Vitiligo: (vit·i·li·go) Vitiligo is a skin condition of white patches resulting from loss of pigment. Any part of the body may be affected. Melanin, the pigment that determines color of skin, hair, and eyes, is produced in cells called melanocytes. If these cells die or cannot form melanin, the skin becomes lighter or completely white. Affected skin is particularly sensitive to sunlight.
The usual type of vitiligo is called ‘Vitiligo Vulgaris’ (means: common vitiligo). Variant types include linear, segmental, trichrome and inflammatory vitiligo.
This disease affects an estimated 1% of the world’s population. It affects individuals of all ethnic origins and both sexes, but is much more easily noticed on darker skin as areas that fail to tan. It is hereditary in one third of those affected. Vitiligo often starts on the hands, feet or face, and frequently pigment loss is progressive. Half the patients first notice vitiligo before 20 years of age. It often appears in an area of minor injury or sunburn.
The diagnosis of vitiligo is usually straightforward, and no special testing is needed. While vitiligo is a cosmetic problem and does not affect the health directly, it is disfiguring and may be psychologically traumatic. The condition cannot be cured at present, but treatments are available that may be very helpful. Medical treatments target the immune system, and try to reverse the destruction. Surgical treatments are less commonly done, and transplant healthy melanocytes from other areas. Both treatments may be difficult and prolonged.
Topical Steroid Therapy
Steroids may be helpful in repigmenting the skin (returning the color to white patches), particularly if started early in the disease. Corticosteroids are a group of drugs similar to the hormones produced by the adrenal glands (such as cortisone).
Doctors often prescribe a mild topical corticosteroid cream for children under 10 years old and a stronger one for adults. Patients must apply the cream to the white patches on their skin for at least 3 months before seeing any results. It is the simplest and safest treatment but not as effective as psoralen photochemotherapy (see below). The doctor will closely monitor the patient for side effects such as skin shrinkage and skin striae (streaks or lines on the skin).
Psoralen photochemotherapy (psoralen and ultraviolet A therapy, or PUVA) is probably the most beneficial treatment for vitiligo available in the United States. The goal of PUVA therapy is to repigment the white patches. However, it is time-consuming and care must be taken to avoid side effects, which can sometimes be severe. Psoralens are drugs that contain chemicals that react with ultraviolet light to cause darkening of the skin.
The treatment involves taking psoralen by mouth (orally) or applying it to the skin (topically). This is followed by carefully timed exposure to ultraviolet A (UVA) light from a special lamp or to sunlight. Patients usually receive treatments in their doctors’ offices so they can be carefully watched for any side effects. Patients must minimize exposure to sunlight at other times.
Topical Psoralen Photochemotherapy
Topical psoralen photochemotherapy often is used for people with a small number of depigmented patches (affecting less than 20 percent of the body). It is also used for children 2 years old and older who have localized patches of vitiligo. Treatments are done in a doctor’s office under artificial UVA light once or twice a week.
The doctor or nurse applies a thin coat of psoralen to the patient’s depigmented patches about 30 minutes before UVA light exposure. The patient is then exposed to an amount of UVA light that turns the affected area pink. The doctor usually increases the dose of UVA light slowly over many weeks.
Eventually, the pink areas fade and a more normal skin color appears. After each treatment, the patient washes his or her skin with soap and water and applies a sunscreen before leaving the doctor’s office.
There are two major potential side effects of topical PUVA therapy:
(1) severe sunburn and blistering and
(2) too much repigmentation or darkening of the treated patches or the normal skin surrounding the vitiligo (hyperpigmentation). Patients can minimize their chances of sunburn if they avoid exposure to direct sunlight after each treatment.
Hyperpigmentation is usually a temporary problem and eventually disappears when treatment is stopped.
Oral Psoralen Photochemotherapy
Oral PUVA therapy is used for people with more extensive vitiligo (affecting greater than 20 percent of the body) or for people who do not respond to topical PUVA therapy. Oral psoralen is not recommended for children under 10 years of age because of an increased risk of damage to the eyes, such as cataracts.
For oral PUVA therapy, the patient takes a prescribed dose of psoralen by mouth about 2 hours before exposure to artificial UVA light or sunlight. The doctor adjusts the dose of light until the skin areas being treated become pink. Treatments are usually given two or three times a week, but never 2 days in a row.
For patients who cannot go to a PUVA facility, the doctor may prescribe psoralen to be used with natural sunlight exposure. The doctor will give the patient careful instructions on carrying out treatment at home and monitor the patient during scheduled checkups.
Known side effects of oral psoralen include sunburn, nausea and vomiting, itching, abnormal hair growth, and hyperpigmentation. Oral psoralen photochemotherapy may increase the risk of skin cancer.
To avoid sunburn and reduce the risk of skin cancer, patients undergoing oral PUVA therapy should apply sunscreen and avoid direct sunlight for 24 to 48 hours after each treatment. Patients should also wear protective UVA sunglasses for 18 to 24 hours after each treatment to avoid eye damage, particularly cataracts.
Depigmentation involves fading the rest of the skin on the body to match the already white areas. For people who have vitiligo on more than 50 percent of their bodies, depigmentation may be the best treatment option. Patients apply the drug monobenzylether of hydroquinone (monobenzone or Benoquin*) twice a day to pigmented areas until they match the already depigmented areas. Patients must avoid direct skin-to-skin contact with other people for at least 2 hours after applying the drug.
The major side effect of depigmentation therapy is inflammation (redness and swelling) of the skin. Patients may experience itching, dry skin, or abnormal darkening of the membrane that covers the white of the eye. Depigmentation is permanent and cannot be reversed. In addition, a person who undergoes depigmentation will always be abnormally sensitive to sunlight.