Alpha-1 antitrypsin deficiency (AATD) is an inherited condition that can affect both lung and liver health. Because the condition is caused by changes in the SERPINA1 gene, the amount and function of alpha-1 antitrypsin in the body can vary from person to person. Some individuals have few or no symptoms, while others may develop emphysema, COPD, liver disease, or other complications. Early recognition can be important because lung damage may progress more quickly when additional risk factors are present. Smoking is one of the most significant preventable factors associated with worsening lung disease in people with AATD.
Alpha-1 antitrypsin is produced primarily in the liver and travels through the bloodstream to protect tissues, particularly the lungs, from enzymes that can damage lung structure.
AATD results from inherited changes in the SERPINA1 gene. Certain variants can reduce the amount of alpha-1 antitrypsin reaching the lungs, while some variants can also cause abnormal protein to accumulate inside liver cells.
Lung symptoms may include:
Some people develop emphysema or chronic obstructive pulmonary disease (COPD) at a younger age than expected.
Liver-related symptoms can include abnormal liver enzymes, fatty liver, inflammation, cirrhosis, or other liver complications.
Low levels of functional alpha-1 antitrypsin can leave lung tissue less protected against enzymes released during inflammation.
Over time, this can contribute to destruction of the air sacs and development of emphysema.
Smoking can substantially increase lung damage in people with AATD, making avoidance of tobacco smoke particularly important.
Certain AATD variants can cause abnormal alpha-1 antitrypsin proteins to accumulate within liver cells.
This can contribute to liver inflammation and scarring.
Possible complications include:
Not everyone with AATD develops liver disease.
AATD is inherited and can occur in people of different ethnic backgrounds.
A family history of AATD, unexplained emphysema at a relatively young age, unexplained liver disease, or COPD without a typical risk factor can raise suspicion.
Because it is genetic, family members of someone diagnosed with AATD may also be offered testing.
Testing usually begins with a blood test that measures the amount of alpha-1 antitrypsin in the bloodstream.
Additional testing may include:
The combination of protein levels and genetic information can help determine the type of deficiency.
There is currently no simple treatment that removes the inherited genetic cause, but several approaches can help protect lung and liver health.
Avoiding cigarettes and secondhand smoke is one of the most important steps for protecting lung function.
People with AATD should also minimize exposure to occupational dust, fumes, and other lung irritants when possible.
Recommended vaccinations can help reduce the risk of respiratory infections that may worsen underlying lung disease.
Depending on age and individual circumstances, healthcare professionals may recommend influenza, pneumococcal, COVID-19, hepatitis, and other vaccines.
People with AATD-related airflow obstruction may receive treatments commonly used for COPD, including inhaled bronchodilators and other medicines when appropriate.
Pulmonary rehabilitation and physical activity can also support exercise capacity and quality of life.
Intravenous alpha-1 proteinase inhibitor therapy, also called augmentation therapy, can increase circulating alpha-1 antitrypsin levels.
It is primarily considered for selected people with severe AATD and established airflow obstruction. Eligibility depends on factors such as genotype, blood alpha-1 antitrypsin concentration, lung function, and clinical guidelines.
Augmentation therapy does not replace smoking cessation or standard treatment for COPD.
There is currently no augmentation therapy that reliably prevents or reverses liver disease caused by AATD.
Management focuses on monitoring liver health, avoiding substances that can further damage the liver, treating complications, and managing advanced disease when necessary.
For severe liver failure, liver transplantation may be considered.
Regular physical activity can be beneficial for people with AATD-related lung disease.
An individualized exercise program may help maintain muscle strength and cardiovascular fitness.
People with significant breathing problems may benefit from pulmonary rehabilitation, where exercise and breathing strategies are supervised by trained professionals.
Long-term monitoring may include periodic evaluation of lung and liver health.
Depending on the individual's condition, clinicians may monitor:
Monitoring helps identify changes early and allows treatment to be adjusted when necessary.
The inherited deficiency itself cannot be prevented after conception because it results from genetic variants.
However, some of the complications can potentially be reduced.
Avoiding smoking, limiting exposure to lung irritants, maintaining recommended vaccinations, exercising appropriately, and receiving regular medical care can help protect lung function.
Alpha-1 antitrypsin deficiency is an inherited condition that can affect both the lungs and liver. It can contribute to emphysema, COPD, liver inflammation, fibrosis, and cirrhosis in some individuals.
Diagnosis generally involves blood testing followed by genetic or protein-typing tests when appropriate. Treatment focuses on protecting lung function, avoiding tobacco smoke, managing respiratory disease, monitoring liver health, and considering augmentation therapy for selected patients with severe deficiency and lung disease.
Because AATD can run in families, genetic testing and counseling may also be appropriate for relatives of people who receive a confirmed diagnosis.