Acute Inflammation Flashcards
Pathology
Acute Inflammation
Immediate and early response to injury, designed to deliver leukocytes to site of injury
Diverticulitis
Inflammation of
Diverticulosis
A disease or condition
Causes of Inflammation
- Microbial Infection
- Hypersensitivity reactions
- Physical agents (trauma, radiation, heat injury)
- chemicals (corrosives, acids, bacterial toxins)
- Tumour necrosis (Secondary to ischaemia)
What are hypersensitivity reactions?
Excessive immune response -> Tissue damage
Microbial Infection includes…
- Bacterial endotoxins
- Bacterial exotoxins
- Viral intracellular multiplication
- organisms causing hypersensitivity reactions
Bacterial exotoxins
chemicals released by bacteria which stimulate inflammation
Bacterial endotoxins
Associated with bacterial cell walls, also stimulate inflammation
Viral intracellular multiplication
leading to cell death, debris then stimulates inflammation
Cardinal signs of acute inflammation and why
- Redness (rubor)- due to dilation of vessels
- Heat (calor)- due to increased blood flow
- Swelling (tumor)- due to accumulation of fluid & increase in inflammatory cells migrating to the area
- Pain (dolor)- due to physical distortion of tissue & release of chemical mediators (Bk, PGs)
- Loss of function (functio laesa)
Stages of Inflammation
- Release of chemical mediators
- Vasodilation
- Increased vascular permeability
- Fluid accumulation
- Cellular recruitment
- Phagocytosis
Components of Acute Inflammation
- Vascular changes
-change in vessel calibre
-Increase in vascular permeability - Cellular events
-formation of cellular exudate
Vascular Changes in Acute Inflammation
- Changes in vascular calibre
- Initial transient constriction
- Then vasodilation (can last 15m to several hours)
Exudation
Formation of cellular exudate
Accumulation of neutrophil polymorphs