Send to

Choose Destination
Am J Respir Crit Care Med. 2012 Feb 1;185(3):246-59. doi: 10.1164/rccm.201108-1428CI. Epub 2011 Sep 29.

A review of α1-antitrypsin deficiency.

Author information

Cleveland Clinic Lerner School of Medicine, Cleveland Clinic Foundation, OH 44195, USA.


α(1)-Antitrypsin (AAT) deficiency is an underrecognized genetic condition that affects approximately 1 in 2,000 to 1 in 5,000 individuals and predisposes to liver disease and early-onset emphysema. AAT is mainly produced in the liver and functions to protect the lung against proteolytic damage (e.g., from neutrophil elastase). Among the approximately 120 variant alleles described to date, the Z allele is most commonly responsible for severe deficiency and disease. Z-type AAT molecules polymerize within the hepatocyte, precluding secretion into the blood and causing low serum AAT levels (∼ 3-7 μM with normal serum levels of 20-53 μM). A serum AAT level of 11 μM represents the protective threshold value below which the risk of emphysema is believed to increase. In addition to the usual treatments for emphysema, infusion of purified AAT from pooled human plasma-so-called "augmentation therapy"-represents a specific therapy for AAT deficiency and raises serum levels above the protective threshold. Although definitive evidence from randomized controlled trials of augmentation therapy is lacking and therapy is expensive, the available evidence suggests that this approach is safe and can slow the decline of lung function and emphysema progression. Promising novel therapies are under active investigation.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Atypon
Loading ...
Support Center