Print-Friendly
Bookmarks
bookmarks-menu

Alpha-1 antitrypsin blood test

A1AT test

 

Alpha-1 antitrypsin (AAT) is a laboratory test to measure the amount of AAT in your blood. The test is also done to check for abnormal forms of AAT.

How the Test is Performed

 

A blood sample is needed.

 

How to Prepare for the Test

 

There is no special preparation.

 

How the Test will Feel

 

When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away.

 

Why the Test is Performed

 

This test is helpful in identifying a rare form of emphysema in adults and a rare form of liver disease (cirrhosis) in children and adults caused by an AAT deficiency. AAT deficiency is passed down through families. The condition causes the liver to make too little of AAT, a protein that protects the lungs and liver from damage.

Everyone has two copies of the gene that makes AAT. Most people with a lower-than-normal level of AAT have one normal gene for AAT, and one abnormal gene. People with two abnormal copies of the gene have more severe disease.

 

Normal Results

 

Normal value ranges may vary slightly among different laboratories. Talk to your health care provider about the meaning of your specific test results.

 

What Abnormal Results Mean

 

A lower-than-normal level of AAT may be associated with:

  • Damage of the large airways in the lungs (bronchiectasis)
  • Scarring of the liver (cirrhosis)
  • Chronic obstructive pulmonary disease (COPD)
  • Liver tumors
  • Yellowing of the skin and eyes due to blocked bile flow (obstructive jaundice)
  • High blood pressure in the large vein leads to the liver (portal hypertension)

 

Risks

 

There is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another, and from one side of the body to the other. Taking blood from some people may be more difficult than from others.

Other risks associated with having blood drawn are slight, but may include:

  • Excessive bleeding
  • Fainting or feeling lightheaded
  • Multiple punctures to locate veins
  • Hematoma (blood accumulating under the skin)
  • Infection (a slight risk any time the skin is broken)

 

 

References

Chernecky CC, Berger BJ. Alpha1-antitrypsin - serum. In: Chernecky CC, Berger BJ, eds. Laboratory Tests and Diagnostic Procedures. 6th ed. St Louis, MO: Elsevier Saunders; 2013:121-122.

Winnie GB, Boas SR. A1-antitrypsin deficiency and emphysema. In: Kliegman RM, Stanton BF, St. Geme JW, Schor NF, eds. Nelson Textbook of Pediatrics. 20th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 393.

Text only

 

        A Closer Look

         

        Talking to your MD

         

          Self Care

           

            Tests for Alpha-1 antitrypsin blood test

             
             

            Review Date: 7/20/2018

            Reviewed By: Allen J. Blaivas, DO, Division of Pulmonary, Critical Care, and Sleep Medicine, VA New Jersey Health Care System, Clinical Assistant Professor, Rutgers New Jersey Medical School, East Orange, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

            The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
            adam.com

             
             
             

             

             

            A.D.A.M. content is best viewed in IE9 or above, Firefox and Google Chrome browser.
            Content is best viewed in IE9 or above, Firefox and Google Chrome browser.