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Alpha-1 Antitrypsin (A1AT) Serum Concentration by Immunoassay

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 lungs and other organs from damage caused by enzymes released during inflammation.

Quick summary

["A1AT helps prevent lung diseases like emphysema and supports liver health."]

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

Key facts at a glance

LOINC
49523-4
Short code
FLUAV H3 RNA Islt Ql NAA+probe
Synonyms
FLUAV H3 RNA Islt Ql NAA+probe
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
probe-amp-tar
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 of lung disease (such as chronic coughing, shortness of breath), a family history of Alpha-1 Antitrypsin deficiency, or if you have liver problems. It can also help diagnose or monitor conditions like chronic obstructive pulmonary disease (COPD) or cirrhosis.

What Does the Test Involve?

A blood sample is drawn from a vein, usually in your arm. The sample is sent to a lab where it is tested for Alpha-1 Antitrypsin levels using an immunoassay method, which detects the protein’s presence and concentration.

What Are Possible Results?

Results may indicate normal levels, low levels (which could suggest Alpha-1 Antitrypsin deficiency), or other variations. Your doctor will interpret the results in relation to your symptoms and medical history.

What Are the Risks?

The most common risk is mild discomfort or bruising at the needle insertion site. Rarely, there may be a slight reaction at the injection site or a minor allergic response to the blood draw process.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance: Alpha-1 Antitrypsin Deficiency

Short name

A1AT Level

Frequently asked questions

What does a low Alpha-1 Antitrypsin level mean?
A low level may indicate Alpha-1 Antitrypsin deficiency, a genetic condition that can lead to lung diseases (like emphysema) or liver disease over time. Early diagnosis helps manage symptoms and prevent complications.
How often should I get this test?
Your doctor will determine the frequency based on your symptoms, medical history, and risk factors. Some people with a known deficiency may need monitoring more often, while others may only need testing if symptoms arise.
Can lifestyle changes affect this test result?
Yes, certain medications (like steroids) or smoking can influence Alpha-1 Antitrypsin levels. Avoiding smoking and following your doctor’s advice for managing chronic conditions can help maintain more stable results.
  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