Alpha-1 Antitrypsin Deficiency: Whom to Test, Whom to Treat?

ABSTRACT

Alpha-1 antitrypsin deficiency (AATD) is the major identified genetic risk factor for chronic obstructive pulmonary disease (COPD). The biochemical events leading to lung destruction in AATD are well understood, and most of our understanding of the pathogenesis of COPD in general has been acquired through the study of AATD. There is a growing appreciation that early diagnosis of AATD can affect the course of disease and allow for appropriate treatment decisions to be made. Although there is published guidance regarding testing and treatment of AATD, the impact of this guidance has been minimal. AATD is underdiagnosed, and the evidence for current treatment recommendations is not without controversy. This article reviews the current recommendations for testing and treatment of AATD. Some of these recommendations are expected to change as legislation to prevent genetic discrimination is refined and new therapies for this relatively common genetic predisposition are developed. Additional genetic modifiers of COPD will be found, and the path set by AATD will facilitate their incorporation into our future management of COPD.

KEYWORDS

Alpha-1 antitrypsin deficiency - chronic obstructive pulmonary disease - emphysema - genetic testing - augmentation therapy

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