Question: What is (are) Alpha-1 antitrypsin deficiency ?
Answer: Alpha-1 antitrypsin deficiency (AATD) is a disorder that causes a deficiency or absence of the alpha-1 antitrypsin (AAT) protein in the blood. AAT is made in the liver and sent through the bloodstream to the lungs, to protect the lungs from damage. Having low levels of ATT (or no ATT) can allow the lungs to become damaged, making breathing hard. Age of onset and severity of AATD can vary based on how much ATT an affected person is missing. In adults, symptoms may include shortness of breath; reduced ability to exercise; wheezing; respiratory infections; fatigue; vision problems; and weight loss. Some people have chronic obstructive pulmonary disease (COPD) or asthma. Liver disease (cirrhosis) may occur in affected children or adults. Rarely, AATD can cause a skin condition called panniculitis. AATD is caused by mutations in the SERPINA1 gene and is inherited in a codominant manner. Treatment is based on each person's symptoms and may include bronchodilators; antibiotics for upper respiratory tract infections; intravenous therapy of AAT; and/or lung transplantation in severe cases.
Source: GARD

Question: How to diagnose Alpha-1 antitrypsin deficiency ?
Answer: How is alpha-1 antitrypsin deficiency diagnosed? Alpha-1 antitrypsin deficiency (AATD) may first be suspected in people with evidence of liver disease at any age, or lung disease (such as emphysema), especially when there is no obvious cause or it is diagnosed at a younger age. Confirming the diagnosis involves a blood test showing a low serum concentration of the alpha-1 antitrypsin (AAT) protein, and either: detecting a functionally deficient AAT protein variant by isoelectric focusing (a method for detecting mutations); or detecting SERPINA1 gene mutations on both copies of the gene with molecular genetic testing. (This confirms the diagnosis when the above-mentioned tests are not performed or their results are not in agreement.) Specialists involved in the diagnosis may include primary care doctors, pulmonologists (lung specialists), and/or hepatologists (liver specialists).
Source: GARD