A1AT

What is a Alpha-1 antitrypsin (A1AT) deficiency ?

Alpha-1 antitrypsin (A1AT) deficiency is a condition in which the body is incapable of making a protein that protects the lungs and liver from damage. The condition can lead to emphysema and liver disease.

About 10 percent of infants with alpha-1 antitrypsin deficiency develop liver disease, which often causes yellowing of the skin and whites of the eyes (jaundice). Approximately 15 percent of adults with alpha-1 antitrypsin deficiency develop liver damage (cirrhosis) due to the formation of scar tissue in the liver.

At first, many people who have AAT deficiency are diagnosed with asthma. This is because wheezing also is a symptom of asthma. Also, people who have AAT deficiency respond well to asthma medicines.

Signs and Symptoms

The first lung-related symptoms of alpha-1 antitrypsin deficiency may include shortness of breath, less ability to be physically active, and wheezing. These signs and symptoms most often begin between the ages of 20 and 40.Other signs and symptoms may include repeated lung infections, tiredness, a rapid heartbeat upon standing, vision problems, and weight loss. Some people who have severe AAT deficiency develop emphysema often when they're only in their forties or fifties. Signs and symptoms of emphysema include problems breathing, wheezing, and a chronic cough.

The other signs and symptoms most people experience with this deficiency are:

  • Chronic cough
  • Emphysema
  • COPD
  • Liver failure
  • Hepatitis
  • Hepatomegaly (enlarged liver)
  • Jaundice
  • Cirrhosis

Management

A1AT deficiency without symptoms

Where the diagnosis is made in the absence of symptoms there should be advice about not smoking and referral to a chest clinic for the assessment of possible occult disease. Many advise restraint with regard to alcohol consumption. However, one study suggests that neither alcohol nor viral hepatitis predisposes to advanced liver disease; however, two factors that do are obesity and being male.

Lung disease

Lung disease does not usually present until people are in their 30s and 40s. Smokers tend to develop symptoms around 10 years earlier than non-smokers. The symptoms are similar to COPD. The most common presentation is early-onset (when aged in 30s and 40s) emphysema, with the lung bases most affected. Lung cancer has also been reported but it is difficult to ascertain causal association due to other environmental factors.

Treatment and Diagnosis

Treatment of alpha-1 antitrypsin deficiency (AATD) depends on the symptoms and severity in each person. COPD and other related lung diseases are typically treated with standard therapy. Bronchodilators and inhaled steroids can help open the airways and make breathing easier.

Intravenous augmentation therapy (regular infusion of purified, human AAT to increase AAT concentrations) has been recommended for people with established fixed airflow obstruction (determined by a specific lung function test) This therapy raises the level of the AAT protein in the blood and lungs.

Lung transplantation may be an appropriate option for people with end-stage lung disease. Liver transplantation is the definitive treatment for advanced liver disease.