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Alpha-1 Antitrypsin (A1AT) Serum Concentration

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

This test measures the level of Alpha-1 Antitrypsin, a protein produced by the liver that helps protect the lungs and other organs from damage caused by enzymes released during inflammation.

Quick summary

["Alpha-1 Antitrypsin levels help assess risk for lung diseases like emphysema or chronic obstructive pulmonary disease (COPD)."]

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

Key facts at a glance

LOINC
51390-3
Short code
Deprecated Abd XR AP+Lat
Synonyms
Deprecated Abd XR AP+Lat
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
xr
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 for Your Health

Alpha-1 Antitrypsin is crucial for maintaining lung and liver health. Low levels can increase your risk of developing serious lung conditions, such as emphysema, especially if you have a family history of lung disease or smoke. This test helps doctors monitor your risk and guide treatment decisions if needed.

What to Expect Before the Test

No special preparation is required for this blood test. You may have a small needle inserted into your arm to draw a blood sample. If you’re nervous, let your healthcare provider know—they can offer tips to make it more comfortable.

What the Results Might Mean

Your results will show whether your Alpha-1 Antitrypsin levels are within the normal range or lower than expected. Very low levels may indicate a genetic condition called Alpha-1 Antitrypsin Deficiency, which can affect lung and liver function over time.

Common Causes of Abnormal Results

Low Alpha-1 Antitrypsin levels can occur due to genetic mutations, chronic liver disease, or certain medications. High levels may be seen in some liver disorders or during pregnancy, but this is less common.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance: Understanding Your Findings

Short name

Alpha-1 Antitrypsin

Frequently asked questions

Why might my doctor order this test?
Your doctor may recommend this test if you have a family history of lung diseases, symptoms like persistent coughing or shortness of breath, or if you’ve been diagnosed with liver issues. It’s also sometimes checked in people with unexplained lung problems or those at higher risk for COPD.
What does a low result mean for my health?
A low result suggests you may have Alpha-1 Antitrypsin Deficiency, which can increase your risk of lung diseases like emphysema. Your doctor will discuss next steps, such as lifestyle changes, monitoring, or potential treatments to protect your lungs.
Can diet or lifestyle changes affect this test result?
While diet and exercise don’t directly change Alpha-1 Antitrypsin levels, they can impact overall health. If you have a genetic risk, avoiding smoking, managing lung conditions, and following your doctor’s advice can help slow disease progression.
  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