Cutaneous Inflammation Flashcards
5 cardinal signs of acute inflammation
Heat
Redness
Swelling
Pain
Loss of function
Cells found in skin during inflammation
Neutrophil
Eosinophil
Lymphocyte
Plasma cell
Macrophage
Mast cell
What type of cell are langerhans cells
Dendritic
Langerhans location and function
Epidermis
Present antigens to CD4+ helper T cells and transport antigens to lymph nodes
What types of inflammation are Th1, TH2, and Th17 cells involved in
1 - neutrophilic inflam - extracellular
2 - monocytic inflam - intracellular
3 - eosinophilic, basophils, mast cell - helminths
Types of inflammation in skin
1 Mast cell mediated
2 Antibody mediated
3 Immune complex mediated
4 Delayed hypersensitivity
5 Granuloma formation
What type of inflammation causes urticaria
Mast cell mediated
What type of inflammation causes pemphigus
Antibody mediated
What type of inflammation causes vasculitis
Immune complex mediated
What type of inflammation causes contact allergic dermatitis
Delayed hypersensitivity
What type of inflammation causes TB and sarcoidosis
Granuloma formation
Causes of mast cell degranulation
Aspirin
NSAIDs
Serum factors
Insect stings
Allergens
What does mast cell degranulation release
Histamine
Leukotrienes
Prostaglandins
Platelet aggregating factor
Which cells are recruited and activated by mast cell degranulation
Monocytes and macrophages
Dendritic cells
T cells
Neutrophils basophils eosinophils
Epithelial cells
Effects of mast cell degranulation
Vascular leak
Bronchoconstriction
Intestinal hypermotility
Inflammation
Tissue remodelling
Phagocytosis
Antimicrobial activity
Degradation of endogenous toxic mediators
Effects of Histamine
Stimulates sensory nerves - itch
Bronchospasm
Smooth muscle contraction -> vessel leakage and oedema
Arteriole dilation -> headache + hypotension
Modulation of immune response
Which receptor does histamine modulate the immune response via
H2 receptor
Where is the Der P1 enzyme allergen found
Faecal pellets of dust mites
Which type of inflammation causes urticaria asthma and hay fever
Mast cell mediated
Anaphylaxis process
Antigen released into blood -> binds to IgE on basophils -> massive inflammatory mediators release -> bronchospasm + circulatory collapse
Urticaria
pruritic, pale, blanching swellings of the superficial dermis that last for up to 24 hours
Cutaneous demographism
Exaggerated urticarial response to pressure or scratching on skin
Allows words to be written on skin
Acute Angioedema
Sudden swelling often caused by allergic reaction
Which monoclonal antibody is now being used for resistant urticaria and asthma
Omalizumab
Desmosome
Junction betweeen keratinocytes
Acanthiolysis
loss of intercellular connections, such as desmosomes, resulting in loss of cohesion between keratinocytes
Occurs in pemfigus
Pemphigus vulgaris
autoimmune bullous diseases characterised by blisters and erosions of the mucous membranes and skin
Pemphigus vulgaris is most common variant
Pemphigus vulgaris on histology
Suprabasal splitting
Acanthiolysis
Pemphigus vulgaris treatments
Oral steroids
Immunosuppression - c mycophenolate mofetil, Azathioprine
Rituximab
Pathophysiology of complex mediated vasculitis
Immune complexes lead to ->
Deposition of fibrin
Vessel wall necrosis
Proteases degrade basement membrane zone
Leaky vessel extravasion of blood and oedema
Cutaneous manifestations of vasculitis
Erythema and oedema
Palpable pereira
Ulceration and necrosis
What antigen and antibody lead to systemic lupus erythematosus
DNA
anti-DNA
What antibody and antigen cause polyarteritis nodosa
HBsAg
Anti-HBsAb
Effects of IL2 and IFNgamma in allergic contact dermatitis
Promote Th1 response
Promote macrophage response
Skin inflammation 48-72hrs after challenge
Granuloma formation process
Mycobacterium tb ->
Clinal T cell expansion ->
Th1 cytokine excretion ->
Macrophage activation
Macrophages transform to form epithelioid macrophages and fuse to form langhans giant cells + foreign body giant cells ->
Combine to form granuloma
What can cause formation of a granuloma
Tb
Sarcoidosis
Foreign body granulomas - eg tattoos
What condition is caused by an autoimmune attack on the hair follicle
Alopecia areata
What condition is caused by an autoimmune attack on melanocytes
Vitiligo
What hair abnormalities can alopecia areata cause
Hair falling out
Hair regrowing white
Hair Turing white
Does vitiligo respond better to treatment on the hands or face
Face
What new drug can be used for alopecia areata and vitiligo
JAK inhibitors - ruxolitinib
Potential risks of JAK inhibitors
Thromboembolic disease
Cancer
