Chronic Inflammation Flashcards
Outcomes of acute inflammation, chronic inflammation, wound healing and repair
What are the four outcomes of acute inflammation?
- Complete resolution
- Suppuration/abscess formation
- Healing by fibrosis/organization
- Chronic inflammation
Define chronic inflammation
Inflammation lasting weeks or months in which active inflammation, tissue destruction, and attempts at healing are proceeding simultaneously
Can chronic inflammation arise without a pre-existing acute inflammatory component?
Yes
What are three examples of chronic inflammation that occur without a pre-existing acute inflammatory component?
- Persistent microbial infection
- Prolonged exposure to exogenous or endogenous toxic agents
- Autoimmune diseases
Within the context of chronic inflammation, macrophages change leading to…
- Long-lived tissue macrophages
- Epithelioid cells
- Multinucleated giant cells
What is the predominant cell in granulomatous inflammation?
The activated macrophage (possesses a modified epithelial-like (epithelioid) appearance)
What are four features of granulomatous inflammation?
- Multinucleated giant cells
- Lymphocytes
- Necrosis
- Fibroblasts
What is a granuloma?
A focal area of granulomatous inflammation; a central zone of necrosis surrounded by microscopic aggregates of epithelioid cells, lymphocytes, and fibroblasts
What are some general causes of granuloma?
- Immune reaction
- Chronic irritation
- Undigestible foreign material
- Unknown etiologies
What are some specific causes of granuloma?
- Tuberculosis
- Leprosy
- Syphilis
- Sarcoidosis
- Fungal infection
- Suture
What are four morphologic patterns in acute and chronic inflammation?
- Serous inflammation
- Fibrinous inflammation
- Suppurative inflammation
- Ulceration; decubitus ulcers
Repair process involves:
- Total reconstruction (regeneration/resolution)
- Partial reconstruction
- Universal repair tissue: fibrous connective tissue scar
What are the four components of wound healing and repair?
- Angiogenesis: migration and proliferation of endothelial cells
- Migration and proliferation of fibroblasts
- Deposition of extracellular matrix
- Remodeling of connective tissue
What is the hallmark tissue of early healing by fibrosis?
Granulation tissue
Granulation tissue is composed of what four components?
- Proliferating small capillaries
- Proliferating fibroblasts/myofibroblasts
- Extracellular fluid
- Macrophages
What are the four functions of granulation tissue?
- Fill in tissue “gaps”
- Remove dead cell debris
- Aid in wound contraction
- Form an early “pre-scar”
What are the steps of healing by primary union/intention in order?
- Blood clot fills incisional space
- Neutrophil infiltration
- Epithelial continuity restored
- Macrophage infiltration
- Granulation tissue fills space
- Progressive collagenization
- Remodeling
What is secondary union/intention compared to primary intention?
- Large amounts of granulation tissue are required
- Inflammatory reaction is more prolonged
- More debris and inflammatory exudate
- More pronounced scar formation
What factors influence local wound healing?
- Type, size, and location
- Vascular supply
- Infection
- Movement
What factors influence systemic wound healing?
- Circulatory status
- Infection
- Malnutrition
complications of normal wound healing
What is proud flesh?
Excessive granulation tissue
complications of normal wound healing
What is keloid formation?
Hypertrophic scar: excessive collagen deposition
complications of normal wound healing
What is wound dehiscence?
Mechanical stress
complications of normal wound healing
What is contracture?
Excessive wound contraction
List four complications of normal wound healing
- Proud flesh
- Keloid formation
- Wound dehiscence
- Contracture
