Alpha-1 antitrypsin deficiency

A deficiency of a protein produced in the liver that blocks the destructive effects of certain enzymes. The condition may lead to emphysema and liver disease .

Alternative Names

AAT deficiency

Causes, incidence, and risk factors

Alpha-1 antitrypsin deficiency results from a genetic defect. The mechanism that causes associated liver disease and emphysema in some people with this deficiency is not known, however some evidence suggests that it may be related to inflammation. Approximately 75% of adults with severe deficiency will develop emphysema, which often begins before 40 years of age. Smoking can increase risk.

Signs and tests

  • Physical examination
  • may reveal a barrel-shaped chest. Listening to the chest with a stethoscope (
  • auscultation ) may reveal wheezing , crackles, and/or decreased breath sounds. The following tests may also help diagnosis:
  • arterial blood gases
  • serum
  • alpha-1 antitrypsin level
  • chest X-ray
  • pulmonary function
  • test
  • Treatment

    Replacement (or "augmentation") therapy with the missing AAT protein is available, however, it is not known how effective this is once disease has developed or which people would benefit most. Certainly, smoking avoidance or cessation is crucial. Other treatments include bronchodilators and prompt antibiotics for upper respiratory tract infections.

    Expectations (prognosis)

    Some people with this deficiency will not develop liver or lung disease . Emphysema and cirrhosis , however, are both progressive diseases which can kill.


  • emphysema
  • cirrhosis
  • Calling your health care provider

  • Call your health care provider if you have symptoms like those listed above.
  • Prevention

    There is no known prevention for this genetic defect.

    Treatment Options – Sorted by Soonest Available


    Save up to versus Emergency Room Visit

    Find Nearest Urgent Care

    Please enter Zip Code for nearest facility

    Av. Wait Time: 3 Min.


    Find Nearest ER

    Please enter Zip Code for nearest facility

    Av. Wait Time: 1 - 8 Hrs.


    Find Nearest Primary Care

    Please enter Zip Code for nearest facility

    Av. Wait Time: 1 - 10 Days

    News related to "Alpha-1 antitrypsin deficiency"