Alpha-1 antitrypsin (AAT) deficiency is condition passed down through families in which the liver does not make enough of a protein that protects the lungs and liver from damage. The condition can lead to emphysema and liver disease.
Alternative Names
AAT deficiency
Causes, incidence, and risk factors
Alpha-1 antitrypsin (AAT) is a type of protein called a "protease inhibitor." AAT normally works to protect the lungs from a naturally occuring destructive enzyme that is produced by the lungs in response to infections and toxins (such as cigarette smoke). Without enough AAT, these enzymes slowly destroy the lung tissue.
AAT deficiency is caused by a genetic defect that results in not enough AAT in the liver, lungs, and blood. Persons with this deficiency may also develop liver disease.
Studies show that AAT deficiency may be more common than once thought. Most adults with severe deficiency will develop emphysema, which often begins before age 40. Smoking can increase your risk. The condition is most common among Europeans and North Americans of European descent.
A physical examination may reveal a barrel-shaped chest. Listening to the chest with a stethoscope may reveal wheezing or decreased breath sounds. The following tests may also help with diagnosis:
Subcutaneous emphysema (1 image)(Doctor-Reviewed information)
Subcutaneous emphysema occurs when air gets into tissues under the skin covering the chest wall or neck.Subcutaneous emphysema can often be seen as a smooth bulging of the skin. When a health care provider feels(palpates) the skin, it produces an ...Reviewer: John E. Duldner, Jr., MD, MS, Assistant Professor of Emergency Medicine, Director of Research, Department of Emergency Medicine, Akron General Medical Center and Northeastern Ohio Universities College of Medicine. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.Date: 10/13/2008
Chronic obstructive pulmonary disease (7 images)
Average Rating:
(Doctor-Reviewed information)
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Smoking - tips on how to quit (2 images)(Doctor-Reviewed information)
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