Terminology Of Skin Lesions

Primary lesions

Secondary lesions

Scales. An accumulation of excess keratin of the stratum corneum that presents as flaking.
Crusts (scabs). Superficial dried secretions (serum and exudate).
Ulcer. A circumscribed deep defect with loss of all the epidermis and part or all of the dermism they usually heal with scarring.
Erosion. A skin defect with complete or partial loss of the epidermis; they heal without scarring
Fissure. A linear split in the epidermis and dermis
Atrophy. Thinning or loss of epidermis and/or dermis with loss of normal skin markings.
Sclerosis. Thickening of the dermis with induration of subcutaneous tissue; resembles a scar but may arise spontaneously (e.g. scleroderma).
Scar. A healed dermal lesion where normal structures are replaced by fibrous tissue.
Hypertrophic scar. Rises above the skin surface.
Atrophic scar. Settles below the skin surface.
Keloid. Overgrowth of dense fibrous tissue extending beyond the original wound.
Excoriation. Scratch marks causing an erosion or an ulcer (loss of epidermis).
Lichenification. Thickening secondary to chronic scratching or rubbing (in dermatitis).
Callus. Localised hypertrophy of the stratum corneum.
Exfoliation. Loss of epidermal keratin as large scales or sheets.
Keratoderma. Thickening of skin especially stratum corneu

Lichen

keratoderma

Atrophic scar

excoriation (cant stop picking)

Macule	Circumscribed area of altered skin colour (Latin for stain) without elevation <1 cm diameter
Patch	Macule of >1 cm diameter
Papule	Palpable mass on skin surface <1 cm diameter
Plaque	A flat-topped palpable mass >1 cm diameter.
Nodule	A circumscribed, solid palpable mass >1 cm diameter
Wheal	An area of dermal oedema (can be any size), which is pale and compressible.
Angio-oedema	A diffuse area of oedema extending into subcutaneous tissue.
Vesicle	A fluid-filled blister <0.5 cm in diameter
Bulla	A vesicle >0.5 cm diameter
Pustule	A visible collection of pus in the skin <1 cm diameter.
Abscess	A localised collection of pus in a cavity >1 cm diameter
Furuncle	A purulent infected hair follicle; includes:folliculitis (small furuncles)boils (larger furuncles)
Carbuncle	A cluster of boils discharging through several openings
Purpura	A circumscribed deposit of blood >0.5 cm in diameter. May be palpable or non-palpable.
Petechiae	Purpuric lesions <0.5 cm in diameter
Ecchymosis	Larger purpuric lesion
Haematoma	A swelling from gross bleeding.
Telangiectasia	Visible dilatation of small cutaneous blood vessels.
Comedo	A plug of keratin and sebum in a dilated pilosebaceous gland.‘Blackhead’. An open comedo.‘Whitehead’. A closed comedo.
Erythema	Redness of the skin due to increased vascularity.
Milium	Tiny white cyst containing keratin, from occlusion of pilosebaceous gland
Papilloma	Warty projection above the skin surface.