Table 2.
Basic descriptive terms for cutaneous lesions2
| Term | Definition |
|---|---|
| Macule | Flat, circumscribed, non-palpable lesion that differs in colour from the surrounding skin; it can be any colour or shape (≤1 cm); referred to as a patch if >1 cm |
| Papule | Elevated, solid, palpable lesion that is ≤1 cm in diameter |
| Plaque | Circumscribed, palpable lesion >1 cm in diameter; most plaques are elevated; plaques may result from a coalescence of papules |
| Nodule | Elevated, solid, palpable lesion >1 cm usually located primarily in the dermis or subcutis; the greatest portion of the lesion may be exophytic or beneath the skin surface |
| Weal | Transient elevation of the skin caused by dermal oedema, often pale centrally with an erythematous rim |
| Vesicle | Circumscribed lesion ≤1 cm in diameter that contains liquid (clear, serous or haemorrhagic) |
| Bulla | Circumscribed lesion >1 cm in diameter that contains liquid (clear, serous or haemorrhagic) |
| Pustule | Circumscribed lesion that contains pus |
| Scale | Visible accumulation of keratin, forming a flat plate or flake |
| Crust | Dried serum, blood or pus on the surface of the skin |
| Erosion | Loss of either a portion of or the entire epidermis |
| Excoriation | Loss of the epidermis and a portion of the dermis caused by scratching or an exogenous injury |
| Ulcer | Full-thickness loss of the epidermis plus at least a portion of the dermis; it may extend into the subcutaneous tissue |