Emphysema and α-1 Antitrypsin Deficiency

Abstract

I. Introduction Chronic obstructive pulmonary disease (COPD) is a highly prevalent disease affecting millions of individuals. Its estimated prevalence ranges from 7% to 19% worldwide. COPD has become the fourth-ranked cause of death in the United States, killing more than 100, 000 individuals each year. COPD is associated with impaired physical function, reduced quality of life, an increase in healthcare resource utilization, including frequent physician office visits and hospitalizations because of acute exacerbations, and chronic medical and oxygen therapy (1). Only 15% to 20% of smokers develop COPD, although the majority will develop some degree of airflow obstruction (2). Despite this, COPD remains underdiagnosed (3). Pathologic manifestations of COPD include small airway inflammation (bronchiolitis), lung parenchymal (alveolar) destruction, and loss of the pulmonary capillary bed. Physiologically, these lead to a loss of elastic recoil resulting in airflow limitation and hyperinflation leading to increased work of breathing and dyspnea. An important, underrecognized cause of emphysema is a-1 antitrypsin deficiency, an autosomal codominant disorder because of insufficient production or secretion of a-1 antitrypsin.