setting. If you’re concerned about A1AT levels, discuss it with your doctor—they may recommend a simple blood test.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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