Background

Question 1

history

Answer 1

occupation important
HPC: duration, location, initial appearance, evolution, associated symptoms (itch, pain, bleeding), treatments tried

RF: age, sunburn, occupation, smoking, travel

impact/ICE: psychosocial important

Question 2

examination

Answer 2

DCM: rashes/eruptions
ABCDE; 5S: site, size/shape, symmetry, surface. surrounding
‘SCAM’: size/shape, colour, associated change, morphology/margin

palpate: surface, consistency, mobility, tenderness, temp , illumination, LN

check hair, nails, oral mucosa

Question 3

skin anatomy

Answer 3

epidermis:
- corneum: horny cells; keratin
- lucidum: thick skin only; pale compact keratin
- granulosum: keratohyaline granules and lipids; looser
- spinosum: ‘prickle cells’; differentiation
- basale: dividing cells
dermis: papillary and reticular; appendages, nerves, elastin/collagen, BV
subcutis: fatty CT

keratinocytes, Langerhan’s (APC), melanocytes, Merkel’s (nerve endings)

Question 4

skin function

Answer 4

protection (Barrier)
temperature
sensation
vitamin D synthesis
immunosurveillance
appearance/cosmesis

Question 5

hair

Answer 5

modified keratin; shaft, bulb, and melanocytes

lanugo: fine; fetus/AN
vellus: fine short hair; all surfaces
terminal hair: course, long; scalp, eyebrows, eyelashes, pubic, pits, legs, face

anagen (grow), catagen (Regress), telogen (shed/rest)

Question 6

nails

Answer 6

nail plate (keratin)
matrix
proximal nail fold
nail bed (Capillaries)

Question 7

glands

Answer 7

sweat: SANS, temp reg; eccrine and apocrine (smelly, EAM, areola)
sebaceous: sebum from hair follicles; lubricate + waterproof; androgens

Question 8

wound healing

Answer 8

haemostasis: constriction, platelets, fibrin clot
inflammation: dilatation, NP/MP migration, phagocytosis
proliferation: granulation (fibroblast), angiogenesis, re-epithelialisation (migration)
remodelling: collagen reorganisation, scar maturation

Question 9

rash description

Answer 9

DCM

Question 10

pigmented lesion

Answer 10

ABCDE + compare to other lesions

asymmetry
border: smooth, reg, reg irreg, irreg
colour: uniform, gradient/change, random
diameter
evolution and elevation

Question 11

individual lesion

Answer 11

5S: site, size/shape, symmetry, surface, surroundings

SCAM: size/shape, colour, associated change, morphology/margin

Question 12

erythema DDx

Answer 12

psoriasis: extensors, scaly, plaques
drugs incl. EM/SJS/TEN
eczema: excoriation, flexures
mycosis: annular, scaly rim, central clearing
pityriasis rosea: herald patch, scaly
lymphoma: LN palpable
idiopathic
infection: erythrasma, candidiasis, cellulitis

Question 13

purpura DDx

Answer 13

thrombocytopenic:

• meno septicaemia: acute, Sx, petechiae, bruise, hge, necrosis
• DIC: trauma/Ca/obstetric/liver, bleeding, pet/ecc, hge, necrosis
• ITP: ?HSM, well, preceding viral

nonTP:

• drugs
• vasculitis/CTD: systemic upset, dependent areas, palpable painful purpura
• aged skin: sun-damaged, non-palpable purpura, systemicall well

Question 14

pruritus DDx

Answer 14

derm:

• coeliac: dermititis herpetiformis (pap/ves)
• eczema: dry, erythema, vesicles, exudate
• scabies: burrows and rubbery nodules
• lichen planus (purple + lacy white), lichen sclerosis (white thinning)
• urticaria: pink wheals; round/annular/polycyclic, triggers
• chicken pox: vesicles

non-derm:

• cholestatic jaundice
• drugs: aspirin, alcohol, morphine, codeine
• pregnancy
• uraemia
• DM/thyroid
• malignancy (e.g. blood Ca)
• iron deficiency, PRV
• xerosis
• psych

Question 15

depigmentation DDx

Answer 15

vitiligo
inflammatory depigmentaion
DLE (lupus)
pityriasis abla
piebaldism
Addison's (hyperpigment contrast)
pityriasis versicolour

Question 16

Koebner’s

Answer 16

psoriasis
lichen planus
viral warts
molluscum contagiosum
sarcoidosis

Question 17

blisters DDx

Answer 17

impetigo
insect bites
HSV/HZV
acute contact dermatitis
pompholyx: tiny blisters
burns
bullous pemphigoid: hge tense blisters; IgG in hemidesmo/BM
pemphigus vulgaris: superfical 'shedded' blisters; IgG desmosome (epidermis), Nikolsky sign (shedding)

Question 18

red swollen leg DDx

Answer 18

cellulitis: painful, trauma/ulcer, diffuse edge, systemic upset
erysipelas: painful, spreading, trauma/ulcer, defined, systemic upset
DVT: painful, RFs, may be cyanotic, systemically well, tender
chronic venous insufficiency: heavy/ache, better with move; blue/purple, oedema, varicose veins, LDS, eczema, venoux ulcer
necrotising fasciitis: extremely painful, systemic upset, rapid spread

Question 19

anaphylaxis

Answer 19

lip/tongue swelling
bronchospasm
hypotension
angioedema
urticaria: itchy wheals

Rx: adrenaline (0.5ml 1:1000), antiH (10-20mg), CST (100mg)

Question 20

acne DDx

Answer 20

Rosacea: no comedones
peri-oral dermatitis: no comedones
folliculitis: no comedones
DLE
drug eruption
endocrine: sudden, severe, hyperandro, menstrual

Question 21

erythema multiforme DDx

Answer 21

infection: strep (Ag hypersensitivity
HZV (65% of cases)
drugs: penicillin, sulphonamides, phenytoin, allopurinol
urticaria: 2 colours (annular wheal),