InfoLink: Clinical Advisor
SKIN IQ: Primary and Secondary Lesions
Identifying Primary and Secondary Skin Lesions
Primary skin lesions are present at the onset of a disease. In contrast, secondary skin lesions result from changes over time caused by disease progression, manipulation (scratching, picking, rubbing), or treatment. These 2 types of skin lesions can be differentiated as follows:
- Bulla—a vesicle (see definition below) greater than 5 mm in diameter
- Cyst—an elevated, circumscribed area of the skin filled with liquid or semisolid fluid
- Macule—a flat, circumscribed area; can be brown, red, white, or tan
- Nodule—an elevated, firm, circumscribed, and palpable area greater than 5 mm in diameter; can involve all skin layers
- Papule—an elevated, palpable, firm, circumscribed area generally less than 5 mm in diameter
- Plaque—an elevated, flat-topped, firm, rough, superficial papule greater than 2 cm in diameter; papules can coalesce to form plaques
- Pustule—an elevated, superficial area that is similar to a vesicle but filled with pus
- Vesicle—an elevated, circumscribed, superficial, fluid-filled blister less than 5 mm in diameter
- Wheal—an elevated, irregularly shaped area of cutaneous edema; wheals are solid, transient, and changeable, with a variable diameter; can be red, pale pink, or white.
- Crust—a slightly elevated area of variable size; consists of dried serum, blood, or purulent exudate
- Excoriation—linear scratches that may or may not be denuded
- Lichenification—rough, thickened epidermis; accentuated skin markings caused by rubbing or scratching (eg, chronic eczema and lichen simplex)
- Scale—heaped-up keratinized cells; flakey exfoliation; irregular; thick or thin; dry or oily; variable size; can be white or tan.
© 2005 Lippincott Williams & Wilkins, Inc.
Hess CT. Clinical Guide: Wound Care. 5th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2005.