Introduction Flashcards
What are the layers of th skin?
Sub cutis
Dermis
Epidermis
What is the sub cutis?
Innermost layer of kin
Fat energy store that offers insulin and fibrous bands that anchor skin to fascia
What is the dermis?
Collagen and elastic matrix
What is in the dermis?
Mucopolysaccharise gel, fibroblasts, dermal dendrites cells and macrophages
What are the types of cell in the epidermis?
Keratinocytes
Langerhans
Melanocytes
What cells form the majority of th epidermis?
Keratinocytes
What is the function of langerhans cells in the epidermis?
Process antigens and migrate to lymph nodes to induce immune response
What are melanocytes?
Cells that are excreted and phagocytksed into keratinocytes
What are the layers of the epidermis?
Stratum corneum Stratum lucidum Stratum granulosum Stratum spinosum Stratum basale
What is the structure of the stratum corneum?
Dead cells in a hard protein envelope- cells contain keratin and are surrounded by lipids
What is the structure of the stratum lucidum?
Dead cells that lie within keratohyalin
What is the structure of he stratum granulosum?
Keratohyalin and a hard protein envelope form
What happens in the stratum granulosum?
Lamellar bodies release lipids and cells die
What is the structure of th stratum spinosum?
Keratin fibres and lamellar bodies
What happens on the stratum basale?
Cells divide by mitosis and some newly formed cells become the cells of the more superficial strata
What are the regions of the nail?
Lunula
Nail plate
Hyponychium
What are the 3 stages of hair growth?
Anagen
Catagen
Telogen
What is the anagen phase?
Active phase pf hair growth
What is the catagen phase?
Growth stops and follicle shrinks- 2-3 week phase
What is the telegenic phase?
Resting phase for 1-4 months, up to 10% hair on normal scalp
What are the functions of the skin?
Thermoregulation Immune Barrier Sensation Vit D synthesis Interpersonal communication
What are the thermoregulative functions f the skin?
Insulation
Heat transfer
What does the skin protect against?
MEchanical
Chemical
UV light
Microorganisms
What does the skin keep in?
Water
Electrolytes
Macromolecules
What sensations is skin involved in?
Temperature
Touch
Pain
What is UV light used for?
Convert 7-dehydrocholesterol to cholecalciferol
What can skin disease cause?
Disfirgurement Discomfort Disability Depression Death
What are the types of causes of skin disease?
External
Internal
What are the eternal causes of skin disease?
Temperature UV light Chemical Infection Trauma
What are the chemical causes of skin disease?
Allergen or irritant
What are the internal causes of skin disease?
Systemic disease
Genetics
Drugs
Infection
What is a macule?
Small circumscribed area
What s a patch?
Large circumscribed area
What is a papule?
Small raised area
What is a plaque?
Larger raised area
What isa vesicle?
Small, fluid filled
What is a bulla?
Large, fluid filled
What is a pustule?
Small pus filled
What is an abscess?
Large pus filled
What is an erosion?
Loss f epidermis
What is an ulcer?
Loss of epidermis and dermis
What is classed as “small”?
<5mm
What investigations should be done for a bacterial infection?
Charcoal swab- ask for microscopy, culture and sensitivities
What investigations should be done or a viral infection?
Viral swab for PCR- skin or vesicle/bulla
Is systemic illness, take throat swab
What is taken for a fungal infection?
Skin scraping
Nail clipping
Hair sample
What is the common way to take a skin biopsy?
Punch biopsy
When is a skin biopsy done?
When there is no sign of infection or unknown cause of reaction
