What is alpha-1 antitrypsin deficiency?
AAT may lead to lung conditions and lung damage. Alpha-1 antitrypsin deficiency (A1AD or AATD) is an inherited genetic disorder that occurs due to the mutation of the gene, Serpina1. This results in insufficient levels of alpha-1 antitrypsin (A1AT or AA), which is a protein that protects the lungs. It is an autosomal codominant disease, which means the inheritance of one mutated allele (a variant form a particular gene) results in mild disease whereas the inheritance of two mutated alleles results in more severe disease. This condition commonly affects the lungs and liver. The onset of lung problems typically occurs between the ages of 20 to 50. AAT is required to protect the lungs. With AAT deficiency, infections of the lungs and environmental irritants like tobacco smoke cause lung damage much faster than usual.
AAT deficiency can cause chronic obstructive pulmonary disease (COPD). COPD is a group of diseases causing an inflammatory reaction and irreversible damage in the lungs. They cause obstruction of airflow and difficulty breathing. Emphysema and chronic bronchitis are the most common diseases that makeup COPD. Emphysema is a disease of the alveoli (the tiny air sacs in the lungs). Chronic bronchitis is a disease of the bronchus (the tubes through which air passes in the lungs). The trachea can also be involved.
During inhalation, air travels through the nose and/or mouth into the trachea (windpipe). The trachea further divides into two tubes called bronchi. The bronchi branch out into smaller tubes called bronchioles. The ends of bronchioles open into little air sacs called alveoli, which aid in gaseous exchange. The alveoli are surrounded by blood vessels through which the exchange of gases, oxygen and carbon dioxide takes place.
Life expectancy in alpha-1 antitrypsin deficiency
There is no cure for the disease, but various treatment options are available to manage the disease and associated lung and liver problems. With appropriate treatment, most patients would be able to live a good life with normal life expectancy, work, play sports and exercise. The symptoms and complications of liver and lung damage can be managed medically. If patients are not diagnosed and treated appropriately, the disease can potentially lead to severe organ damage, which can be fatal.
What are the signs and symptoms of alpha-1 antitrypsin deficiency?
The disease may not present until adulthood. Most people develop symptoms between the ages of 20 to 40 years old. Some patients may have severe problems while others may have few or no symptoms.
- Shortness of breath on exertion or at rest in severe cases
- Wheezing (whistling sound while breathing)
- Frequent lung infections
- Jaundice (yellow discoloration of the eyes and skin)
- Swelling of the legs
- Dark yellow urine
- Coughing blood
- Easy bleeding and bruising
- Panniculitis are painful lumps or patches on the skin.
Signs and symptoms in babies
- Dark yellow urine
- Nose bleeding
- Enlarged abdomen due to liver enlargement
- Difficulty gaining weight
How is alpha-1 antitrypsin deficiency treated?
There is no cure for AAT deficiency, but various treatment options are available to manage the disease. Patients typically require lifelong treatment and lifestyle modifications to live a normal life and prevent complications. Treatment options include
- Augmentation or replacement therapy: This involves AAT replacement to increase it to normal levels. AAT protein is typically administered once a week intravenously (IV). The goal of replacement therapy is to protect, slow down or stop the damage of the lungs, liver and other organs. It doesn’t reverse the disease or repair any organ damage that has already happened.
- Bronchodilators may be prescribed to widen the airway and improve lung symptoms.
- Oxygen therapy and pulmonary rehabilitation may be required in some cases.
- Antibiotics are administered whenever there is any infection.
- Vaccinations against lung infections like pneumonia and annual flu shots are usually advised.