5: Pathology of rashes Flashcards
Name five functions of the skin.
Physical barrier
Thermoregulation
Maintains fluid / electrolyte balance
Vitamin D synthesis
UV protection
Immune surveillance
Sensory functions (touch, pressure, vibration etc.)
The epidermis is primarily made up of which kind of cell?
Keratinised stratified squamous epithelium / keratinocytes
Which cells are responsible for pigmentation and can be found at the dermo-epidermal junction?
Melanocytes
Which type of gland secretes onto the skin’s surface?
Eccrine glands
Sebaceous glands too
What is the ratio of melanocytes to basal cells in the epidermis?
1 : 10
melanocytes : basal cells
What do cells in the granular layer possess?
Keratohyalin granules
What joins cells in the prickle cell layer?
Desmosomes
What property of melanocytes allows them to transfer synthesised pigment to keratinocytes?
Dendritic projections
Langerhans cells are another example of ___ cells and monitor the epidermis for ___.
dendritic , antigens
Where are melanocytes found?
Basal layer only
Where are Langerhans cells found?
In both the upper and lower epidermis
Which elastic fibre makes up a lot of the dermis?
Collagen
Which property of collagen makes it ideal for the dermis?
Elastic
What are the two divisions of the dermis?
Papillary dermis
Reticular dermis
Which layer of the dermis contains appendages such as hair and glands?
Reticular dermis
How do melanocytes look under the microscope?
Pale pink
What is hyperkeratosis?
Thickening of the keratin layer
Tumours which penetrate the basement membrane are prone to ___.
metastasise
What is parakeratosis?
Persistence of nuclei in the keratin layer
What is acanthosis?
Increased thickness of epithelium
What is papillomatosis?
Irregular thickening of the epithelium - pointy, jagged basal layer
What is spongiosis?
Oedema of spaces in the epidermis
NOT neccessarily causing blisters - spongiotic diseases are not the same as vesiculobullous diseases
Which inflammatory cells appear in the epidermis during eczema?
Lymphocytes
Which cells signal for lymphocytes to infiltrate the epidermis in eczema?
Langerhans cells
What are the four main types of inflammatory skin disease?
Spongiotic - intraepidermal odema - e.g eczema
Psoriasiform - extension of rete ridges - e.g psoriasis
Lichenoid - basal layer damage - e.g lichen planus, lupus
Vesiculobullous - blistering - e.g pemphigus, pemphigoid, dermatitis herpetiformis
Which chronic inflammatory skin disease is found in 3% of people worldwide?
Psoriasis