Inflammatory responses Flashcards
What are the 5 causes of acute inflammation?
- Physical agents (e.g. trauma, heat, cold, UV light, radiation)
- Irritant chemicals (e.g. acids, alkali)
- Microbial infections (e.g. pyogenic bacteria)
- Immune-mediated hypersensitivity reactions
- Tissue necrosis (e.g. myocardial infarction)
In acute inflammation, what 3 forms of vascular response occur?
Vasodilation
Increased vascular permeability
Inflammatory oedema
As part of the vascular response to acute inflammation, endothelial intracellular proteins contract under the influence of chemical inflammatory mediators - name 5 of them?
Histamine
Serotonin
Bradykinin
Nitric oxide
Leukotriene B4
In acute inflammation, chemotaxis of neutrophils migrating towards the site of tissue injury, attracted by chemotaxis such as what (name 3)?
Leukotrienes
Complement components
Bacterial products
Chronic inflammation usually develops as a primary response to 1 of 4 situations - name them?
- Microorganisms resistant to phagocytosis or intracellular killing mechanisms (e.g. TB, leprosy).
- Foreign bodies, which can be endogenous (e.g. bone adipose tissue, uric acid crystals) or exogenous (e.g. silica, suture materials, implanted prostheses).
- Some autoimmune diseases (e.g. rheumatoid arthritis).
- Primary granulomatous diseases (e.g. Crohn’s, sarcoidosis).
The site of chronic inflammation is dominated by what 3 things?
- Lymphocytes
- Plasma cells for antibody production
- Macrophaes for phagocytosis (some macrophages fuse to form multinucleate giant cells)
Macrophages in inflamed tissue are formed from the transformation of what?
Monocytes
In both acute and chronic inflammation, fever can occur, why?
Neutrophils and macrophages produce pyrogens (e.g. IL-1) which act on the hypothalamus
Why can lymphadenopathy happen in acute and chronic inflammation?
Reactive hyperplasia of the mononuclear phagocyte system
In granulomatous chronic inflammation, what is important for 1. initiating granuloma formation 2. causing them to enlarge 3. maintains them?
- IL-1
- IL-2
- TNF-alpha
Metaplasia, in which one cell type is switched for another, thought to be the result of progenitor cells differentiating into a new cell type, is seen almost exclusively in what kind of cell?
Epithelial cells
Cell recovery is associated with removal of damaged components by what process?
Autophagy
Name 3 forms of cell damage that tend to be reversible?
- Swelling of endoplasmic reticulum and some mitochondria
- Loss of ribosomes
- Cell stress response
Apoptosis, a controlled form of cell death in which no cellular contents are released from the dying cell, and thus no inflammation is seen, may be induced in what 2 main ways?
- By the engagement of surface death receptors e.g. TNF-alpha (extrinsic pathway)
- Through cellular injury (intrinsic pathway)
What is the most common form of necrosis?
Coagulative necrosis - characterised by the loss of cell nuclei, but with general preservation of the underlying architecture
What type of necrosis is typically seen in the brain following cerebral infarction?
Liquefactive necrosis - leads to complete loss of cellular structure and conversion into a soft, semi-solid mass
What type of necrosis is most commonly seen in TB?
Caseous necrosis - histologically, the complete loss of normal tissue architecture is replaced by amorphous, granular and eosinophilic tissue with a variable amount of fat and an appearance reminiscent of cottage cheese
What type of necrosis is seen in malignant hypertension?
Fibrinoid necrosis - in malignant hypertension increased arterial pressure results in necrosis of smooth muscle. Eosinophilic and fibrinous deposits are seen.
What type of necrosis typically follows trauma or from enzymatic lipolysis in acute pancreatitis?
Fat necrosis
What is gangrenous necrosis?
Necrosis with putrefaction of tissues due to exposure to air (dry gangrene) or infection (wet gangrene). The tissue is black due to iron sulphide from degraded haemoglobin.
Name 8 different inflammatory mediator systems which interact to produce inflammation?
The complement system
Kinins
Prostaglandins and leukotrienes
Platelet activation factors
Vasoactive amines
Cytokines
Nitric oxide
Acute-phase proteins (APPs)
The kinin system is stimulated by which activated coagulation factor?
Activated coagulation factor XII
Cytokines are secreted by what?
Leucocytes
Nitric oxide, a potent vasodilator, is released from what?
Endothelial cells and macrophages
The acute phase response is a systemic reaction to infection or tissue injury induced by increased circulating levels of what?
IL-1, IL-6 and TNF-alpha
C-reactive protein (CRP) is an acute phase protein produced by the liver. CRP binds to what, found on the surface of many bacteria?
Phosphorylcholine
The erythrocyte sedimentation rate (ESR) is particularly helpful in diagnosing and monitoring treatment in what 2 inflammatory disease?
Temporal arteritis and polymyalgia rheumatica
ESR is raised with inflammation and infection but may also be raised in what other situations?
Anaemia
Renal impairment
Pregnancy
Old age
Multiple myeloma or Waldenstrom’s macroglobulinaemia
Although a low ESR is not usually important, it can be seen in what diseases?
Polycythaemia
Extreme leucocytosis
Some protein abnormalities
Raised antinuclear antibodies are almost always present in what condition?
SLE
High levels of rheumatoid factor are associated with which 2 conditions?
RA and Sjogren’s syndrome
Anticardiolipin antibodies are the most commonly detected antiphospholipid antibodies and are associated with what condition?
Primary antiphospholipid syndrome
c-ANCA (cytoplasma) are associated with which conditions?
Granulomatosis with polyangiitis (Wegener’s), micropolyarteritis, Churg-Strauss, polyarteritis nodosa and RPGN
c-ANCA (cytoplasma) are associated with which conditions?
Granulomatosis with polyangiitis (Wegener’s), micropolyarteritis, Churg-Strauss, polyarteritis nodosa and RPGN
c-ANCA (cytoplasma) are associated with which conditions?
Granulomatosis with polyangiitis (Wegener’s), micropolyarteritis, Churg-Strauss, polyarteritis nodosa and RPGN
p-ANCA (perinuclear) is associated with what conditions/
Microscopic polyangiitis, Churg-Strauss, anti-GBM disease, crescentic glomerulonephritis and Wegener’s
Pernicious anaemia is associated with what antibody?
Intrinsic factor
Autoimmune gastritis is associated with what antibodies?
Parietal cell antibodies
Coeliac disease is associated with what antibodies?
IgA anti-tissue transglutaminase (anti-tTG), anti-gliadin and endomysial antibodies (EMAs)
Primary biliary cirrhosis is associated with what antibodies?
Antimitochondrial antibodies
Autoimmune hepatitis is associated with what antibodies?
Anti-smooth muscle antibodies
Type 1 diabetes is associated with what antibodies?
Glutamic acid decarboxylase (GAD), islet cell and insulin antibodies
Autoimmune thyroid disease is associated with what antibodies?
Anti-thyroid peroxidase (TPO), TSH (thyrotropin) receptor and thyroglobulin (TG) antibodies
Name 2 conditions steroid cell antibodies are associated with?
Addison’s disease
Autoimmune gonadal failure
Acetylcholine receptor antibodies are associated with what condition?
Myasthenia gravis
Goodpasture’s syndrome is associated with what antibodies?
Anti-glomerular basement membrane (GBM) antibodies
Name 3 conditions that cardiac muscle antibodies are associated with?
Heart failure
Myocarditis
Dilated cardiomyopathy
The dermatological condition pemphigus is associated with which antibody?
Intra-epidermal/desmosome antibody
The dermatological condition pemphigoid is associated with which antibody?
Basement membrane zone antibody
