Pathology of COPD

Chronic obstructive pulmonary disease (COPD) is characterised
by poorly reversible airflow obstruction and an abnormal
inflammatory response in the lungs. The latter represents the
innate and adaptive immune responses to long term exposure
to noxious particles and gases, particularly cigarette smoke. All
cigarette smokers have some inflammation in their lungs, but
those who develop COPD have an enhanced or abnormal
response to inhaling toxic agents. This amplified response may
result in mucous hypersecretion (chronic bronchitis), tissue
destruction (emphysema), and disruption of normal repair and
defence mechanisms causing small airway inflammation and
fibrosis (bronchiolitis).
These pathological changes result in increased resistance to
airflow in the small conducting airways, increased compliance of
the lungs, air trapping, and progressive airflow obstruction—all
characteristic features of COPD.We have good understanding
of the cellular and molecular mechanisms underlying the
pathological changes found in COPD.