Flashcards in Dermatology - Clinical skills Deck (41):
What are the 4 aspects of skin examination?
What are the key features of inspecting a skin lesion?
This should involve a general observation, noting the site and number of lesions. If lesions are multiple then note the pattern of their distribution and configuration.
Terms that can be used to describe distribution include generalised, widespread, localised, flexural, extensor, pressure areas, photosensitive or Koebner phenomenon.
Terms that are used to describe configuration are discrete, confluent, linear, target, annular and discoid.
What does a generalised lesion mean?
A lesion all over the body
What is a widespread lesion?
Extensive (covering a sizeable portion, but not all, of the body)
What is a localised lesion?
Restricted to one area of skin only
What is a flexural rash/ lesion?
Located on the body folds i.e. groin, neck, behind the ears, popliteal and anticubital fossa. This is opposed to extensor rashes which are found on the knees, elbows and shins.
What are the pressure areas?
Sacrum, buttocks, ankles and heels.
What is a photosensitive rash?
A rash affecting sun exposed areas such as the face, neck and back of hands.
What is the Koebner phenomenon?
A linear eruption arising at the site of trauma.
What is a discoid lesion?
Individual lesions separated from one another.
What is a confluent lesion?
Lesions merging together
What is a target lesion?
Concentric rings (like a dartboard) - seen in erythema multiforme.
What is an annular lesion?
A lesion that resembles a ring or circle - e.g. tinea corporis (ring worm)
What is a discoid lesion?
Coin shaped/ round lesion - e.g. discoid eczema
How should one describe a lesion?
- Size (widest diameter), Shape
- Associated secondary change
- Morphology, Margin (border)
If the lesion is pigmented remember ABCD (the presence of any of these features increases the likelihood of malignancy)
- Asymmetry (lack of mirror image in any of the four quadrants)
- Irregular Border
- Two or more Colours within the lesion
- Diameter >6cm
What does erythema mean?
Redness (due to inflammation and vasodilatation) which blanches on pressure - e.g. palmar erythema
What is purpura?
Red or purple colour (due to bleeding into the skin or mucous membrane) which does not blanch on pressure - petechiae (small pinpoint macules) and ecchymoses (larger bruise like patches)
- purpuric rash due to low platelets (i.e. thrombocytopaenia) is not palpable
- purpuric rash due to vasculitis is palpable (due to vessel inflammation)
What is hypopigmentation?
Areas of paler skin - e.g. pityriasis versicolor (a superficial fungus infection)
What is depigmentation?
White skin due to absence of pigmentation - e.g. vitiligo (loss of skin melanocytes)
What is hyperpigmentation?
Darker skin which may be due to various causes (e.g. post inflammatory) - e.g. Melasma (increased melanin pigmentation)
What is a macule?
This is a descriptive term relating to the primary lesion. It means a flattened area of altered colour - e.g. freckles.
What is a patch?
A larger flattened area of altered colour - e.g. vascular malformation (naevus flammeus/ port wine stain)
What is a papule?
A solid raised lesion <0.5cm in diameter - e.g. xanthomata
What is a nodule?
A solid raised lesion >0.5cm in diameter with a deeper component - e.g. pyogenic granuloma
What is a plaque?
Type of primary skin lesion
A palpable scaling raised lesion >0.5cm in diameter - e.g psoriasis
Raised, clear fluid filled lesion <0.5cm in diameter
Raised, clear fluid filled lesion >0.5cm in diameter - e.g. reaction to insect bites
Term to describe a primary lesion. Pus containing lesion <0.5cm in diameter - e.g. acne
Localised accumulation of pus in the dermis or subcutaneous tissue
Transient raised lesion due to dermal oedema - e.g. urticaria
Staphylococcal infection around or within a hair follicle
Staphylococcal infection of adjacent hair follicle
What are secondary lesions?
Lesions that involve from the primary lesion
Loss of epidermis following trauma - e.g. itching in eczema
Well defined roughening of the skin with accentuation of skin margins - e.g. lichenification due to chronic rubbing in eczema
Flakes of stratum corneum
What are crusts?
Rough surface consisting of dried serum, blood, bacteria and cellular debris that has exuded through an eroded epidermis (e.g. from a burst blister) - e.g. impetigo
What is a scar?
New fibrous tissue which occurs post wound healing, and may be atrophic (thinning), hypertrophic (hyperproliferation within wound boundary) or keloidal (hyperproliferation beyond wound boundary).
What is an ulcer?
Loss of epidermis and dermis
What is a fissure?
An epidermal crack often due to excess dryness