Alpha-1 Antitrypsin Deficiency Gains Awareness
The story about Kerri Evensen of Wisconsin, who discovered she had a life-threatening aneurysm while undergoing routine testing for her liver donation for her four-year-old son Auden who has alpha-1 antitrypsin deficiency, has done several things, not least of which is increased awareness of this rare disease. In fact, the state of Ohio had already officially designated November as “Alpha-1 Antitrypsin Deficiency Awareness Month” earlier this year.
What is this disease that has captured the attention of the media? Here are some things you should know about alpha-1 antitrypsin deficiency.
What is alpha-1 antitrypsin deficiency?
Alpha-1 antitrypsin deficiency is an inherited condition in which an individual receives two abnormal alpha-1 antitrypsin genes, one from each parent. It is the most common genetic cause of liver disease in children, but adults can be affected as well and may develop lung problems (e.g., emphysema) as well as liver conditions.
Individuals without the disease have two M genes (MM), while those with the disease typically have either two Z genes (ZZ) or, less often, a combination of S and Z genes (SZ). An estimated 100,000 people in the United States have the ZZ combination, while fewer individuals have the SZ combo. People with the SZ combo are less likely to experience lung or liver problems.
The abnormal genes cause the body to have an insufficient amount of a protein (alpha-1 antitrypsin, or AAT) that is produced by the liver and also protects the liver and lungs from infection and resulting inflammation and organ damage. People with the disease have abnormal AAT that cannot be released from the liver in a normal fashion, which causes it to build up and result in liver disease. A decline of AAT in the blood also can lead to lung disease, including lung cancer.
What does alpha-1 antitrypsin deficiency look like?
Not everyone who has alpha-1 antitrypsin deficiency experiences liver or lung disease. In fact, identifying the disease early and avoiding risk factors, such as smoking, can help prevent the disease from manifesting itself.
That said, there are some common signs and symptoms of the disease. When it affects the lungs, they include:
- Chronic bronchitis
- Recurring chest colds
- Shortness of breath and/or wheezing
- Allergies year round
- Asthma that does not respond to aggressive medical treatment
- Poor exercise tolerance
Signs and symptoms related to the liver include:
- Abdominal and/or leg swelling
- Vomiting blood
- Elevated liver enzymes or unexplained liver disease
Individuals with alpha-1 antitrypsin deficiency have large amounts of AAT in the liver. When the organ is unable to break down the abnormal protein, the liver becomes scarred and damaged. Currently experts have no way to prevent abnormal AAT from accumulating in the liver, which can result in serious liver disease and individuals like Auden needing a liver transplant.
An estimated 1 in every 2,500 Americans have alpha-1 antitrypsin deficiency, and about 19 million people are carriers. That means they have one normal alpha-1 gene and one defective or abnormal one. People who are carriers (e.g., MZ) can pass the defective gene to their children.
Three types of blood tests are available to identify the presence of alpha-1 antitrypsin deficiency:
- Alpha-1 genotypes, which looks at a person’s genes
- Alpha-1 antitrypsin PI, which identifies the type of AAT protein a person has
- Alpha-1 antitrypsin level, which measures the amount of AAT a person has in the blood
For additional information about alpha-1 antitrypsin deficiency, how to get tested, where to find health care and support groups, how to participate in research, and more, contact the Alpha-1 Foundation. The American Liver Foundation and the National Human Genome Research Institute are also good sources of information.
Best wishes to Auden and his mother!