Chronic Inflammation Flashcards
Describe chronic inflammation
A prolonged inflammation with associated repair.
How does chronic inflammation arise?
- Takes over from acute inflammation. 2. Develops alongside acute inflammation. 3. Arises “de novo” (without preceding acute inflammation), e.g. autoimmune conditions.
Describe macrophage appearance and function.
A: Large cells, abundant with a foamy cytoplasm (phagolysosomes). F: Phagocytosis- antigen presentation to immune systems, inflammatory mediators- synthesis and release of many mediators, controls and regulates inflammatory response.
Describe lymphocyte appearance and function.
A: Small cells (slightly larger than RBCs), spherical nucleus. T Cell function: Varitety of types- Helper cells assist other inflammatory cells, cytotoxic cells destroy pathogens. B Cell function: mature into plasma cells, produces antibodies, neutralises pathogens.
Describe plasma cell appearance and function.
A: eccentric nucleus, ‘clock-face’ chromatin, peri-nuclear clearing. F: Fully differentiated B lymphocyte, produces antibodies.
Describe eosinophil appearance and function.
A: Bi-lobed nucleus, granular cytoplasm. F: release of a variety of mediators, hypersensitivity reactions & parasitic infections.
Describe giant cells.
They are big multinucleated cells. Fusion of multiple macrophages. There are three types of giant cell: Foreign body, Langerhans, Touton.
Where can the different giant cells be seen?
Langerhans giant cell can be seen in TB, touton giant cell can be seen in fat necrosis.
Effects of chronic inflammation.
Fibrosis, impaired function, atrophy, stimulation of immune response.
Describe Crohn’s disease.
Can affect all of GI tract, discontinuous patches of inflammation, inflammation affects full thickness of bowel wall, can sometimes find granulomata, less likely to have rectal bleeding.
Describe Ulcerative Colitis.
Affects large bowel only, continuous inflammation, inflammation affects superficial bowel wall only, no granulomata, more likely to have rectal bleeding.
Describe the types of granuloma.
Foreign body: destruction and removal of foreign material, few lymphocytes. Immune mediated: destruction and removal of pathogens, can be idiopathic, can undergo central necrosis, many lymphocytes.
