To check the distribution of a skin problem, the doctor may ask a patient to undress completely, even though the patient only noticed an abnormality on a small area of skin. Doctors may also order blood tests or other laboratory tests even if a person seems to have a problem limited only to the skin. Dried blood, pus, or skin fluids on the surface of the skin. A crust can form wherever the skin has been damaged. Loss of part or all of the top surface of the skin.
Erosions occur when infection, pressure, irritation, or temperature has damaged the skin.
Thickened skin that has deep grooves and wrinkles. A flat, discolored spot of any shape, less than 0.4 of an inch in diameter. Freckles, flat moles, port-wine stains, and many rashes are macules. A patch is like a macule, but larger. A solid bump, 0.2 to 0.4 of an inch in diameter, that may be raised.