• Vitiligo is a rare skin disorder, affecting approximately 0.5 to 1% of people worldwide, according to the National Vitiligo Foundation. Most people with vitiligo have few if any other medical problems because of the condition, but possible related conditions include a higher risk of thyroid problems, vitamin B12 deficiency, Addison's disease, alopecia areata, and uvetis. The exact cause of vitiligo remains a mystery, though factors of genetics, immunologic, and the environment contribute. Vitiligo has several notable signs and symptoms.
  
  

Loss of Pigment in Skin

• Vitiligo's most noted symptom is the loss of skin pigmentation. People affected with vitiligo experience a loss of melanin in the skin. Melanin is the substance that gives skin its color. With vitiligo, melanin leaves the skin, leaving behind milky white patches. This is known as depigmentation. The white patches may appear before the age of 10, but most often vitiligo manifests between the ages of 10 and 30.
  
  When the skin loses pigment, the areas affected first are usually those exposed to the sun, such as the hands, arms, and face. Depigmentation occurs most often in one of three different patterns. With generalized depigmentation, skin all over the body loses pigmentation. Segmental depigmentation means that depigmentation appears on one side of the body and not the other. Focal depigmentation is a loss of skin color that is centralized in one of a handful of body parts.
  
  

Mucus Membrane Color Loss

• In addition to skin losing color, in many people affected by vitiligo, the mucus membranes lose color as well. Mucus membranes are the tissue that lines the inside of people's mouths. Those with vitiligo experience depigmentation in these membranes, leaving the inner mouth a similar milky white color as the depigmented spots on the skin.
  
  

Retina Changes

• The retina is a filmy layer at the back of the eye. This layer features light receptors that convert light into signals that travel from the optic nerve to the brain and are interpreted as an image. People with vitiligo experience a change in their retinas that isn't apparent to the naked eye in most cases. The retina of people with vitiligo either loses or changes color. This can be detected by an optical examination.
  
  

Premature Whitening or Graying of Hair

• In more extreme cases of vitiligo, the loss of pigment extends further than just skin. Hair on the scalp, eyelashes, eyebrows, and face can experience premature whitening or graying in these instances. This loss of hair color is usually located around the hair roots, though in some cases it extends past the roots to the whole shaft of the hair.