Alpha-1 antitrypsin deficiency (also known as Alpha-1, antitrypsin deficiency disorder, or A1AD), is a genetic disorder—it is inherited from a parent. A1AD primarily affects the lungs and liver . Often, people with alpha-1 antitrypsin deficiency will most often develop the symptoms of lung problems between the ages of 20 and 50.
In some cases, oxygen therapy may be required in addition to inhaled and other medications. 
What is Alpha-1 Antitrypsin?
Alpha-1 antitrypsin is a protein that is produced by the liver and prevents the lungs from a specific enzyme. This enzyme is responsible for getting rid of damaged or aging cells or bacteria in the lungs, to keep the lungs functioning properly. Alpha-1 antitrypsin works to keep this enzyme “in check,” to ensure it does not destroy healthy cells. In alpha-1 antitrypsin deficiency, there is not enough of this protective protein to defend against these “clean up” enzymes—when there is not enough alpha-1 antitrypsin present, the enzyme proceeds to damage healthy lung tissue. 
How is Alpha-1 Antitrypsin Deficiency diagnosed?
A1AD is most often first diagnosed—or misdiagnosed—as emphysema. Usually, emphysema affects older adults, but in A1AD, the lung damage can mimic emphysema in those who are younger and are non-smokers. The lung damage of A1AD mimics that of emphysema, but it may be misdiagnosed as asthma. As lung disease progresses, other forms of lung disease may develop on top of the emphysema symptoms, such as asthma, chronic bronchitis, or bronchiectasis. It may also be diagnosed first as liver disease such as cirrhosis and hepatoma. 
How Many People Have Alpha-1 Antitrypsin Deficiency?
It can take a long time to narrow down a person has A1AD—often diagnoses take up to 8 years.  Most people have to visit many doctors before they are tested for alpha-1 antitrypsin deficiency—one study cited only 25% are correctly diagnosed with A1AD by their first physician. 
At least 100,000 people in the US have A1AD. Given the difficulty of getting a correct diagnosis, A1AD may be under-reported. 19 million people are carriers of the A1AD gene in the United States. 
The most important tips for managing A1AD are to avoid things that may make your disease worse—as A1AD affects the lungs and liver, this means quitting smoking and limiting alcohol intake to keep these organs functioning as well as possible and slow their decline.  If you have been diagnosed with A1AD, it is extremely important to quit smoking. It is also important to avoid air pollution, chemical gases, dust, and ozone—your doctor will provide steps to take to prevent exposure.  And, as with all chronic diseases—and important for all!—maintaining a healthy diet and exercising regularly can help you stay stronger and in overall better health, including with A1AD.
Sticking with A1AD treatments as prescribed by your doctor is also extremely important. Weekly infusions of alpha-1 antitrypsin, medications to assist with breathing, oxygen therapy, and in some cases, organ transplantation, all can help to manage alpha-1 antitrypsin deficiency.
Information on this page is for reference and educational purposes only. For more information about Alpha-1 Antitrypsin Deficiency, talk to your doctor or primary care provider.
Page last updated: October 22, 2018
 National Institutes of Health - Genetics Home Reference. Alpha-1 Antitrypsin Deficiency. https://ghr.nlm.nih.gov/condition/alpha-1-antitrypsin-deficiency
 National Organization for Rare Disorders. Alpha-1 Antitrypsin Deficiency. https://rarediseases.org/rare-diseases/alpha-1-antitrypsin-deficiency/
 American Thoracic Society Journals. Detecting Alpha-1 Antitrypsin Deficiency. https://www.atsjournals.org/doi/pdf/10.1513/AnnalsATS.201506-349KV
 Alpha1 Foundation. Fast Facts Card. https://www.alpha1.org/Portals/0/Documents/Alpha-1-Fast-Facts-Card_COPD.pdf
 Alpha1 Foundation. What Now? Living with Alpha-1. https://www.alpha1.org/Newly-Diagnosed/Living-with-Alpha-1/What-Now
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