Examination Flashcards
How would describe a skin lesion?
Use SCAM
S= size C= colour A= associated secondary change M= morphology, margin (border)
If the lesion is pigmented use ABCD (any of these features increase the likelihood of a melanoma)
A= asymmetry B= irregular Border C= two or more Colours within the lesion D= Diameter >6mm
What is the general structure of a dermatology examination?
Look and describe the lesion
Palpate individual lesions for: surface, consistency, mobility, tenderness and temperature
Systemic check: examine the nails, scalp, hair, mucous membranes
General examination of all systems
What is a comedone?
A plug in a sebaceous follicle, contains altered sebum, bacteria and cellular debris
Can either present as open or closed
What do the following mean…
1- generalised 2- widespread 3- localised 4- flexural 5- extensor 6- Pressure areas 7- dermatome 8- photosensitive 9- koebner phenomenon
1- all over the body
2- extensive
3- one area of skin only
4- body folds- groin, neck, behind ears, popliteal, antecubital fossa
5- knees, elbows, shins
6- heels, ankles, sacrum, buttocks
7- an area of skin supplied by a single spinal nerve
8- sun exposed area (face, neck, back of hands)
9- linear eruption arising at the site of trauma
What do the following configurations (pattern or shape of grouped lesions) mean..
A) discrete B) confluent C) linear D) target E) annular F) discoid/ nummular
A) individual lesions which are separated from each other
B) lesions merging together
C) in a line
D) concentric rings (like a dartboard)
E) like a circle or ring (tinea corporis- ringworm)
F) coin shaped
How can you describe the colour of a lesion…
Erythema (due to inflammation and vasodilatation) blanches on pressure
Ie: palmar erythema
Purpura (red or purple colour which is due to bleeding into the skin or mucous membrane) Doesn’t blanch on pressure
Purpura can either be petechiae (small pinpoint maccules) or ecchymoses (larger bruise like patches)
Hypopigmentation (areas of paler skin)
Depigmentation (white skin due to absence of melanin)
Hyperpigmentation (increased melanin pigmentation)
Give an example of the following…
erythema
Purpura
Hypopigmentation
Depigmentation
Hyperpigmentation
A) palmar erythema- seen in cirrhosis
B) henoch schonlein purpura (palpable small vessel vasculitis)
C) pityriasis versicolor (superficial fungal infection)
D) vitiligo
E) melasma
How do you describe the morphology of a lesion?
Macule= flat area of altered colour ie: freckles
Patch= larger flat area of altered colour or texture ie: naevus flammeus/ port wine stain)
Papule= a solid raised lesion <0.5cm in diameter
Nodule= a solid raided lesion >0.5cm in diameter
Plaque= palpable scaling raised lesion >0.5cm in diameter
Vesicle (small blister)= raised clear fluid filled lesion < 0.5cm in diameter
Bulla= raised clear fluid filled lesion >0.5cm in diameter
Pustule= pus containing lesion which is <0.5cm in diameter
Abscess= localised accumulation of pus in the dermis or subcut tissues
Wheal= transient raised lesion due to dermal oedema
Boil/furuncle= staphylococcal infection around or within a hair follicle
Carbuncle= staph infection of adjacent hair follicles (multiple boils/furuncles)
What is meant by secondary lesions?
Lesions which evolve from the primary lesions Examples... - excoriation - lichenification - scales - crust - scar - ulcer - fissure (epidermal crack often due to excess dryness) - striae
What is meant by…
A) alopecia
B) hirsutism
C) hypertrichosis
A) loss of hair
B) androgen dependent hair growth in a female
C) non androgen dependent pattern of excessive hair growth ie: pigmented naevi
What is clubbing and what is it caused by?
Loss of angle between the posterior nail fold and nail plate
Caused by…
- suppurative lung disease
- cyanotic heart disease
- IBD
- idiopathi
What is koilonychia and what is it associated with?
Spoon shaped depression of the nail plate
Iron deficiency anaemia, congenital, idiopathic
What is onycholysis? What is it caused by?
Seperation of the distal end of the nail plate from the nail bed
Fungal nail infection, trauma, psoriasis, hyperthyroidism
What is pitting?
Punctate depressions of the nail plate
Associations- psoriasis, eczema, alopecia areata
What are the functions of normal skin?
Protective barrier against environmental insults Temperature regulation Sensation Vit D synthesis Immunosurveillance Appearance/cosmesis
What are skin appendages?
Structures formed from skin derived cells- hair, nails, sebaceous glands, sweat glands.
There are four main cell types of the epidermis, what are they and what are their function?
Keratinocytes, langerhans cells, melanocytes and merkel cells
Keratinocytes- produce keratin as a protective barrier
Langerhans cells- present antigens and activate T lymphocytes for immune protection
Melanocytes- produce melanin, this gives pigment to the skin and protects the cell nuclei from UV radiation induced DNA damage
Merkel cells- contain specialised nerve endings for sensation
What are layers of the epidermis?
Deepest to most superficial….
- stratum basale (basal cell layer- actively dividing cells, deepest layer
- stratum spinosum (prickle cell layer)
- stratum granulosum
- stratum corneum (layer of keratin, most superficial layer)
What may pathology of the epidermis involve?
A) changes in epidermal turnover time (psoriasis- reduced epidermal turnover time)
B) changes in the surface of skin or loss of epidermis- scales, crusting, exudate, ulcer
C) changes in pigmentation
What is the average epidermal turnover time?
Turnover= migration of cells from the basal cell layer to the horny layer
It is about 30 days
What is the dermis made up of?
Collagen
Glycosaminoglycans
Elastin
Collectively they provide the dermis with strength and elasticity
The dermis also contains immune cells, nerves, skin appendages as well as lymphatic and blood vessels.
What might the pathology of the dermis involve?
Changes in the contour of the skin/loss of dermis
Disorders of skin appendages- hair/acne (sebaceous glands)
Changes related to lymphatic and blood vessels
What is the role of sebaceous glands?
Sebaceous glands produce sebum via. hair follicles (collectively called a pilosebaceous unit), when they secrete sebum onto the skin surface it lubricates and waterproofs the skin
How are sebaceous glands stimulated?
They are stimulated by the conversion of androgens to dihydrotestosterone and therefore become active at puberty
What does pathology of sebaceous gland involve?
Increased sebum production and therefore bacterial colonisation- acne
Sebaceous gland hyperplasia
What is the role of sweat glands and what are they innervated by?
Sweat glands regulate body temperature
They are innervated by the sympathetic nervous system
What are the two types of sweat glands?
Eccrine and apocrine
Eccrine- widely distributed in the skin
Apocrine- found in the axilla, areolae, genitals and anus and modified glands are found in the external auditory canal
what are the stages of wound healing?
Haemostasis (vasoconstriction and platelet aggregation, clot formation)
Inflammation- vasodilatation, migration of neutrophils and macrophages
Phagocytosis of cellular debris and invading bacteria
Proliferation- granulation tissue formation and angiogenesis
Re- epithelialisation
Remodelling- collagen fibre re-organisation, scar maturation
