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Serum or Plasma Alpha-1 Antitrypsin (A1AT) 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 helps prevent lung and liver diseases; low levels may indicate genetic risk or lung damage."]

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

Key facts at a glance

LOINC
11907-3
Short code
GA from BPD.Sabbagha78
Synonyms
GA from BPD.Sabbagha78
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
us-estimated-from-bpd-sabbagha
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 doctor may order this test if you have symptoms like chronic cough, shortness of breath, or liver problems. It’s also used to screen for genetic conditions that affect this protein, especially in families with a history of lung diseases like emphysema or chronic obstructive pulmonary disease (COPD).

What to Expect Before the Test

No special preparation is needed, but you may fast for 8–12 hours before the blood draw if instructed. Bring any medications you’re taking to your appointment.

How the Test Works

A small sample of blood is taken from a vein, usually in your arm. The sample is sent to a lab where it is analyzed to measure Alpha-1 Antitrypsin concentration using an immunoassay method.

Possible Results and Interpretation

Results are compared to a reference range specific to your age and sex. Low levels may suggest genetic mutations, lung disease, or liver conditions. High levels may indicate liver disease or certain inflammatory conditions.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance

Short name

Alpha-1 Antitrypsin

Frequently asked questions

What Does a Low Level Mean?
Low Alpha-1 Antitrypsin levels can increase your risk of lung diseases like emphysema or chronic bronchitis, especially if you have a family history of the condition. It may also indicate liver disease or certain inflammatory disorders.
What Does a High Level Mean?
Elevated levels can sometimes be linked to liver disease, such as cirrhosis, or certain inflammatory conditions. However, high levels alone may not cause symptoms and often require further evaluation.
How Often Should I Get This Test?
Your doctor will determine the frequency based on your symptoms, medical history, and risk factors. Regular monitoring may be recommended if you have a genetic predisposition or known lung/liver conditions.
  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