Chronic obstructive pulmonary disease pathophysiology
|
Chronic obstructive pulmonary disease Microchapters |
|
Differentiating Chronic obstructive pulmonary disease from other Diseases |
|---|
|
Diagnosis |
|
Treatment |
|
Case Studies |
|
Chronic obstructive pulmonary disease pathophysiology On the Web |
|
American Roentgen Ray Society Images of Chronic obstructive pulmonary disease pathophysiology |
|
FDA on Chronic obstructive pulmonary disease pathophysiology |
|
CDC on Chronic obstructive pulmonary disease pathophysiology |
|
Chronic obstructive pulmonary disease pathophysiology in the news |
|
Blogs on Chronic obstructive pulmonary disease pathophysiology |
|
Directions to Hospitals Treating Chronic obstructive pulmonary disease |
|
Risk calculators and risk factors for Chronic obstructive pulmonary disease pathophysiology |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Philip Marcus, M.D., M.P.H. [2]; Associate Editor(s)-In-Chief: Cafer Zorkun, M.D., Ph.D. [3]
Overview
Chronic obstructive pulmonary disease is a group of diseases characterized by the pathological limitation of airflow in the airway that is not fully reversible.
Pathophysiology
Chronic obstructive pulmonary disease is a blanket term with two main underlying causations the influence the pathophysiologic outcome: chronic bronchitis and emphysema.
Chronic bronchitis
Chronic bronchitis is defined in clinical terms as a cough with sputum production on most days for 3 months of a year, for 2 consecutive years.[1]
Chronic bronchitis is hallmarked by hyperplasia (increased number) and hypertrophy (increased size) of the goblet cells (mucous gland) of the airway, resulting in an increase in secretion of mucus which contributes to the airway obstruction. Microscopically there is infiltration of the airway walls with inflammatory cells, particularly neutrophils. Inflammation is followed by scarring and remodeling that thickens the walls resulting in narrowing of the small airway. Further progression leads to metaplasia (abnormal change in the tissue) and fibrosis (further thickening and scarring) of the lower airway. The consequence of these changes is a limitation of airflow.[2].
Emphysema
Emphysema is defined histologically as the enlargement of the air spaces distal to the terminal bronchioles, with destruction of their walls.
The enlarged air sacs (alveoli) of the lungs reduces the surface area available for the movement of gases during respiration. This ultimately leads to dyspnea in severe cases. The exact mechanism for the development of emphysema is not understood, although it is known to be linked with smoking and age.
References
- ↑ Longmore M, Wilkinson I, Rajagopalan S (2005). Oxford Handbook of Clinical Medicine, 6ed. Oxford University Press. pp 188-189. ISBN 0-19-852558-3.
- ↑ Kumar P, Clark M (2005). Clinical Medicine, 6ed. Elsevier Saunders. pp 900-901. ISBN 0702027634.