MoD week 2-3 chronic and acute inflammation Flashcards
what is acute inflammation?
response of living tissue to injury
what are the clinical signs of acute inflammation?
rubor, color, tumour, dolor, loss of function
what is vasodilation in acute inflammation?
increase permeabiity, and hydrostatic pressure to form exudate
gaps in endothelium allows exudation (plasma proteins), adherence, margination and emigration through basement membrane
recruits macro and lymphocytes
what are the mediators of acute inflammation?
histamine (stored in mast cells granules), serotonin (stimulate fibroblasts & platelets), prostaglandins (vasodilate, cause pain & fever), leucotrines (permeability), bradykinin (dilator, produce pain), complement (C3a, C4a, C5a), cytokines, endotoxins
conditions of acute inflammation
hereditary angiodema
alpha 1 anti trypsin deficiency
CGD (chronic granulomatous disease)
what is hereditary angiodema?
C1 esterase inhibitor deficiency
patient has attacks of non-itchy cutaneous angio-oedema
death in larengeal involvement
what is a-1 antitrypsin deficiency?
no inhibition of proteases
breaking down lung tissue causing emphysema
what is chronic granulomatous disease?
no O2 burst so granulomas formed everywhere
(unable to generate free radicals)
phagocytes can’t kill them and no free radicals leading to chronic infections
what causes chronic inflammation
takes over from acute
begins denovo (autoimmune)
alongside acute (abscess) - prolonged exposure to toxic agents
chronic persistent infections (arise denovo)
what are the processes of neutrophils working in acute inflammation?
margination - stasis causes neutrophils to line at edge of endothelium
rolling - neutrophils roll along endothelium
adhesion - to endothelium
emigration - of neutrophils out of capillary walls
What are the possible complications of chronic inflammation?
granulomas,
excessive fibrosis: fibroblasts stimulated by cytokines (excess collagen production)
impaired function: myofibroblasts contract e.g. blocking flow duct of liver
atrophy: muscle wasting
tissue destruction
What are giant cells?
fusion of macrophages due to frustrated phagocytosis
What are the 3 types of giant cells?
langans
foreign body
toutons
what are langans giant cells?
TB
have a nucleus like horseshoe - periphery
What are foreign body giant cells
present if there are foreign bodies
random nuclei
what are toutons giant cells
in lesions with high lipid content e.g. fat necrosis + xanthoma
ring nuclei in centre of cell, can see foam cells (macrophage ingest oxidised lipids)
what are the principle cells of chronic inflammation?
macrophage
lymphocytes
eosinophils
fibroblasts
what is the funciton of macrophage?
phagocytosis, present antigens to immune system
stimulate angiogenesis
function of lymphocyte?
B type (plasma cells) produce antibodies T type (killer cells) + cytotoxic functions, process antigens, secrete cytokines
function of eosinophils
allergic rections, parasitic infestations
function of fibroblasts
make collagen, elastin + GAG, differentiate into myofibriblasts (cells that can contract)
major clinical examples of chronic inflammation
chronic cholecystitis peptic ulcer ulcerative colitis chrons cirrhosis grave's RA
what is chronic cholecystitis?
repeated acute inflammation leading to fibrosis of the gall bladder
what is peptic ulcer?
helicobacter pylori
imbalance between mucosal defence and acid production
necrosis
