Chronic Inflammation Flashcards
Name the factors that favour quick recovery of the body
Minimal cell death and tissue damage, the occurrence in an organ or tissue that is able to regenerate, rapid destruction of the casual agent (the cause of the inflammation) and removal of fluid and debris by vascular drainage
What is organisation?
The replacement of destroyed tissue by granulation tissue
what is granulation tissue?
The new connective tissue that forms on the surface of a wound during the wound healing process.
What factors cause organisation to occur?
Large amounts of fibrin, substantial necrosis tissue and exudate and debris that cannot be removed or discharged.
What occurs during organisation?
Most of the skin is completely destroyed while the underlying tissue undergoes repairs. The damaged area is replaced by vasular granulation tissue, that is why it appears red in colour.
What is inflammatory exudate replaced by and regulated by?
replaced by capillaries, macrophages, fibroblasts and collagen. It is regulated by growth factors; TNF (Tumor necrosis factor which is secreted by inflammatory cells) , EGF (epidermal growth factor) and FGF (fibroblast growth cell)
How can chronic inflammation arise?
It can arise primarily so without acute inflammation first. It can be a progression from acute inflammation and can arise from recurrent episodes of acute.
Name 6 examples of primary chronic inflammation
- Resistance of infectious agents to phagocytoisis and intracellular killing. e.g. tuberculosis, leprosy and viral infections.
- Foreign body reactions to endogenous materials e.g. gout
- Foreign body reactions to exogenous materials e.g. asbestos
- Some autoimmune diseases such as rheumatoid arthritis.
- Specific diseases of unknown cause
- Primary granulomatous diseases (accumulation of inflammatory cells) e.g. sarcoidosis.
what are endogenous materials?
Materials that originate from within a cell.
Name some factors that favour the progression of acute to chronic
Indigestible materials like glass or suture material. Deep seated supperative inflammation where drainage is delayed or inadequate (due too thick abscess walls, fibrous/granulation tissue, organised pus and fibrous scars.) recurrent episodes of acute inflammation.
Name some symptoms of chronic inflammation
Chronic ulcers (mucosa breached, base lined with granulation tissue and fibrous tissue in layers on muscle for peptic uclers)
Chronic abscess in cavities (osteomyelitis)
Fibrosis, thickening of the walls in hollow organs and granulomatous inflammation.
Name the cells of chronic inflammation and how this differes from acute
The cells which predominate chronic are lymphocytes, macrophages and plasma cells. Whereas in acute, neutrophils predominate.
Name some of the features of macrophages
They can phagocytic abilities, can harbour organisms that are resistant to lysosomal enzymes meaning certain organelles can hide in macrophages. They produce a range of important cytokines and are activated by Macrophage activation factor (MAF) and Migration inhibitor factor (MIF)
What is a granuloma?
A mass of epithelioid histocytes (macrophage in connective tissue)
What is the function of a granuloma?
It has a secretory function but little phagocytic activity.
