Pathologic Principles

It is extremely important to have a good understanding of Pathological processes that occur if one desires to pick them up by physical exam. Each organ or tissue responds in only certain ways for offending agents. Same type of pathological responses are often seen with different etiologies.

The Lungs - Diffuse


This is a space occupying lesion. There is no lung architecture. The cut surface is homogenous. Margins are sharp. The lesion may not respect fissures. The lesion can infiltrate invade or compress surrounding structures.
Cavity is a hole in the lung. It has wall which can be made up of necrotic tumor or inflammatory mass. The lumen may be irregular. it can be either empty or filled with pus, blood, necrotic debris, or fungus ball. The cavity can be completely filled. There may or may not be a communication to bronchus.
The lung is focally fibrotic. There is loss of lung volume.
The bases of lungs are congested and heavy.
In patients with COPD, Asthma and Emphysema the alveoli are dilated or distended. The lungs are larger either due to loss of elastic recoil as in emphysema or due to air trapping as in Asthma. There may be blebs in Emphysema. Most of these blebs are superficial and along the upper lobes.




Chest Wall