Antitrypsin Deficiency and Abnormal Protease Inhibitor Phenotypes

Abstract

Protease inhibitor phenotypes associated with severe and intermediate antitrypsin deficiency were observed more frequently than expected in 164 patients with chronic, obstructive lung disease. The risk associated with any phenotype appears related to the severity of the deficiency. An association between the intermediate deficiency and chronic, obstructive lung disease would have been obscured if only the serum concentration of antitrypsin had been measured. When compared with patients with normal protease inhibitor types, those with the intermediate deficiency generally developed overt disease after relativeîy little exposure to cigarette smoke. It is suggested that antitrypsin deficiency is one inherited abnormality that is predisposing to the development of lung disease by rendering individuals more susceptible to the harmful effects of environmental factors, in this circumstance, lung disease in these individuals is preventable.