Alternate Names: Hypomelanosis; Mottled skin; Loss of skin color in places; Patchy loss of skin color; Hypopigmentation

Considerations: Melanin is a pigment produced in the skin cells that causes skin coloration. An amino acid, tyrosine, is converted to melanin through a series of complex chemical steps in the skin cells. This process may be affected by heredity, heat, trauma, solar or ionizing radiation, heavy metals, and other factors. Pigment production and distribution in the body is regulated in part by hormones. Changes in any of these factors can result in hyperpigmentation (increase in pigment production), hypopigmentation (decrease in pigment production), or both. The changes may be temporary or permanent. Pigment changes can be primary (existing as a separate disorder) or secondary to other disorders.

A person’s degree of skin pigmentation determines, to some extent, the various dermatological diseases to which a person may be susceptible. Lighter-skinned people are more sensitive to sun exposure and damage and the subsequent development of skin cancer (basal cell carcinoma, squamous cell carcinoma and malignant melanoma). Excessive sun exposure is a risk factor even for darker-skinned people.

Generally, pigmentary changes are cosmetic and do not affect physical health. However, psychological stress can occur because of pigmentary changes. Some pigment changes may indicate a risk for other disorders.

Common Causes:

• sunburn or sun tan
• uneven application of sunscreen resulting in areas of burn, tan, and no tan
• cuts, scrapes, wounds, insect bites and minor skin infections
  • skin discoloration during the healing process
  • with time, the skin coloring generally returns
  • In darker-skinned people skin damage may cause permanent hyperpigmentation
• moles (nevi) and bathing trunk nevi or giant nevi
• malignant melanoma
• cafe-au-lait spots
• Mongolian blue spots
• vitiligo
• pityriasis alba (small circular pale spots on a child’s face, usually the cheeks, often noticeable in the summertime when the skin is tanned)
• tinea versicolor
• erythrasma
• mask of pregnancy (also called chloasma or melasma, a dark brown discoloration of the cheeks and the forehead of pregnant women or those using oral contraceptives)
• photosensitivity as a reaction to medications or certain drugs
• radiation therapy

Home Care: Spontaneous return of normal skin color may occur in some cases. Patience is the most effective measure for loss of skin color.

Exposure to sun or ultraviolet (UV) light, especially after sensitization with an oral medication (psoralens), may increase pigmentation. This is effective for about 60% of hypopigmentation lesions if done 2 to 3 times a week for 2 or 3 years, but it may have side effects and may increase the risk for skin cancer.

Lotions that bleach or lighten the skin, such as benoquine or hydroquinone lotions, may be used to reduce hyperpigmented skin or to even the skin tone where hypopigmented areas are large or conspicuous.

Selsun blue or Tolnaftate (Tinactin) lotion can help in treating tinea versicolor. Apply as directed to the affected area daily until the lesions disappear. Unfortunately, tinea versicolor often returns no matter what type of treatment is used.

Cosmetics or skin dyes may be used to disguise pigmentary changes. Make-up can help hide mottled skin but will not cure the underlying problem.

Avoid excessive sun exposure and use sun block because hypopigmented skin sunburns easily.

Call If:

• the skin is mottled at the elbows and knees, or all over, and is pale, cool, and clammy. This may indicate hypovolemic shock, which requires immediate medical attention.
• there is any change in skin pigmentation that occurs without an obvious cause and is persistent.
• you notice a new mole or other growth, or an existing one has changed color, size, or appearance.

What To Expect: The medical history will be obtained and a physical examination performed.

Medical history questions documenting patchy skin color in detail may include:

• time pattern
  • When did it develop?
  • Did it develop slowly or suddenly?
  • Is it getting worse? How fast?
• quality
  • Is it a loss of pigment?
  • Is it a problem with the blood vessels?
  • What color is the affected area?
  • What is the normal skin color?
• location
  • Exactly where is the skin color changed?
  • Is it in more than one location?
• aggravating factors
  • Have you had any trauma to the skin (including sunburn or frequent sun tans)?
  • Are you pregnant?
  • What medications do you take?
  • What medical treatments have you had?
• other
  • What other symptoms are also present?

• scrapings of skin lesions
• Wood’s lamp (ultraviolet light) examination of the skin