What is this test?
Alpha-1-antitrypsin is a protein from the liver that protects lung tissue from inflammatory damage.
Why might it be ordered?
- For unusually early lung disease, emphysema or a relevant family history.
- In unexplained liver disease in children or adults.
What sample is needed?
A healthcare professional collects a venous blood sample. Depending on the method, the laboratory uses serum or plasma.
How should you prepare?
Tell the laboratory about all medicines, hormone treatments, vitamins and supplements you take. Do not stop or change treatment unless your clinician tells you to. Follow any instructions about fasting and the time of collection.
How should you understand the result?
A low value may point to an inherited deficiency and usually requires phenotype or genetic testing. Inflammation can temporarily raise the value. Your result is interpreted using the reference interval on the laboratory report and in the context of your symptoms, medical history and other test findings.
Sources and editorial status
This patient-facing text is an editorial draft. It should be approved by a laboratory physician before official publication.