Dermatology Terminology

• Macules are flat lesions defined by an area of changed color (i.e., a blanchable erythema).
• Papules are raised, solid lesions <5>
• Plaques are lesions >5 mm in diameter with a flat, plateau-like surface.
• Nodules are lesions >5 mm in diameter with a more rounded configuration.
• Wheals (urticaria, hives) are papules or plaques that are pale pink and may appear annular (ringlike) as they enlarge; classic (nonvasculitic) wheals are transient, lasting only 24 to 48 h in any defined area.
• Vesicles (<5>5 mm) are circumscribed, elevated lesions containing fluid.
• Pustules are raised lesions containing purulent exudate; vesicular processes such as varicella or herpes simplex may evolve to pustules.
• Nonpalpable purpura is a flat lesion that is due to bleeding into the skin.
• If <3>
• If >3 mm, they are termed ecchymoses.
• Palpable purpura is a raised lesion that is due to inflammation of the vessel wall (vasculitis) with subsequent hemorrhage.

Category: Dermatology Notes