Learn About Alpha-1 Antitrypsin Deficiency (AATD)
Alpha-1 antitrypsin (AAT) deficiency is a condition in which the body does not make enough of AAT, a protein that protects the lungs and liver from damage. The condition can lead to chronic obstructive pulmonary disease (COPD) and liver disease (cirrhosis).
AAT deficiency; Alpha-1 protease deficiency; COPD - alpha-1 antitrypsin deficiency; Cirrhosis - alpha-1 antitrypsin deficiency
AAT is a type of protein called a protease inhibitor. AAT is made in the liver and it works to protect the lungs and liver.
AAT deficiency means there is not enough of this protein in the body. It is caused by a genetic defect. The condition is most common among Europeans and North Americans of European descent.
Adults with severe AAT deficiency will develop emphysema, sometimes before 40 years of age. Smoking can increase the risk for emphysema and make it occur earlier.
Symptoms may include any of the following:
- Shortness of breath with and without exertion, and other symptoms of COPD
- Symptoms of liver failure
- Loss of weight without trying
- Wheezing
- Coughing
Treatment for AAT deficiency involves replacing the missing AAT protein. The protein is given through a vein each week or every 4 weeks. This is only slightly effective at preventing more lung damage in people without end-stage disease. This procedure is called augmentation therapy.
If you smoke, you need to quit.
Other treatments are also used for COPD and cirrhosis.
Lung transplant can be used for severe lung disease, and liver transplant can be used for severe cirrhosis.
Some people with this deficiency will not develop liver or lung disease. If you quit smoking, you can slow the progression of the lung disease.
COPD and cirrhosis can be life threatening.
Complications of AAT deficiency include:
- Bronchiectasis (damage of the large airways)
- COPD
- Liver failure or cancer
Contact your provider if you develop symptoms of AAT deficiency.
Published Date: July 31, 2022
Published By: Denis Hadjiliadis, MD, MHS, Paul F. Harron, Jr. Professor of Medicine, Pulmonary, Allergy, and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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