Lecture 1 Introduction to General Dermatology Flashcards
What’s the largest organ in the body
Skin
What type of structures does the skin contain
Adnexal structures: hair, nails, glands, sensory structures
What is the epidermis
Outer layer- 3 cell types keratinocytes (squamous cells) majority of cells. Avascular
What is the dermis
collagen and elastin matrix with mucopolysaccharide gel also fibroblasts, dermal dendritis cells and macrophages
What is the hypodermic
(subcutaneous tissue): fat energy store, insulation, fibrous bands anchor skin to fascia
What are Melanocytes
makes melanosomes (collection of melanin) excreted and phagocytoses into keratinocytes
What are Langerhans
process antigens and migrate to lymph nodes to induce an immune response. Found in epidermis
Name the layers of the epidermis
Stratum corneum Stratum lucidum Stratum granulosum Stratum spinosum Stratum basale
What is the nail matrix
Where the nail starts to grow from
What is the hair cycle
Anagen- active goring phase
Catagen- 2-3 week phase growth stops/follicle shrink
Telogen- resting phase
What is the function of this skin
Thermoregulation Immunity Barrier Sensation Vitamin D synthesis Interpersonal Communication
Name external causes of skin disease
– Temperature, UV, chemical (allergen or irritant), infection, trauma (Dermatitis Artefacta)
– Photosensitivity- antibiotics, NSAIDs, anti-hypertensives
– Cold Injury
– Frostbite, Chilblains
– Skin Necrosis
– Cold Urticaria
Name internal causes of skin disease
– Systemic disease, genetics, drugs, infection
– Genetic- neurofibroma, Ichthyosis
– Drug reaction
– Autoimmune- Bullous Pemphigoid
What classifies as a small lesion
Less then 5mm
What is a macule
small circumscribed area (flat, discolouration)
