Histopath - skin Flashcards
normal structures seen in the dermis?
- Sebaceous glands
- Small nerves + vessels
- collagen + elastic fibres
- Hair follicles
How does normal skin on the soles of feet compare to normal skin on the face?
Feet: v thick epidermis
Face: bare sebaceous glands
Name 4 vesicobullous diseases
PemphigoiD (deep)
PemphiguS (superficial)
Pemphigus Foliaceous (vv superficial)
Dermatitis herpetiformis
Pathophysiology of pemphigoid?
Deep bullae
IgG binds to hemidesmosomes in BM –> sub epidermal bullae form
Histology of pemphigoid?
Sub epidermal bullae + LINEAR IgG DEPOSITION
Which vesicobullous disease is associated with IgA deposition?
Dermatitis herpetiformis
Differences between bullous pemphigoid vs dermatitis herpetiformis?
Both are deep bullae BUT
- Pemphigoid = IgG. DH = IgA
- Pemphigoid = elderly flexures.
- DH = Coeliac + extensors.
Which vesicobullous diseases is superficial?
Pemphigus vulgaris + foliaceous
Pathophysiology + histology of pemphigus vulgaris?
Pemphigus Vulgaris
- IgG binds to desmosomal proteins in epidermis –> intraepidermal bullae form
- IgG deposits between cells in a netlike pattern
What is the most superficial of vesicobullous diseases? where are the bullae?
Pemphigus follaecous
Bullae are SUBCORNEAL
3 histological features in acute eczema?
1) Spongiosis
2) Inflammatory cell infiltration
3) Dilated dermal CAPILLARIES
Type of hypersensitivity in contact dermatitis?
IV
Auspitz’ sign
PSORIASIS
- pin point bleeding on rubbing
Koebner phenomenon
PSORIASIS
- psoriatic esions form at sites of trauma
Histological findings in psoriasis
TEST TUBES IN A RACK appearance (micro abscesses)
Characteristic pathological finding in Lichen Planus
BAND OF T-CELLS beneath the epidermis
the 5 Ps of clinical features in lichen planus
Pruritic Purple Polygonal Papules Plaques
define a granuloma
Collection of activated macrophages w secretory activity
Painful ulcer + rolled edge
- IBD, malignancy, sarcoidosis
Pyoderma gangrenosum
What kinda cysts are seen in seborrheic keratosis
Keratin cyst
“stuck on” appearance + benign
Seborrheic keratoses
Name a disease which is a pre-malignant skin neoplasm?
Bowen’s disease
Key histological feature of basal cell carcinoma
Palisading nuclei
When bowen’s disease spreads and invades the dermis, what is this?
Squamous cell carcinoma
Posh term for moles
Melanocytic nevi
Most important prognostic factor for malignant melanoma?
Breslow thickness
