Define chronic inflammation.
- prolonged inflammation with associated repair.
- delayed onset, variable duration and appearance, limits damage and initiates repair and can cause debilitating symptoms as result.
how does chronic inflammation arise?
- takes over from acute inflammation.
- alongside acute as severe or persistent irritation.
- ” de novo “
differentiate between a monocyte and a macrophage.
a monocyte is a WBC found in circulation and a macrophage or histiocyte in a monocyte that entered the tissue space.
describe the appearance of a macrophage.
- larger than a RBC, abundant in cytoplasm that contains foamy collections of phagolysosymes.
- ‘slipper shaped nucleus’
what is the function of a macrophage?
- primarily the removal of pathogens, necrosis and debris and presenting of antigens to immune system.
- synthesis and release of inflammatory mediators, that control and regulate inflammation.
describe the appearance of a lymphocyte.
- slightly larger than RBC, large central and spherical nucleus and thin rim of cytoplasm.
what is the function of a lymphocyte?
- T and B lymphocytes.
- T cells are either helper cells assisting other inflammatory cells pr cytotoxic that destroy pathogens.
- B cells mature into plasma cells that produce antibodies and neutralises pathogens.
describe the appearance of a plasma cell.
- larger than lymphocytes, eccentric nuclei where chromatin is arranged as clock-face collections around nucleus.
- perinucelar clearing which appears a a lighter area surrounding nucleus as high golgi body count as antibody production.
what is the function of plasma cells?
- fully differentiated B-lymphocytes that produce antibodies.
describe the appearance of eosinophils.
- bilobed nucleus, with red staining granules.
what are the functions of eosiniphils?
- release of mediators in hypersensitivity and parasitic infections.
what are giant cells?
- multinucelated cells that are a fusion of multiple macrophages that join to destroy a pathogen.
- random scatter of nuclei if foreign body, horse shoe nucleus at langerhan, central collection at touton.
can you tell what kind of diagnosis it is by the proportion of cells?
- mainly plasma cells : rheumatoid arthritis.
- mainly lymphocytes : chronic gastritis.
- protozoal infection : mainly macrophages.
describe fibrosis as an effect of chronic inflammation using an example.
laying down of collagen as an attempt to regeneration.
- eg : cirrhosis
differentiate between crohns disease and ulcerative colitis.
- crohns can affect all of GI whereas Colitis only affects large bowel.
- crohns is a discontinuous formation of inflammation whereas colitis is continous.
what is granulomatous inflammation?
- collection of epithelioid histiocytes with surrounding lymphocytes.
- surrounds foreign body or immune mediated destruction of pathogens.
- caused by infections that are difficult to destroy.
- causes caseous necrosis in the centre.
- non caseating in GI in crohns, or sarcoidosis.
