The term Vitiligo refers to a skin condition presenting as white patches on the body. The patches vary in size. There is no change in texture of the involved skin ie. the skin is not scaly, thickened or red. Furthermore, there are no symptoms eg. itch, burning, stinging or pain.
In Vitiligo patches, there is a complete absence of melanocytes (pigment cells). The cause of Vitiligo is unknown. There are several postulates related to the probable cause. These include:
1. The autoimmune theory:
The body's immune system destroys its own pigment cells.
2. Autocytotoxic theory/self destructive :
The body’s immune system produce toxic metabolites that destroy the pigment cells
3. Neurogenic hypothesis:
Nerve endings release substances which destroy pigment cells.
Vitiligo is thought to be an inherited disease. There is usually a positive family history in most patients. The Koebner phenomenon may sometimes be seen in Vitiligo. In this situation, white patches develop at sites of injury. Usually pigment cells in the upper part of the skin are involved (epidermis). Occasionally, however, pigment cells in the deeper part of the skin, around the hair follicles (roots of the hair), may be involved, in which case emerging hairs appear white.
Any part of the body may be affected in Vitiligo. The common sites of involvement include the trunk, lips, tips of the fingers and toes and genitalia. The lesions may be small or may become confluent to form large patches.
It is important to understand that this is a very difficult condition. The natural course and treatment success is unpredictable. The therapeutic options include the following:
Photosensitisers: Topical psoralens (applied form of the medication) can be used to make the skin sensitive to sunlight.
-Oral trisoralens followed by sun exposure. Tablets are taken followed by sun exposure
-Topical khellin photosensitiser followed by exposure to sunlight.
Topical immunomodulators eg. Tacrolimus
Topical Vitamin D analogues
Oral pulse steroids eg. Betamethasone 2 x week.
Phototherapy- Narrowband UVB/ PUVA therapy
Bleaching –applies to widespread vitiligo. The remaining normal skin may be treated with monobenzyl ether of hydroquinone.
Surgical therapies for stable vitiligo- this applies to techniques where normal pigmented skin is transplanted to the vitiligo areas. These include :
- punch skin grafting
- suction blister grafting
- Autologous cultured epidermal cell grafting
- Non-cultured melanocyte rich epidermal cell suspensions
- Excimer laser therapy