Alpha-1 antitrypsin (AAT) is a protein normally found in the lungs and the bloodstream. It helps protect the lungs from the damage caused by inflammation that can lead to emphysema and chronic obstructive pulmonary disease (COPD). People whose bodies do not produce enough of this protein (AAT deficiency) are more likely to develop emphysema and to do so at a younger-than-normal age (30 to 40 years old). AAT deficiency is a rare disorder and is the only known genetic (inherited) factor that increases your risk of developing COPD.
Your doctor may suspect you have an AAT deficiency if you:1
If you’re one of the 12 million Americans diagnosed with COPD (chronic obstructive pulmonary disease), you’re at a turning point.
Though you're facing a life-threatening lung disease, knowing that you have it means you can start taking action. That puts you ahead of another 12 million Americans who don't yet know they may have COPD.
"We have no cure, no treatments that will stop progression or reverse the condition," says James Kiley, PhD, director of the lung-disease division of the National...
Have a family history of emphysema, bronchiectasis, liver disease, or inflammation of the fat under the skin (necrotizing panniculitis).
Have bronchiectasis without an evident cause.
An AAT deficiency test measures the level of AAT in the blood. The test is not routinely done in most people with COPD. But the American Thoracic Society and the European Respiratory Society recommend testing for an AAT deficiency for people who have:1
Symptoms of COPD and have been diagnosed with emphysema or COPD.
Asthma with airflow blockage that is not completely resolved after treatment with medicine that opens the lung airways (bronchodilators).
Unexplained liver disease.
No symptoms, but lung tests show obstruction, and risk factors such as smoking are present.
A brother or sister who is AAT-deficient.
Screening for an AAT deficiency in the general public is not currently recommended.1
It is extremely important that you do not smoke if you have an AAT deficiency. Smokers with this condition may suffer devastating disease at a young age. People with this condition who have never smoked usually do not have significant symptoms at any age.
Treatment for COPD may include medicines to help you breathe easier. It may also include pulmonary rehabilitation. This means learning exercise, eating, and breathing tips and other ways to help yourself stay as healthy and strong as you can. And your doctor may suggest that you have injections of man-made alpha-1 antitrypsin protein (also called an alpha-1 proteinase inhibitor) that has been obtained from human plasma. Examples include Aralast, Prolastin, and Zemaira. To be considered for this treatment, you must meet the following guidelines:
Your blood levels of the alpha-1 antitrypsin enzyme are less than 11 µmol/L (micromoles per liter).
DNA testing shows that your body does not produce enough of the enzyme or produces an enzyme that does not work properly.
You have difficulty breathing because of COPD or emphysema.
Injections of replacement alpha-1 antitrypsin are given either weekly or every 2 to 4 weeks. Benefits of the therapy are not clear at this time.
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WebMD Medical Reference from Healthwise
January 24, 2014
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