ACUTE INFLAMMATION

Jhia Anjela D. Rivera1,2

1 Department of Biology, College of Science, Polytechnic University of the Philippines2Department of Biological Sciences, School of Science and Technology, Centro Escolar University

ACUTE INFLAMMATION

• rapid in onset and of short duration

• characterized by fluid and plasma protein exudation and a predominantly neutrophilic leukocyte accumulation

• Has two major components:• Vascular Changes

• Cellular Events

STIMULI FOR ACUTE INFLAMMATION

• Infections (bacterial, viral, fungal, parasitic)

• Trauma (blunt and penetrating)

• Tissue necrosis (from any cause)

• Foreign bodies (splinters, dirt, sutures, crystal deposits)

• Immune Reactions (hypersensitivity reactions)

SEQUENCE OF EVENTS

1. Normal histology

2. Vasodilation

3. Increased vascular permeability

4. Leakage of exudate

5. Margination, rolling, adhesion

6. Transmigration (diapedesis)

7. Chemotaxis

8. PMN activation (Polymorphonuclear Neutrophils)

9. Phagocytosis: recognition, attachment, engulfment, killing (degradation or digestion)

10. Termination

11. 100% resolution, scar, or chronic inflammation

MORPHOLOGIC PATTERNS

• Serous Inflammation

-characterized by the outpouring of a watery, relatively protein-oor fluid (effusion) that, depending on the site of injury, derives either from the plasma or from the secretions of mesothelial cells lining the peritoneal, pleural, and pericardial cavities

MORPHOLOGIC PATTERNS

• Serous Inflammation

MORPHOLOGIC PATTERNS

• Serous Inflammation

MORPHOLOGIC PATTERNS

• Fibrinous Inflammation

-occurs as a consequence of more severe injuries, resulting in greater vascular permeability that allows large molecules (such as fibrinogen) to pass the endothelial barrier

MORPHOLOGIC PATTERNS

• Fibrinous Inflammation

MORPHOLOGIC PATTERNS

• Suppurative (purulent) inflammation and abscess formation -manifested by the collection of large amounts of purulent exudate (pus) consisting of neutrophils, necrotic cells, and edema fluid

• Abscesses are focal collections of pus that may be caused by seeding of pyogenic organisms into a tissue or by secondary infections of necrotic foci

MORPHOLOGIC PATTERNS• Suppurative (purulent) inflammation and abscess formation

MORPHOLOGIC PATTERNS

• Ulcer

- local defect, or excavation, of the surface of an organ or tissue that is produced by necrosis of cells and sloughing (shedding) of necrotic and inflammatory tissue

MORPHOLOGIC PATTERNS• Ulcer