GTR Home > Conditions/Phenotypes > Alpha-1-antitrypsin deficiency


Alpha-1 antitrypsin deficiency (AATD) is characterized by an increased risk for: chronic obstructive pulmonary disease (i.e., emphysema, persistent airflow obstruction, and/or chronic bronchitis) in adults; liver disease in children and adults; panniculitis ; and c-ANCA positive vasculitis. Emphysema, sometimes with associated bronchiectasis, is the most common manifestation of AATD. Smoking is the major factor influencing the course of chronic obstructive pulmonary disease (COPD). The onset of respiratory disease in smokers with AATD is characteristically between ages 40 and 50 years; in non-smokers, the onset can be delayed to the sixth decade, and some non-smokers never develop COPD. Non-smokers may have a normal life span. Although reported, emphysema in children with AATD is extremely rare. AATD-associated liver disease, which is present in only a small portion of affected children, manifests as obstructive jaundice and increased serum aminotransferase levels in the early days and months of life. The incidence of liver disease increases with age. Liver disease in adults (manifesting as cirrhosis and fibrosis) may occur in the absence of a history of neonatal or childhood liver disease. The risk for hepatocellular carcinoma (HCC) is increased in individuals with AATD. [from GeneReviews]

Associated genes

  • Also known as: A1A, A1AT, AAT, PI, PI1, PRO2275, alpha1AT, SERPINA1
    Summary: serpin peptidase inhibitor, clade A (alpha-1 antiproteinase, antitrypsin), member 1

Clinical features


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Practice guidelines

  • Orphanet, 2010
    Orphanet, Alpha-1 antitrypsin deficiency, 2010
  • ATS/ERS, 2003
    [American Thoracic Society/European Respiratory Society Statement: Standards for the diagnosis and management of individuals with alpha-1 antitrypsin deficiency].
  • EuroGentest, 2011
    Clinical utility gene card for: α-1-antitrypsin deficiency

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