Flat areas of normal-feeling skin without any pigment appear suddenly or gradually. These areas have a darker border. The edges are well defined but irregular.
Vitiligo most often affects the face, elbows and knees, hands and feet, and genits. It affects both sides of the body equally.
Vitiligo is more noticeable in darker-skinned people because of the contrast of white patches against dark skin.
No other skin changes occur.
Signs and tests
Your health care provider can usually examine your skin to confirm the diagnosis.
Sometimes, a health care provider may use a Wood's light. This is a handheld ultraviolet light that causes the areas of skin with less pigment to glow bright white.
In some cases, a skin biopsy may be needed to rule out other causes of pigment loss. Your doctor may also perform blood tests to check the levels of thyroid or other hormones, and vitamin B12.