Hereditary deficiency of a blood component, Alpha 1 Protease inhibitor, also called as Alpha 1 Antitrypsin (AAT) can cause familial (runs in family) emphysema. Emphysema (progressive form of COPD) is a condition in which there is over-inflation of air sacs (alveoli) in the lungs.
Alpha 1 Antitrypsin is a protein made by the liver. This protein inhibits an enzyme called neutrophil elastase (released by white blood cells in the body). But when there is not enough Alpha-1 Antitrypsin, neutrophil elastase destroys the lung tissue. This enzyme causes breakdown of elastin (protein) in the alveolar walls (alveoli are air sacs present in the lungs). As a result the alveoli lose their elasticity and are therefore unable to completely deflate and fill with fresh air for adequate ventilation. This affects the exchange of oxygen and carbon dioxide in the lungs, causing shortness of breath.
It has also been observed that cigarette smoking can further worsen the lung damage in such patients. The irritating and toxic effects of cigarette smoke stimulates the white blood cells to migrate to the lungs which in turn causes increased release of elastase. Cigarette smoke is also known to inhibit the activity of Alpha1 Antitrypsin. According to NHLBI patients with Alpha-1 Antitrypsin can take certain precautions to protect the lungs. These include:
- Vaccination for flu and pneumonia
- Taking early treatment for lung infection
- Giving up smoking
- Taking regular medications and oxygen therapy (if required)
- Learning breathing techniques (pulmonary rehabilitation)
Many researches are still being conducted to learn more about Alpha-1Antitrypsin deficiency and for new treatments. Scientists feel that gene therapy maybe a solution to this inherited deficiency.