Dermatology Flashcards
Name the four major cell types within the epidermis
Keratinocyte - protective barrier
Langerhan cells - antigen presenting cells
Melanocyte - produce melanin
Merkel cells - contain specialised nerve endings for sensation
What are the four layers of the epidermis
Stratum corneum
Straum granulosum
Stratum spinosum
Stratum basale
(+ stratum lucidum)
What are the functions of the subaceous glands
Sebaceous glands produce sebum through hair follicles
Secrete sebum on to skin to lubricate the skin
Active after puberty
What are the functions of eccrine and apocrine glands
Apocrine and eccrine glands help regulate body temperature and are innervated by the SNS
Eccrine are widespread
Apocrine are active following puberty and are found in axillae, areolae, genitalia, anus
Describe the structure of hair
Hair consists of modified keratin
Divided into hair shaft and hair bulb
Three types: lanugo, vellum (short hair) and terminal hair (coase, long hair)
Have a cycle of anagen -> catagen -> telogen
Describe the structure of nails
Nails consist of a nail plate which arises form the nail matrix at the posterior nail fold and rests on the nail bed
What is erythroderma and name some causes
Erythroderma - total skin failure. Have erythematous and exfoliative skin
Causes include: psoriasis, eczema, drugs, cutaneous T cell lymphoma
What is eczema
Eczema is an inflammatory condition affecting the epidermis
There is epithelial disruption with vesicles, bullae and/or papules
Will have severe pruritis
May be acute (rapidly progressing rash) or chronic (longstanding irritable area)
Types include atopic, irritant contact, allergic contact, dry skin
What is the treatment of eczema
Reduce bathing/showering
Use soap-free cleansers
Wear soft, smooth clothers
Protect skin from irritants
Use topical steriod creams or ointments on the itchy patches
Use antihistamines to reduce the inflammation
Make sure to moisturise the skin to prevent it drying
What is acne vulgaris
Acne vulgaris is a common form of acne. Mainly affects adolescents but may persist
Commonly affects the face but may spread to neck, chest or back
Lesions are centred on pilosebaceous units
What lesions can be seen in acne vulgaris
Superficial lesions - open and closed commedones, papules, pustules
Deeper lesions - nodules, pseudocytes
Secondary lesions - excoriations, erythematous macules, pigmented macules
What is psoriasis
Psoriasis is an inflammatory skin condition where there is clearly defined, red and scaly plaques
Can occur at any age and tends to persist life long
There is a genetic risk factor
How does psoriasis present and what are the risk factors
Presents with symmetrically distributed, red and scaly plaques with well defined edges
Plaques usually slivery white
Common on scalpy, elbows and knees
Risk factors include - smoking, obesity, excessive alcohol, medication, stress
What is one of the most common causes of urticaria
Viral infection
