Primary and secondary lesion of the skin.

Primary lesion.

• Macule - circumscribed area of skin, up to 1.0 cm, with a change from normal skin color, which is neither raised above nor depressed below the surrounding skin. Many use the term for lesions much greater than 1.0 cm. Term does not include purpura.
  Patch - a flat, circumscribed, discoloration of skin or mucous membrane greater than 1.0 cm in diameter.
• Papule - discrete solid area of skin that is elevated by palpation above the surrounding skin and less than 1 cm in diameter. Variations include accuminate, keratotic, flat-topped, follicular, umbilicated, pedunculated, necrotitic and others.
  Plaque - similar to a papule but greater that 1.0 cm in diameter. Often formed by the confluence or coalescence of papules. Secondary features may include, among others, atrophy, lichenification or hyperkeratosis.
• Nodule - descrete, solid, palpable, round or oval (elipsoidal) lesion of the skin measuring up to 1.0 cm in diameter (or long axis). Applies to processes involving any or all levels of the skin, and is a general term for any mass, benign or malignant.
• Tumor - a term used by some for a "nodule" greater than 1.0 cm in diameter. Applies to processes involving any or all levels of the skin, and is a general term for any mass, benign or malignant.
• Vesicle - a circumscribed fluid-filled lesion less than 1.0 cm in diameter that is usually elevated above the surrounding skin. May be described as solitary, grouped, umbilicated, dyshidrotic, spongiotic, multi-locular or uni-locular.
• Bulla - a circumscribed fluid-filled lesion greater than 1.0 cm in diameter that is usually elevated above the surrounding skin. May attain diameters of several cms and are described as tense, or flacid.
• Pustule - descrete elevated vesicle or bulla of skin, usually small, containing purulent exudate composed of inflammatory leukocytes (pus), with or without cellular debris. May be superficial, deep-seated, follicular, grouped, etc. and may arise secondarily from a vesicle.
• Wheal - an evanescent, round or irregular, often flat-topped elevation of skin with a pale red color, arising from edema in the superficial dermis. May vary from 2-3 mm to 10 or more cm in diameter, with round or arcuate configurations. Should be distinguished from angioedema, a massive edema involving the entire dermis and subcutaneous tissues.

Date: 2015-01-11; view: 821