Pathology Lecture 2: Inflammation and Repair Flashcards
What are the forms of inflammation?
- Acute inflammation
2. Chronic inflammation
Define inflammation
Reaction of vascularized living tissue to cellular injury. Process removes necrotic debris and toxic compounds from injured area and destroyed infectious bacteria.
What are characteristics of acute inflammation?
- Rubor (redness)
- Tumor (swelling)
- Calor (heat)
- Dolor (pain)
- Functio laesa (loss of function)
What are two changes in vascular characteristics that occurs with acute inflammation?
- Increased vascular flow and caliber
2. Vascular permeability
What are the different inflammatory responses to tissue injury?
- Immediate transient response
- Immediate sustained response
- Delayed prolonged response
Define immediate transient response
Follows mild tissue injury. Immediately occurs 5-10 minutes after injury and lasts 15-30 minutes.
Define immediate sustained response
Follows more severe injury and accompanied by endothelial cell necrosis. Can last for several days and occurs with significant trauma, cellular injury, and infection.
Define delayed prolonged response
Initially delayed and may not occur until several hours or days after injury. Occur from burns, X-Ray damage, ultraviolet damage, bacterial toxins, or IV hypersensitivity.
What is leukocyte exudation on?
Collection of leukocytes, usually neutrophils, at infection site that phagocytosis bacteria and release debris causing further cellular injury.
What are chemical mediators of acute inflammation?
- Vasoactive amines
- Plasma proteases ie. complement, kinin, and clotting systems
- Arachidonic acids metabolites
When does chronic inflammation occur?
- After acute inflammation
- After repeated episodes of acute inflammation
- Low grade smoldering inflammatory process without acute inflammation
What are cellular constitutes and tissue changes for chronic inflammation?
- Macrophages, lymphocytes, plasma cells, eosinophils, fibroblasts
- Tissue destruction, vascular proliferation, fibrosis
What are three main steps in chronic inflammation development?
- Recruitment
- Local proliferation
- Survival and immobilization
What is chronic granulomatous inflammation?
Chronic inflammation characterized by area containing lymphocytes, plasma cells, macrophages, and multinucleated giant cells forming a granuloma.
Define caseating granuloma
Granulomatous process containing a central area of caseation necrosis with a peripheral rim of lymphocytes, macrophages, and langhans giant cells. Classically associated with TB or fungal infections
Define non-caseating granuloma
Granulomatous processes lacking central area of caseation necrosis. Includes: sarcoidosis, fungi, brucellosis, leprosy, foreign body reaction, cat scratch disease, syphilis, and parasites
What are systemic effects of inflammation?
- Fever
- Rigors
- Appetite suppression
- Sleep changes
- Protein degradation
- Hypotension
- Hematological effects
- Release of acute phase proteins
What are 3 categories of cellular regeneration cells, their definition, and examples?
- Labile cells: mitotically divide throughout life. Include epithelial, splenic, lymphoid, and hematopoietic cells
- Replicated under specific stimuli. Include parachymal, mesenchymal, and vascular endothelial cells
- Permanent cells: no division, scar tissue formed instead. Include neurons, skeletal muscle, and myocardium.
What is granulation tissue formation?
Formed by the regenerative process through which injured or necrotic tissue is gradually replaced and repaired. Not granulomatous inflammation.
What occurs with granulation tissue formation?
- Angiogenesis and neurovascularization
- Edema
- Fibroblast proliferation
- Collagenization
- Cellular components - increase in macrophages
Define collagen formation
Collagen fibers are laid down to increase strength and stability of repaired tissue. Granulation tissue initially contains type III collagen and is remodeled
What are non-collagen components?
- Elastin
- Laminin
- Proteoglycans
- Fibronectin
What are two types if wound healing?
- Primary union (first intention): clean wound with straight, easily approximated margins
- Secondary union (second intention): large gaping wounds with margins not readily approximated. Needs significant re-epithelialization repair.
What is wound dehiscence?
Opening of a partially healed wound
What are qualities affecting inflammatory/reparative process?
- Systemic influences: age, nutritional status, bleeding disorders, systemic disease (ie. diabetes), drugs
- Local influences: infection, adequacy of blood supply, foreign bodies, type of tissue
