Alpha-1 Antitrypsin Deficiency

Overview

Alpha-1 antitrypsin deficiency is an inherited condition caused by the insufficient functioning of a protective protein produced in the liver. This protein normally acts as a shield, protecting the lungs from damage. When it is deficient, the lungs are left unprotected and gradually sustain damage. The liver can also be affected by this condition.

In a healthy person, the liver produces a protein called alpha-1 antitrypsin (AAT). This protein enters the bloodstream, travels to the lungs, and prevents harmful enzymes from destroying lung tissue. In AAT deficiency, this protective mechanism fails. Either not enough protein is produced, or the protein that is produced accumulates in the liver and cannot enter the bloodstream. As a result, the lungs sustain damage over time, and the protein that builds up in the liver can harm liver cells.

This condition affects millions of people worldwide but is most often diagnosed late. Many patients are followed for years with a diagnosis of COPD or asthma without anyone identifying the underlying genetic cause. Early diagnosis can make a meaningful difference in how the disease progresses.

Symptoms

The symptoms of AAT deficiency vary depending on which organ is affected. Lung symptoms are the most common. Symptoms generally begin to appear in a person's 30s or 40s and develop much earlier and more severely in people who smoke.

• Lung symptoms. Shortness of breath is the most common symptom. It initially appears only during exertion and gradually becomes noticeable with lighter activity as well. Chronic cough, increased phlegm particularly in the mornings, recurrent lung infections, and wheezing are other frequently seen symptoms. These closely resemble COPD or asthma, which is why diagnosis is often delayed.
• Liver symptoms. In newborns, prolonged jaundice may be the first sign. In children, poor growth and abdominal swelling can occur. In adults, fatigue, discomfort in the upper right abdomen, and elevated liver enzymes may develop. In advanced stages, cirrhosis and liver failure can occur. In some people, only the liver is affected, with no lung symptoms at all.
• No symptoms at all. In some people, the condition causes no symptoms for many years and is only discovered through family screening or routine blood tests.

When to See a Doctor

See a doctor in the following situations:

• If you have been diagnosed with COPD or emphysema before the age of 40 — especially if you do not smoke or smoke very little — an underlying cause should be investigated.
• If there is a family history of lung or liver disease at a young age, screening is recommended.
• If you have unexplained chronic shortness of breath, recurrent lung infections, or elevated liver enzymes, see a doctor.
• If prolonged jaundice or liver enlargement is detected in a newborn, a medical evaluation may be needed.

Causes

AAT deficiency is an inherited condition. The genes passed down from both parents determine how much AAT protein is produced and how it functions. The condition presents in its most severe form when a faulty gene is inherited from both parents. People who inherit a faulty gene from only one parent are generally carriers and may not develop clinical symptoms, but they can pass the gene on to their children.

The severity of the condition varies greatly from person to person. In some people, very little protein is produced and serious lung and liver disease develops. In others, protein levels are less affected and no symptoms may appear.

Genetic predisposition is necessary for the condition to develop, but environmental factors largely determine how it progresses. Smoking dramatically accelerates lung damage. Exposure to dust, fumes, and air pollution also causes the lungs to deteriorate more rapidly. Alcohol accelerates liver damage.

Diagnosis

AAT deficiency is frequently diagnosed late. Because its symptoms overlap with those of much more common conditions such as COPD or asthma, specific tests are needed to reach the correct diagnosis.

• Blood test. This is the first step in the diagnostic process. The level of AAT protein in the blood is measured. A low level points to a deficiency.
• Genetic test. If a low level is detected on the blood test, a genetic test is performed to identify which gene change is present. This test is important for understanding the severity of the condition and the risk to family members.
• Lung function tests. These are performed to assess the extent of lung damage. Breathing tests show how much the lungs have been affected and are used in planning treatment.
• Lung imaging. A chest X-ray or CT scan visualizes damage in the lungs. The damage caused by AAT deficiency has a characteristic pattern that can contribute to the diagnosis.
• Liver assessment. Liver enzymes and ultrasound are used to evaluate liver damage. A liver biopsy may be performed when necessary.
• Family screening. First-degree relatives of every newly diagnosed patient should be screened. Siblings and children are at particular risk.

Treatment

Treatment of AAT deficiency is aimed at two main goals: slowing the progression of damage and bringing symptoms under control.

• Augmentation therapy. This is a specific treatment for patients with lung involvement. AAT protein obtained from donors is administered intravenously once a week. The aim is to raise AAT levels in the blood and slow further damage to lung tissue. It does not reverse existing damage — it slows the progression of the disease.
• Quitting smoking. For people with AAT deficiency, this is unquestionably the most important step. Smoking dramatically accelerates lung damage. Quitting is the single most powerful intervention for improving the course of the disease.
• Treatment of lung symptoms. In patients with lung involvement, standard COPD treatment is applied. Bronchodilators (medications that open the airways), oxygen therapy when needed, and pulmonary rehabilitation programs are used.
• Managing liver disease. In patients with liver involvement, alcohol must be stopped entirely. Hepatitis A and B vaccinations are recommended. In advanced liver failure, liver transplantation may be considered.
• Protection from infections. Lung infections can cause rapid deterioration in patients with AAT deficiency. Annual flu vaccination and pneumococcal vaccination are recommended for all patients.
• Genetic counseling. Patients and their families can benefit from genetic counseling. The risk of passing the condition on within the family and the screening of family members are addressed during this process.

Living with AAT Deficiency

AAT deficiency is a chronic condition. With the right treatment and lifestyle adjustments, however, many patients can live long and fulfilling lives.

• Stay away from smoking entirely. In patients who do not smoke, lung disease progresses much more slowly and may not develop at all in some people. Not smoking is the single most critical decision a person with this condition can make.
• Pay attention to air quality. Dust, fumes, and chemical vapors increase lung damage. If there is occupational exposure, protective measures should be taken. On days with high air pollution, strenuous outdoor activity should be avoided.
• Exercise regularly. Activities such as walking, swimming, and cycling help preserve lung capacity. Pulmonary rehabilitation programs provide professional guidance.
• Keep up with vaccinations. Annual flu vaccination and pneumococcal vaccination are very important for protection against lung infections.
• Limit or stop alcohol entirely. In patients with liver involvement, alcohol must be stopped completely.
• Attend regular follow-up appointments. Lung function tests and liver assessments should not be missed. Regular monitoring is essential for tracking the course of the disease and adjusting treatment in a timely way.

Preparing for Your Appointment

What you can do:

• Note when symptoms such as shortness of breath, cough, or fatigue began.
• Share your smoking history.
• Mention any family history of lung or liver disease at a young age.
• Share any occupational or environmental exposure to dust or fumes.
• List all medications you are taking.
• Bring any previous lung function test or blood test results if available.
• Write your questions down in advance.

Questions you can ask your doctor:

• How much have my lungs or liver been affected?
• Do I need augmentation therapy?
• Can I get support to quit smoking?
• Should my family be screened?
• Which vaccinations should I get?
• How often do I need to be monitored?

Your doctor may ask you:

• When did the symptoms begin and how have they progressed?
• Do you smoke or have you smoked in the past?
• Is there a family history of lung or liver disease?
• Are you exposed to dust or chemicals at work?
• Have you previously been diagnosed with COPD or asthma?
• Do you drink alcohol?