Flashcards in Acute Inflammation 3 Deck (17)
What are the four possible outcomes of acute inflammation?
1. Resolution - return to normal function
2. Pus formation (abscess)
3. Chronic inflammation
How is acute inflammation resolved?
1. Blood vessels return to normal permeability
2. Fluid and proteins drain into lymph node
3. Pinocytosis (ingestion of liquid) into macrophages
4. Phagocytosis of apoptotic neutrophils
5. Phagocytosis of necrotic debris
6. Disposal of macrophages
What characterises purulent inflammation?
Large amounts of dead white cells and bacteria (pus), as well as neutrophils, necrotic cells and edema fluid
What is an abscess?
A collection of purulent inflammatory tissue in a confined space or deep within tissues. There's a central region of necrotic cells, and fibroblast proliferation - fibroblasts are evidence of the battle between inflammation and repair. There may be a fibrotic wall
How does fibrosis occur?
Fibrinous inflammation comes from severe injury that damages the integrity of blood vessels.
Fibrogen enters the tissue, is cleaved to make fibrin, which can be broken down and removed. If not removed, can lead to the scarring characteristic of fibrosis. Loss of function can occur as fibrin is not flexible.
What is serous inflammation?
Thin fluid from plasma or mesothelial cells accumulates in the serous membrane that forms the lining of the abdomen and coelomic cavities (peritoneal). Not a lot of cellular involvement
Describe chronic inflammation?
Inflammation of prolonged duration, in which active inflammation, tissue destruction and repair proceed simultaneously.
Can be endogenous, where acute inflammation doesn't resolve, or exogenous, as a result of a persistent infection.
How are the cell populations of acute vs chronic inflammation different?
Acute: neutrophils, monocytes/macrophages
Chronic: macrophages, T cells, plasma cells, fibroblasts
How do the initiators of acute and chronic inflam. differ?
Acute: microbial surfaces/fragments, injured tissues/tissue fragments
Chronic: non-digestible organisms, non-degradable foreign matter & auto-immune reactions
Which molecules activate monocytes into macrophages?
Cytokines (IFN-y), endotoxins, and non-immune chemical mediators
How to B cells, T cells and macrophages get into tissues?
They move from to the blood to the tissues via adhesion proteins
In which granulocyte is Major Basic Protein found?
What is a granuloma, and in which disease do you see a colonic granuloma?
A focus of chronic inflammation containing transformed, aggregated and epithelioid macrophages, surrounded by a collar of leukocytes
Colonic granulomas are seen in crohn's disease
What are giant cells?
Fused epithelioid cells, found in periphery of some granulomas. They have a large cytoplasmic mass, with 20 or more small nuclei
What are some disease with granulomas?
TB, leprosy, syphillis
What is fibrosis?
The laying down of fibrous scar tissue far outside the original infection parameters, which can lead to loss of function. Tissue destruction is also a feature