Skin pathology Flashcards
What are the layers of the skin?
- Epidermis (top layer) = keratinocytes
- Dermis = sweat glands, sebaceous glands and hair follicles
- Subcutis = fat cells
What is the effect of age on the skin?
The epidermis is thinned, collagen fires degraded
What are examples of vesiculobullous inflammatory skin pathologies? 3
- Bullous Pemphigoid
- Tense bullae in flexural surfaces
- IgG and C3 attack Basement membrane
- Pemphigus Vulgaris
- like previous but bullae not as tense
- Pemphigus antibodies which attacks the proteins between keratinocytes in the epidermis
- Pemphigus Foliaceus
- V rare
- v fragile bullae
- caused by IgG
What is an example of a spongiotic inflammatory skin pathology?
Discoid Eczema
- > Pruritic lesions across the flexural surfaces i.e. elbows&knees
- > Associated with Atopy and Contact Dermatitis.
- > T cell mediated
- > The developement of fluid within the keratinocyte lining i.e. Spongiosis
- > Eosinophilic Infiltration
What is an example of a Psoriaform inflammatory skin pathology?
Plaque Psoriasis
- > Typified by the formation of silvery plaques
- > across extensor surfaces i.e. knuckles, elbows and knees
- > rapid turnover of keratinocytes
What is an example of a Lichenoid inflammatory skin pathology?
Lichen Planus
- > Buccal mucosa
- > White lines inside the mouth o.e. Wickams Tree
What is an example of a Vasculitic inflammatory skin pathology?
Pyoderma Gangrenosum
Ulcer on patients lower leg.
- > Also Inflammatory
- > Often a presentation of some underlying pathology
i. e. ass. With Leukaemia, IBD, Hepatitis, Sarcoid, TB, SLE - > very non specific cells
What are examples of benign neoplastic skin pathologies? 4
- Seborrhoeic Keratosis
- > Very common
- > Proliferation of keratinocytes which produce keratin and end up trapped.
- > easily caught on clothing
- Sebaceous Cyst
-> Very common, short surgical diagnosis/case.
Round smooth surface, central punctum and doesn’t move.
-> epidermal cyst not sebaceous
- Benign Junctional Naevus
Benign clumps of Melanocytes just underneath the basement membrane
- Compound Naevus
What is an example of a Dysplastic neoplastic skin pathology?
Bowen’s Disease
Precancerous lesions i.e. dysplastic keratinocytes which haven’t invaded through the basement membrane
-> This predisposes to SCC
What are examples of malignant neoplastic skin pathologies? 3
- Basal Cell Carcinoma
-> Typically occur on elderly sun damaged skin secondary to UV light
Rolled edge, central ulceration.
-> epithelial keratinocyte cells invade through the basement membrane into the underlying dermis.
- Squamous Cell Carcinoma
- > Predisposed by DYSPLASIA. - Malignant Melanoma
Biggest Killer of uni student age group
- > Irregular Border, Irregular Shape, Irregular Pigement, Ulcerated Bleeding
- > Itchy
- > Fast Growing
- > melanocytes
Infiltration of what kind of cell is seen in Bullous Pemphigoid?
Eosinophils
Where does Pemphigus Vulgaris usually start?
Mouth
What cells are recruited in Plaque Psoriasis?
neutrophils
What are the different types of inflammatory skin pathologies? 5
- Vesiculobullous
- Spongiotic
- Psoriaform
- Lichenoid
- Vasculitic
How are skin cancers staged?
Epithelial cancers = diameter
melanomas = depth
