Dermatology Flashcards
How to examine a skin lesion
Inspect - site, number of lesions, distribution and configuration
Describe - size, shape, colour, secondary changes, morphology, margin
If pigmented: Asymmetry, irregular Border, two or more Colours, >7mm Diameter
Palpate - consistency, mobility, tenderness, temperature
Systemic check - nails, scalp, hair + mucous membranes
What is a lesion?
Area of altered skin
Definition of a rash
An eruption
Definition of a naevus
Localised malformation of tissue structures
Definition of a comedone
Plug in sebaceous follicle containing sebum, bacteria and cellular debris
Open = blackheads
Closed = whiteheads
Definition of generalised
All over body
Definition of widespread
Extensive
Definition of localised
One area of skin only
Pressure areas
Sacrum, buttocks, ankles, heels
Photosensitive
Affects sun-exposed areas such as face, neck and back of hands
What is distribution?
Pattern of spread of lesions:
Generalised, widespread, localised?
Flexor/ extensor/ pressure areas/ dermatomes/ photosensitive area?
What is configuration?
Pattern or shape of grouped lesions:
Discrete, confluent, linear, target, annular, discoid
Definition of discrete
Individual lesions separated from each other
Definition of confluent
Merging together
Definition of linear
In a line
Definition of target
Concentric rings (bullseye)
Definition of annular
Rings
Definition of discoid
Coin shaped/ round
Types of colour of a lesion
Erythema/ purpura
Hypo/ hyper/ depigmented
Definition of erythema
Redness which blanches
Definition of purpura
Red or purple that does not blanch
Definition of petechiae
Purpura - small pinpoint macules
Definition of ecchymoses
Purpura - large bruise like patches
Hypo/ hyper/ depigmented
Hypo = paler skin Hyper = darker skin De = white skin due to absence of melanin
Definition of morphology
Structure of lesion
Definition of macule
Flat area of altered colour (freckle)
Definition of patch
Large flat area of altered colour
Definition of papule
Solid raised lesion <0.5cm (xanthomata)
Definition of nodule
Solid raised lesion >0.5cm
Definition of plaque
Palpable scaling raised lesion >0.5cm (psoriasis)
Definition of vesicle
Raised, clear fluid filled lesion <0.5cm (acute hand eczema)
Definition of bulla
Raised, clear fluid filled lesion >0.5cm (reaction to insect bites)
Definition of pustule
Pus containing lesion <0.5cm (acne)
Definition of abscess
Localised accumulation of pus in dermis
Definition of weal
Transient raised lesion due to dermal oedema (urticaria)
Definition of boil/ furuncle
Staph infection around or within hair follicle
Definition of carbuncle
Staph infection of adjacent hair follicles (multiple boils)
Definition of secondary lesions
Excoriation, scales, crust, scar, ulcer, fissure, striae
Definition of excoriation
Loss of epidermis following trauma
Definition of scales
Excoriations in eczema (psoriasis showing silvery scales)
Definition of crust
Rough surface made of serum, blood, bacteria and debris
Exuded through eroded epidermis
eg impetigo
Definition of a scar
New fibrous tissue post wound healing
Atrophic = thinning
Hypertrophic = hyperproliferation within would boundary
Keloidal = hyperproliferation beyond wound boundary
Definition of an ulcer
Loss of epidermis and dermis
Definition of a fissure
Epidermal crack due to excess dryness