Vitiligo is a skin pigmentation disorder caused by the progressive destruction of melanocytes.
Melanocytes are the skin cells responsible for producing the skin pigment, melanin. When sunlight penetrates the skin, it activates the melanocytes and the production of melanin. Therefore, melanin protects the skin from damage from sunlight.
However, when the production of melanin falls off, the skin loses its color and turns white.
Vitiligo affects 1 – 2% of the population and it is usually first diagnosed between the ages of 20 and 40 although it has been known to affect children and the elderly. Vitiligo affects male and female equally. It is also affects people of all races although it is more noticeable in dark-skinned people.
Possible Causes of Vitiligo
- Autoimmune attack on healthy melanocytes
- Intrinsic defect in melanocytes
- Increased oxidative stress in the skin
- Nerve damage
- Toxic chemicals especially those containing phenolic compounds
There are a number of theories regarding what causes vitiligo.
Vitiligo first appears as white spots on the skin. While it mostly affects the face, hands and wrists, it can quickly spread to the trunk and lower parts of the body.
The white spots of vitiligo are also commonly seen around the orifices of the body including the mouth, nostrils, eyes, navel and genitals. These spots can also affect the scalp, the inner ear, the choroid of the eyes and mucosal surfaces.
Each vitiligo spot is made up of at least 3 color zones. These include the white zone where most of the melanocytes are lost; the surrounding tan zone where the loss of melanocytes is in progress; and an outer ring of brown zone that forms a border with normal, pigmented skin.
When a vitiligo spot expands, it grows out from the center and changes in both size and shape. Multiple spots soon merge to form large white patches on the skin.