Alpha-1 antitrypsin deficiency is an inherited disorder that can cause lung disease in adults and liver disease in adults and children. Alpha-1 antitrypsin (AAT) is a protein that protects the lungs. The liver usually makes the protein, and releases it into the bloodstream. Because of a gene problem, some people have little or none of it. Not having enough AAT puts you at risk of emphysema or liver problems. Three in four adults with a severe deficiency will get emphysema, some when they are younger than 40. If you smoke, you increase your risk. Children with AAT deficiency can develop liver problems that last their whole lives.

AAT deficiency can be treated but not cured. One treatment involves adding to or replacing the missing protein. A lung transplant may be an option if you are seriously ill. Staying away from cigarette smoke is crucial.

A blood test can tell if you have the deficiency. If you have it, your family members should also take the blood test.