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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 or injury.

Quick summary

["Alpha-1 Antitrypsin helps prevent lung disease and supports immune function; low levels may indicate genetic disorders or lung/lung-related conditions."]

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

Key facts at a glance

LOINC
90295-7
Short code
RalA Ab SerPl IA-aCnc
Synonyms
RalA Ab SerPl IA-aCnc
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
ia
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 Is Done

Doctors may order this test to check for genetic conditions like Alpha-1 Antitrypsin Deficiency, which can lead to chronic lung diseases (e.g., emphysema) or liver problems. It may also be used in people with known lung or liver disease to monitor protein levels.

What to Expect Before the Test

No special preparation is needed. You may have a blood sample drawn from a vein in your arm, or if plasma is used, it could be collected from a blood draw or specialized tube. Urine or saliva tests are not applicable for this test.

What the Test Results Mean

Results show the concentration of Alpha-1 Antitrypsin in your blood. Low levels may signal a genetic disorder or other health conditions affecting protein production. High levels may be seen in certain liver diseases or other metabolic conditions.

Common Conditions Monitored

Low Alpha-1 Antitrypsin levels are linked to Alpha-1 Antitrypsin Deficiency, which can cause lung diseases like emphysema or chronic bronchitis. It may also affect liver function. Doctors use these results to guide treatment or management plans.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Alpha-1 Antitrypsin Level

Frequently asked questions

What causes my Alpha-1 Antitrypsin level to be low?
Low levels are often due to genetic mutations passed down through families. However, other conditions like liver disease, certain medications, or severe infections may temporarily lower it. If you have a family history of lung or liver disease, this test helps identify potential risks early.
How often should I get this test?
If you have Alpha-1 Antitrypsin Deficiency, your doctor may recommend regular testing to monitor lung or liver health. For others, testing may be done only if symptoms or risk factors (like smoking history) suggest a need. Follow your healthcare provider’s advice.
Can diet or lifestyle changes affect my Alpha-1 Antitrypsin levels?
While diet and lifestyle (like smoking) can impact lung health, they do not directly change the protein level itself. However, smoking can worsen lung disease symptoms linked to low Alpha-1 Antitrypsin. Avoiding smoking and maintaining a healthy lifestyle may help overall health, including lung function.
  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