Serum or Plasma Alpha-1 Antitrypsin (A1AT) Concentration
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.
["Alpha-1 Antitrypsin helps prevent lung disease and supports immune function."]
Key facts at a glance
- LOINC
- 10443-0
- Short code
- CD43
- Synonyms
- CD43 Ag Tiss Ql ImStn
- Category
- chemistry
- Sample
- serum
- Container
- 10% neutral buffered formalin container for tissue specimen
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- immune-stain
- CPT
- 88342
- SNOMED
- 399075003
- Specimen volume
- Adequate tissue biopsy (minimum 0.5 cm³ of representative lesional tissue)
- Stability
- Formalin-fixed paraffin-embedded (FFPE) tissue: Indefinite at room temperature. Fresh tissue: 24-48 hours refrigerated; deliver promptly to pathology lab.
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 24–72 hours
- Order
- routine
Why This Test Is Done
Your healthcare provider may order this test to check for low levels of Alpha-1 Antitrypsin, which can increase your risk of lung diseases like emphysema or chronic obstructive pulmonary disease (COPD). It may also be used to monitor these conditions or evaluate symptoms such as persistent coughing, shortness of breath, or recurrent lung infections.
What to Expect Before the Test
No special preparation is usually needed. You may have blood drawn from a vein in your arm. If you’re taking blood from your own arm, follow your healthcare provider’s instructions for safety and comfort.
What the Test Results Mean
Results are compared to a standard range for healthy adults. Low levels may indicate genetic disorders (like Alpha-1 Antitrypsin Deficiency) or liver disease. High levels might be due to liver problems or certain medications.
Common Conditions Linked to Results
Low levels of Alpha-1 Antitrypsin are strongly linked to lung diseases, including emphysema and chronic bronchitis. It can also affect liver function and increase susceptibility to infections.
Reference range
Interpreted by pathologist: Positive or Negative staining. Normal tissue: T lymphocytes show positive membranous staining; myeloid cells show variable staining. Clinical correlation required.N/A
No special patient preparation required for tissue specimens. Surgical or biopsy tissue is obtained by the clinician and submitted in appropriate fixative.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical significance: Alpha-1 Antitrypsin deficiency is a hereditary condition that can lead to progressive lung damage and liver disease. Early detection through testing helps manage symptoms and prevent complications. Monitoring levels over time is important for patients with known deficiency or those at risk.
Short name
Alpha-1 Antitrypsin Level
Frequently asked questions
What causes low Alpha-1 Antitrypsin levels?
How often should I get this test?
Can diet or supplements affect Alpha-1 Antitrypsin levels?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
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.
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