General Pathology

An Introduction to General Pathology

• The term pathology is derived from:
  • Pathos, or suffering
  • Logos, or reasoning/logic.
• Pathology is defined as the study of disease including:
  • Aetiology - causal factor(s)
  • Pathogenesis - the development of the disease within the body.
  • Lesions - the observable structural changes in the tissues and fluids of the body.
  • Pathophysiology - the functional changes in diseased tissues.
  • Sequel - the consequences of the disease in the body.
  • Remote effects - the effect of disease in one tissue on other tissues in the body.

Lesions

• Lesions are the abnormalities or changes seen in living tissues due to disease.
• Observed in
  • The live animal
  • Tissues surgically removed from the live animal
    • Biopsy/ excision
  • Animals soon after death
    • Necropsy, post-mortem examination.

Decription of Lesions

• Descriptions of lesions is very important
• Whole organs, tissues or individual lesions are described under headings such as
  1. Size
  2. Shape
  3. Colour
  4. Weight - generally referred to body weight
  5. Texture and Consistency
  6. Appearance of the cut surface
  7. Contents of hollow organs
  8. Position, relationships and effects on adjacent tissues