19/06/2022
Definitions
• : a circumscribed flat area of skin of ≤ 1 cm diameter that appears different from the skin surrounding it, usually because of
different colour
• : the same as a macule but larger
• Papule: a discrete elevation of skin of ≤ 1 cm diameter
• : similar to a papule but having significant depth (into dermis or even subcutaneous layer) and usually > 1 cm in diameter
• : a raised area of skin with a flat top, > 1 cm in diameter
• and bulla: a small (≤ 1 cm) and a larger (> 1 cm in diameter) fluid-filled blister, respectively
• : a visible accumulation of pus in a blister
Other terms
• : a localised collection of pus in a cavity
• : an area of thin, translucent skin caused by loss of epidermis, dermis or subcutaneous fat, e.g. secondary to excess topical
corticosteroids
• : a linear or curvilinear papule, caused by a burrowing scabies mite
• : a plug of keratin and sebum in a dilated pilosebaceous or***ce
• : dried exudate of blood or serous fluid
• : an area of skin denuded by complete or partial loss of the epidermis
• : a linear ulcer or erosion resulting from scratching
• : a slit-shaped deep ulcer, e.g. in irritant dermatitis of the hands
• , purpura and ecchymosis: petechiae are pinhead-sized, flat macules of extravascular blood in the dermis; purpura are
larger and may be palpable; ecchymosis (‘bruise’) is the term used to describe bleeding that involves deeper structures
• : a flake arising from the stratum corneum. Any condition with a thickened stratum corneum, i.e. hyperkeratosis, can cause
scaling. An immature thickened and cohesive stratum corneum, e.g. as in psoriasis or Bowen’s disease, gives characteristic
optical and physical properties that cause a different scale from that due to a thickened, but otherwise normal, stratum corneum
• : replacement of normal structures by fibrous tissue at the site of an injury
• : a cavity or channel that permits the escape of pus or fluid
• : a linear, atrophic, pink, purple or white band caused by connective tissue changes
• : visible dilatation of small cutaneous blood vessels
• : an area from which the epidermis and at least the upper part of the dermis have been lost
• : an evanescent discrete area of dermal oedema, often centrally white due to masking of local blood supply by fluid; weals can
be papules, macules, patches and plaques