Silvery, flaky areas of dead skin build up on the surface of the plaques before being shed. Patches usually appear as smooth inflamed areas without a scaly surface. Plaques are usually small, no more than 1cm in diameter. Psoriasis is a non-contagious common skin condition that causes rapid skin cell reproduction resulting in red, dry patches of thickened skin. The most common form, plaque psoriasis, appears as raised, red patches or lesions covered with a silvery white buildup of dead skin cells, called scale. The rash of Plaque psoriasis typically appears as raised areas of inflamed skin covered with silvery white scaly skin.
Environmental, genetic, and immunologic factors appear to play a role. Plaque psoriasis is raised, roughened, and covered with white or silver scale with underlying erythema. Dermatologic: Most commonly, scaling erythematous macules, papules, and plaques; area of skin involvement varies with the form of psoriasis. Erythrocyte sedimentation rate: Usually normal, except in pustular and erythrodermic psoriasis, where it may be elevated along with the white blood cell count.