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What is Alpha-1 Antitrypsin?
Alpha-1 antitrypsin is an important protein produced by the liver. Once the protein is released into the the bloodstream and travels to the lungs, it protects the lungs from the destructive actions of common illnesses and exposures, particularly tobacco smoke.







What is Alpha-1 Antitrypsin Deficiency?
Alpha-1 antitrypsin deficiency is an inherited disorder that may cause lung or liver disease. Adults with a deficiency of this protective protein often suffer from progressive lung damage known as Emphysema. While the common form of Emphysema is seen in otherwise healthy individuals who have smoked for many years, this Alpha-1 antitrypsin deficiency form of Emphysema may occur at an unusually young age and often after only minimal exposure to tobacco smoke.







What is Emphysema?
Emphysema is an irreversible condition that results from the destruction of air sacs in lungs. These air sacs, known as alveoli, allow for the absorption of oxygen into the bloodstream and for the elimination of carbon dioxide waste. If they are destroyed, shortness of breath and a chronic cough may result. Not everyone with Alpha-1 antitrypsin deficiency will develop emphysema. In most cases the amount of alpha-1 antitrypsin present will be enough to protect the lung from severe destruction.







What is Cirrhosis?
Cirrhosis is a chronic degenerative disease of the liver. Alpha-1 antitrypsin deficiency is a risk factor for cirrhosis. The liver deteriorates as the lobes become bibulous and fat accumulates. The liver becomes unable to detoxify drugs and alcohol. Vitamin absorption is inhibited. Both gastrointestinal bilirubin and hormonal metabolic functions are affected. Symptoms of cirrhosis include nausea, weakness, abdominal pain, weight loss and flatulence.




What is Panniculitis?
Panniculitis is an inflamation of the fat beneath the skin, causing the skin to harden and form lumps, patches or lesions. People with Alpha-1 antitrypsin deficiency have an increased risk of developing Panniculitis.





Risk Factors
Smoking is the number one risk factor. Cigarette smoke renders the available alpha-1 antitrypsin useless. Smoking cessation can improve the survival rate.
Avoiding any type of irritant, bacteria or virus will decrease further lung disease.




























































How is Alpha-1 Antitrypsin Deficiency Diagnosed?



Diagnosis is made using a simple blood test to detect levels of AAT circulating in your blood serum. Most, but not all people with levels less than 30% of normal will develop emphysema. Levels above 30% of normal are seen to give adequate protection unless the person is a heavy smoker. A blood test is recommended if you have relatives, especially siblings, who have been diagnosed with A1AD or if there is a family history of early emphysema, with or without smoking.
Phenotyping is only done when levels come back low. This blood will be sent to Edmonton or Vancouver for analyzing.
MM refers to the normal gene.
S, Z, and Null genes are the most common ones that cause A1AD.
Null gene produces no detectable levels of AAT. They are at greatest risk of developing emphysema, yet none have suffered liver damage as a result of A1AD.

Lab normals vary across Canada for AAT plasma levels. To interpret your results, you must know the normal for your specific lab (shown on report). One example seen may be a normal of 0.9 - 2.5 g/L. A level below 11 micromoles (µM) for AAT plasma is often found on USA lab results.











How did I inherit this deficiency?
You inherit one gene from each parent at birth from a choice of two. If one of your parents had normal levels of AAT (ie phenotype MM) and the other had very low levels (ie phenotype ZZ) then your phenotype would be MZ (one gene from each parent) and your lungs would be protected but you would still be a carrier. If both parents have the MM or ZZ phenotype then you would either be MM or ZZ.
MM normal level
MS 80% of normal
MZ 60% of normal
SZ 40% of normal
ZZ 10% of normal level











Treatments Available
Present treatment is to help relieve symptoms, especially breathlessness. The use of inhaled bronchodilators such as Ventolin, Atrovent and Bricanyl often help.
Intravenous (injection) replacement therapy with a purified blood product Prolastin has been approved for prescription use and is targeted at deficient subjects who have evidence of significant pulmonary diseases. However, the role of this replacement therapy remains controversial. Further studies need to be undertaken.

Lung Volume Reduction is also done to remove damaged, overinflated portions of the lungs. This is done to create more room for the diaphragm to move and for the normal parts of the lungs to inflate and deflate. Often, however the lung damage is so diffuse with little good lung to expand to improve the lung function.
Lung transplants have been done on severe end stage lung disease with some improvements in lung function but there is considerable risk.


Genetics
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