Should you get tested for Alpha-1?
The common risk factors for Alpha-1 are:
- A family history of Alpha-1 such as if a parent, child or sibling is diagnosed with the condition.
- An individual with any one of these conditions: COPD, emphysema, chronic bronchitis or bronchiectasis.
- If you have asthma that is not completely reversible, even with aggressive medical treatment.
- If you have unexplained liver disease.
- A family history of lung or liver disease.
- The skin disease panniculitis.
If you have one or more of the above risk factors, it is recommended that you should be tested for Alpha-1.
Testing for Alpha-1
There are three types of simple laboratory tests for Alpha-1. First, you can test for the amount of AAT protein in the blood. This is often called a serum level.
Second, you can evaluate the AAT protein in the blood for its chemical characteristics since deficient AAT protein is different than normal. This is called Pi-typing or phenotyping.
Finally, you can look at the AAT genes and test them for common abnormalities. This is called genotyping. It is often helpful to do two or even all of these tests in order to be sure of an Alpha-1 diagnosis.
The normal range of AAT in the blood can be as high as 400 mg/dL or 4 grams in each quart of blood. The level can be measured using one of a variety of techniques but, most commonly, antibodies against AAT are used to quantify the amount of AAT in the serum. The results are expressed either in mg/dL (milligrams per 100 cc of blood) or in μM (micromoles).
Local labs tend to use the mg/dL units and the normal range tends to vary from lab to lab, with the low end of the normal range varying from 70 to 200 mg/dL. In general, individuals with severe Alpha-1 deficiencies tend to have an AAT level of less than 50 mg/dL. The national testing laboratories use the μM system, and the low end of the normal range is approximately 28 μM in this system. Individuals with a level less than 11 μM are considered to have severe deficiency of AAT.
You can get more information on Alpha-1 testing from a variety of resources:
- Alpha-1 Foundation offers free, confidential testing information
- The CDC has a free Family Health Portrait Tool
If you have any further questions, please contact us.