Pulmonary Physiology of Chronic Obstructive Pulmonary Disease, Cystic Fibrosis, and Alpha-1 Antitrypsin Deficiency.

Cystic fibrosis is predominantly an airway disease with marked bronchiectatic changes associated with inflammation, chronic colonization, and progressive airflow obstruction. The condition can be identified in childhood and monitored with detectable airway changes early in life while conventional spirometry remains in the normal range. Alpha-1 antitrypsin deficiency can also be detected early in life through blood spot and genetic testing and leads (in some) to the development of airflow obstruction and a predominant emphysema phenotype with bronchiectatic changes in about 30%. Early detection also allows the natural history of the pulmonary physiological changes to be determined. Chronic obstructive pulmonary disease is usually detected late in the disease process when significant damage has occurred. The condition consists of varying combinations of airway disease, bronchiectasis, colonization, and emphysema. Lessons learned from the physiological evolution of airway disease in cystic fibrosis and the emphysema of alpha-1 antitrypsin deficiency provide strategies to enable early detection of chronic obstructive pulmonary disease in general and its phenotypes.