Serum or plasma free dialyzed alpha-1 antitrypsin concentration (mass concentration)
This test measures the amount of a protein called alpha-1 antitrypsin (α1AT) in your blood, focusing on the free, dialyzable form. It helps assess your levels of this protein, which protects your lungs and liver from damage caused by enzymes.
["This test helps diagnose or monitor conditions linked to low α1AT levels, such as lung diseases or liver problems."]
Key facts at a glance
- LOINC
- 57841-9
- Short code
- RBC # Dial fld Auto
- Synonyms
- RBC # Dial fld Auto
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 4.2
- Ref high
- 5.9
- Critical range
- 2 N/A – 7 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- automated-count
- CPT
- 85041
- SNOMED
- 900000000000003001
- 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 Might Be Ordered
Your healthcare provider may order this test if you have a family history of α1AT deficiency, symptoms like chronic cough, shortness of breath, or liver issues, or if you’re at risk for lung diseases like emphysema or chronic obstructive pulmonary disease (COPD). It may also be used to monitor treatment progress or evaluate genetic testing results.
What to Expect Before the Test
No special preparation is needed for this test. You’ll typically have a blood sample drawn from a vein in your arm. If you’re taking blood thinners or have a history of bleeding disorders, let your provider know before the test.
What the Test Results Mean
Results are compared to a reference range for healthy individuals. Very low levels of free α1AT can indicate α1AT deficiency, which may increase your risk for lung or liver disease. High levels may suggest other conditions or medications affecting protein production.
Common Causes of Abnormal Results
Low levels of free α1AT can be linked to genetic mutations causing α1AT deficiency, liver disease, or certain medications. High levels might be due to inflammation, infections, or conditions affecting protein synthesis.
Reference range
Adult males: 4.2-5.9; Females: 3.8-5.1 x 10^12/LN/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Free α1AT testing is particularly important for individuals with a family history of α1AT deficiency, as it helps confirm the diagnosis and guide treatment decisions. Early detection can lead to interventions like enzyme replacement therapy or lung function monitoring to prevent complications.
Short name
Free Alpha-1 Antitrypsin (α1AT) Level
Frequently asked questions
What does a low free α1AT level mean?
How is this test different from total α1AT?
Can diet or medications affect this test?
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 17, 2026. · Read our editorial policy