Pathology Flashcards
What type of epithelium is the epidermis?
Keratinised stratified squamous epithelium
Which epithelial layer contains prominent desmosomes?
Prickle cells layer
Which epithelial layer is rich in kerato-hyalin granules?
Granular layer
Which epithelial layer is a mitotic pool?
Basal cell layer
Where are melanocytes found?
Basal layer and dermo-epidermal junction
How do melanocytes look on histology?
Have a pale halo surrounding them
What is the function of menalocytes?
Transfer pigment to keratinocytes using dendritic processes
Where are Langerhan’s cells found?
Upper and mid epidermis
The dermis is made up of what?
Type 1 and 111 collagen, elastic fibres and ground substance
Which area of the dermis is thin and found just below the epidermis?
Papillary dermis
What area of the dermis makes up most of it and is made from thicker bundles of type I collagen?
Reticular dermis
Which part of the dermis contains the appendage structures?
Reticular dermis
What is the epidermal basement membrane made up of?
Laminin and collagen IV
What is hyperkeratosis?
Increased thickness of the keratin layer
What is parakeratosis?
Persistence of nuclei in the keratin layer
What is acanthosis?
Increased thickness of the epithelium
What is papillomatosis?
Irregular epithelial thickening
What is spongiosis?
Oedema fluid between cells increasing the prominence of prickles
If oedema between cells is severe, what will form?
Vesicles
What is the main spongiotic disease?
Eczema
Where is the damage in lichenoid disorders?
Basal layer (basement membrane)
Give two examples of licheniod disorders?
Lichen Planus and lupus
Vesiculo-bullous disorders are characterised by what? Give 3 examples.
Blistering: bullous pemphigoid, pemphigus vulgaris, dermatitis herpetiformis
What happens to the epidermis in psoriasis?
Increased turnover and hyperplasia
What is the Koebner phenomenon?
New lesions of psoriasis occurring at sites of trauma
In psoriasis, what mediates the attack on the keratin layer?
Complement which then attracts neutrophils
What is erythoroedema?
An acute form of psoriasis which is often caused by drugs and can affect the whole body
What will the rash look like in lichen planus?
Itchy, flat topped violet papules
Irregular saw-toothed acanthosis is associated with what condition?
Lichen planus
In lichen planus, there will be upper dermal infiltrate of what?
Lymphocytes
What are Wichen’s straie?
White stripes on the buccal mucosa seen in lichen planus
What is pemphigus?
A rare, autoimmune bullous disease normally in middle age with loss of integrity of epidermal cell adhesion
Pemphigus responds to treatment with what?
Steroids
What is the most common type of pemphigus?
Pemphigus vulgaris
Pemphigus vulgaris involves IgG antibodies against where?
Desmoglein 3 which maintains desmosomal attachments
What is the end result of pemphigus vulgaris?
Acantholysis (loss of cellular connections)
Where is the blister in bullous pemphigoid?
Subepidermal
Immunofluorescence shows what in bullous pemphigoid?
IgG and complement deposited around the basement membrane
If you send older lesions of bullous pemphigoid for histology, what can they mimic?
Pemphigus vulgaris
What bullous skin condition has a strong association with coeliac disease and HLA-DQ2?
Dermatitis herpetiformis
What will dermatitis herpetiformis cause?
Intensely itchy, symmetrical lesions
What is the hallmark of dermatitis herpetiformis?
Papillary dermal microabscesses
In dermatitis herpetiformis, there will be deposits of what in the dermal papillae?
IgA
The distribution of acne reflects what?
Sebaceous gland sites
Acne is caused by what?
Increased androgens at puberty
What causes the infection in acne?
Anaerobic bacteria- corynebacterium acnes
Where are common sites to get dermatitis herpetiformis?
Elbows, knees, buttocks
Rosacea is more common in which sex? What are some triggers?
Females: spicy food, alcohol, sunlight, stress
What happens in rosacea?
Recurrent facial flushing with visible blood vessels, pustules and thickening of the skin (rhinophyma)
Some cases of rosacea respond to what medication?
Tetracyclines