Alpha-1 Antitrypsin

AAT is made by your liver. It helps protect your lungs from inflammation and irritating substances you might breathe in, such as smoke. If your liver doesn't make enough AAT, your lungs may be more easily damaged from smoking, pollution, or dust from the environment. This can lead to a serious lung condition called chronic obstructive pulmonary disease (COPD). AAT deficiency may also cause a liver disease called cirrhosis. This is more common in children who have AAT deficiency.

AAT deficiency is a genetic disorder. That means it's caused by changes in your genes, which may also be called gene variants or mutations.

Genes carry information that controls what you look like and how your body works. AAT deficiency is caused by changes in the SERPINA1 gene, which carries instructions for making the AAT protein. These gene changes are inherited from your parents, so AAT deficiency tends to run in families.

AAT levels can also rise temporarily in normal pregnancy and in many conditions involving inflammation, including chronic lung disease, hereditary angioedema, certain liver, kidney, stomach, and pancreas problems, diabetes, some cancers, and rheumatic diseases.

If your AAT blood levels are low, it may mean you have AAT deficiency. Other causes of low AAT include emphysema, advanced liver disease (cirrhosis), respiratory distress in newborns, kidney problems with protein loss (nephrosis), and severe malnutrition or wasting (cachexia). To confirm a diagnosis of AAT deficiency, you'll need a follow-up genetic test that looks at which AAT gene variants you have and whether you carry one or two affected copies.

If that testing shows that you have AAT deficiency, your provider may recommend additional testing to evaluate your lung and liver function.

Higher-than-usual AAT levels are not specific to one condition. They can be seen in normal pregnancy and in a range of inflammatory conditions, including some lung, liver, kidney, and rheumatic diseases.

There is no cure for AAT deficiency. But treatments can help prevent your condition from getting worse. Your exact treatment will depend on your symptoms. Your provider can also recommend steps you can take to stay as healthy as possible.