Enzymes are proteins that are responsible for all of the chemical interactions that occur within the body. Enzyme inhibitors control the proper function of these enzymes or proteins. When enzymes inhibitors are absent or have not developed properly, some bodily functions cannot occur. Alpha 1 antitrypsin is an enzyme inhibitor which is directly responsible for protection of the lungs from toxins, so its absence or deficiency results in lung damage and development of chronic pulmonary obstructive disorder (COPD), including emphysema and bronchitis.

Alpha 1 antitrypsin deficiency affects the liver in a different way – abnormal alpha 1 antitrypsin proteins become trapped within the liver and cause damage over time. AATD is a genetic or inherited disease (from both parents) and is commonly diagnosed in persons over 50, though symptoms may be displayed in children.

Typical symptoms
Symptoms are typical of other liver disease or damage and include fatigue, jaundice, and ascites (abdominal distention due to fluid). The shape and appearance of the liver will likely be affected. Lung symptoms might be breathlessness, breathing difficulty, emphysema and COPD. A rarer symptom of AATD is a painful skin disorder called palliculitis.

Diagnosis
As it is an inherited condition, genetic blood testing might be undertaken. This would occur following liver blood enzyme analyses, scanning techniques and a liver biopsy (the removal of a sample of liver tissue for microscopic examination).

Incidence
AATD is not uncommon and typically affects one person in 1,500 to 3,500 with European ancestry but is rare in Asian populations. However, numbers might be underestimated as it is often undiagnosed or misdiagnosed as asthma.

Treatment
Management and prevention of lung and liver damage are treatment aims as there is no known cure for AATD. Management of symptoms as they arise, monitoring disease progression and reducing further risk of organ damage are all important. Recommended lifestyle changes might include maintaining a healthy weight and diet, and the avoidance of alcohol and smoking. On occasion, if liver damage is so severe, a liver transplant might be undertaken.

Prognosis
The prognosis of individuals with AATD varies enormously from person to person. Many people will have normal life expectancies, while others may develop life-threatening complications. In addition, those with AATD might be more susceptible to developing a liver cancer called hepatocellular carcinoma or HCC.