Color changes can be due to any number of causes, including erythema, hemorrhage, or pigment changes. Changes in pigment may be due to increases or decrease in normal pigmentation. They often extend into the dermis, and may be due to inflammatory, neoplastic, or metabolic in origin. Papules P Papules are circumscribed, solid elevations of the skin, up to 1 cm in diameter. The elevation may be due to accumulation of cells, fluid, debris or metabolic deposits and may be follicular or interfollicular in orientation.
Papules often begin as erythematous macules.
A plaque is an elevation of the skin that is usually flat and wider than it is tall. Pustules P Pustules are well circumscribed elevations of the superficial layers of the epidermis. Like papules, they may be follicular or interfollicular in distribution. It must be kept in mind that pustules, due to the thinness of the epidermis are usually transient. What is often observed is a transition from erythematous macules to papules to relatively few pustules to small crusts and scale .