Pathology Flashcards
What is hyperkeratosis?
Increased thickness of keratin layer
What is parakeratosis?
Persistence of nuclei in the keratin layer
What is acanthosis?
Increased thickness of epithelium
What is papillomatosis?
Irregular epithelial thickening
What is spongiosis?
Oedema fluid between squames that appears to increase prominence of intercellular prickles
What are the four classifications of inflammatory skin diseases?
Spongiotic
Psoriasiform
Lichenoid
Vesiculobullous
Name the main types of eczema?
Atopic
Irritant contact
Allergic contact
How does allergic contact eczema occur?
Langerhans cells present an antigen to T-lymphocytes
Sensitised memory T-cells in nodes recognise the antigens
T-lymphocytes are sent to the epidermis and infiltrate to cause a spongiotic eczematous reaction
What are lichenoid disorders characterised by?
Damage to the basal epidermis and resulting formation of cytoid bodies
What condition is associated with irregular sawtooth acanthosis?
Lichen planus
What condition can hypergranulosis and orthrkyperkeratosis be seen in?
Lichen planus
What are the three important immunobullous disorders to be aware of?
Pemphigus
Bullous pemphigoid
Dermatitis herpetiformis
What is pemphigus vulgaris?
An autoimmune condition in which IgG auto-antibodies are made against desmoglein 3
What is the end result seen in pemphigus vulgaris?
Acantholysis
What is acantholysis?
Lysis of intercellular adhesion sites between keratinocytes
What is seen on immunofluorescence in bullous pemphigoid?
Linear IgG and complement deposited around basement membrane
What is dermatitis herpetiformis?
A relatively rare autoimmune bullous disease with symmetrical intensely itchy lesions
What are the associations of dermatitis herpetiformis?
HLA-DQ2 haplotype
Coeliac disease
Perifollicular granulomas, vascular ectasia, inflammation with plasma cells and pustules are all associated with which condition?
Rosacea
What is the primary feature of immunobullous disorders?
Blisters
