A deficiency of alpha-1 antitrypsin allows substances that break down proteins (called proteolytic enzymes or proteases) to damage tissues in the body. Many individuals with the condition, however, never develop any disease associated with it. Alpha-1 antitrypsin deficiency affects both males and females of all ethnic backgrounds.
In alpha-1 antitrypsin deficiency, the genes that produce AAT are abnormal. In order to develop alpha-1 antitrypsin deficiency, an individual must inherit two abnormal AAT genes. Numerous types of AAT genes have been identified.
Symptoms
Since alpha-1 antitrypsin deficiency is inherited, it is present at birth. Individuals with the disorder are at increased risk of developing:- lung disease – damage of the lung tissues causes emphysema, a lung disease that results in shortness of breath. Emphysema may begin sooner, or be made worse, by smoking.
- liver disease – damage of the liver tissues causes cirrhosis (scarring of the liver). Excessive pressure in the portal vein that carries blood to the liver (called portal hypertension), a serious condition, may develop. Liver cancer is also a long-term risk with cirrhosis.
- panniculitis, which refers to a group of skin conditions that involve inflammation of the fat under the skin.
The World Health Organization (WHO), American Thoracic Society (ATS) and the European Respiratory Society (ERS) recommend that all individuals with chronic obstructive lung disease or unexplained liver disease be tested for alpha-1 antitrypsin deficiency.
Diagnosis
There are two types of simple laboratory blood tests for alpha-1 antitrypsin. The alpha-1 antitrypsin level in the blood can be checked. In general, individuals with apha-1 antitrypsin deficiency tend to have an AAT level of less than 50 mg/dL. Genetic testing can look for an abnormal AAT gene to help confirm the diagnosis.Treatment
Treatment focuses on maintaining and improving the health of the lungs and liver. If the liver is severely damaged, liver transplantation may be necessary. Liver damage does not usually occur in the transplanted liver, and the new liver is able to produce alpha-1 antitrypsin. Medications to treat emphysema, preventing lung infections, and getting individuals to quit smoking all help improve lung function. If the lungs are severely damaged, lung transplantation may be necessary.In addition to treatment of lung and liver disease, specific treatment of alpha-1 antitrypsin deficiency consists of weekly infusions of purified human plasma alpha-1 antitrypsin (called augmentation therapy). The goal of this treatment is to raise and maintain the levels of alpha-1 antitrypsin in the body. Several preparations, including AAT, Prolastin, Aralast and Zemaira are available for augmentation therapy.
Sources:
"Alpha1-Antitrypsin Deficiency." The Merck Manuals Online Medical Library. Feb 2003. Merck. 17 Sep 2007.
"Frequently Asked Questions about Alpha-1 Antitrypsin Deficiency." AlphaNet. 17 Sep 2007.
"Alpha-1-Antitrypsin Deficiency." Index of Rare Diseases. National Organization for Rare Disorders. 17 Sep 2007.
