INFLAMMATION

Inflammation

Inflammation is a protective response of the body to injury or infection, characterized by redness, warmth, swelling, and pain. It involves the activation of immune cells, the release of chemical mediators, and the changes in blood flow and tissue structure.

Key Points:

• Pathway: → Injury or infection → Release of chemical mediators (histamine, bradykinin, cytokines) → Activation of immune cells (neutrophils, macrophages)

• Types:

  • Acute inflammation: Immediate response to injury or infection, characterized by increased blood flow and permeability.
  • Chronic inflammation: Prolonged response to injury or infection, characterized by persistent immune cell infiltration and tissue damage.

• Signs:

  • Redness
  • Warmth
  • Swelling
  • Pain
  • Loss of function

• Mechanisms: → Vasoconstriction → Increased capillary permeability → Exudation of fluid and cells → Chemotaxis of immune cells

• Immune Cells:

  • Neutrophils: First line of defense, involved in phagocytosis and killing of microorganisms.
  • Macrophages: Involved in phagocytosis, antigen presentation, and secretion of chemical mediators.
  • Lymphocytes: Involved in adaptive immunity, including T cells and B cells.

• Chemical Mediators:

  • Histamine: Released by mast cells, responsible for vasodilation and increased capillary permeability.
  • Bradykinin: Released by kininogen, responsible for vasodilation and increased capillary permeability.
  • Cytokines: Released by immune cells, responsible for chemotaxis, inflammation, and tissue damage.

• Treatment:

  • Rest and relaxation
  • Ice or cold compresses
  • Compression bandages
  • Elevation of affected area
  • Anti-inflammatory medications (NSAIDs, corticosteroids)

Inflammation - Acute and Chronic Inflammation

Acute Inflammation

• Acute inflammation is a short-term response to injury or infection.
• It is characterized by redness, heat, swelling, pain, and loss of function.
• White blood cells are present in the affected tissue.
• The primary goal of acute inflammation is to eliminate the cause of the injury or infection.

Pathway of Acute Inflammation

1. → Injury or infection → Chemical signals released → Vasodilation and increased permeability of blood vessels → White blood cells migrate to the affected area → Phagocytosis and removal of foreign particles and pathogens

Types of Acute Inflammation

• Suppurative inflammation: characterized by the presence of pus.
• Catarrhal inflammation: characterized by increased mucus production.
• Fibrinous inflammation: characterized by the deposition of fibrin.
• Diphtheric inflammation: characterized by the formation of a membrane.

Chronic Inflammation

• Chronic inflammation is a long-term response to injury or infection.
• It is characterized by the presence of lymphocytes and plasma cells.
• The primary goal of chronic inflammation is to eliminate the cause of the injury or infection and restore tissue function.

Types of Chronic Inflammation

• Granulomatous inflammation: characterized by the formation of granulomas.
• Atrophic inflammation: characterized by tissue atrophy.
• Fibrinous inflammation: characterized by the deposition of fibrin.
• Dystrophic inflammation: characterized by the deposition of collagen.

Pathway of Chronic Inflammation

1. → Injury or infection → Chronic inflammation → Lymphocytes and plasma cells present → Cytokines released → Fibrosis and tissue remodeling → Restoration of tissue function

Differences between Acute and Chronic Inflammation

• Duration: acute inflammation is short-term, while chronic inflammation is long-term.
• White blood cells: acute inflammation is characterized by the presence of white blood cells, while chronic inflammation is characterized by the presence of lymphocytes and plasma cells.
• Goal: the primary goal of acute inflammation is to eliminate the cause of the injury or infection, while the primary goal of chronic inflammation is to eliminate the cause of the injury or infection and restore tissue function.