Emphysema

Source:  Emphysema    Tag:  hyperhomocysteinemia definition
Emphysema is defined as an abnormal, permanent dilatation of the airways distal to the terminal bronchioles due to a destruction in the walls.
There are 4 types of emphysema:
1) centriacinar/centrilobular - seen in cigarette smokers
2) panacinar/panlobular - seen in α1-antitrypsin deficiency
3) distal acinar
4) irregular.
Pathogenesis:
Protease- antiprotease imbalance theory as shown in the picture above.

On examination:
Patient will be dyspneic, hyperventilating and have a prolonged expiration. The chest will be barrel shaped.