What is Vitiligo?
Vitiligo is a common condition where white patches develop on the skin. It is due to loss of pigment from affected areas of the skin. There are usually no other symptoms but the appearance of the skin can cause distress. The affected areas of skin can be covered by skin camouflage creams. Also, treatment has improved in recent years and in some cases the pigment can be restored.
Understanding the skin
To understand the cause of vitiligo, it is useful to have a basic understanding of the skin. The skin has two layers the epidermis and the dermis. Beneath the dermis is a layer of fat, and then the deeper structures such as muscles, tendons, etc.
The epidermis has three main types of cell.
Basal cells: These are the bottom layer of cells in the epidermis.
Keratinocytes: These cells are in layers above the basal layer. They make a substance called keratin which is a hard 'waxy' material. Keratinocytes are constantly dividing and a certain number are dying at any given time. The top 'horny' layer of the epidermis is made of dead keratinocytes which contain keratin. The top of the skin is constantly being shed and replaced by new dead cells which contain keratin.
Melanocytes: These cells are dotted about at the bottom of the epidermis. They make a pigment called melanin. The melanin is passed to the nearby skin cells which colours the skin and protects them from the sun's rays. Melanin causes the skin to tan in fair skinned people. Dark skinned people have more active melanocytes. The melanocytes are stimulated when exposed to sunlight to make more melanin.
What causes it?
Vitiligo is a condition where pale white patches develop on the skin. It is due to a lack of pigment (colour) in the affected areas of skin. Vitiligo does not make you feel ill. However, the appearance of vitiligo can be distressing. This is particularly so for darker skinned people where white patches are more noticeable.
Areas of skin with patches of vitiligo have no or very few melanocytes. Therefore melanin cannot be made, and the colour of the skin is lost. It is not known why the melanocytes go from affected areas of skin. They may be destroyed by the immune system or 'self-destruct' for reasons not yet known. There is some genetic factor involved and vitiligo may 'run in the family'. About 1 in 3 affected people have some other family member who is also affected. However, 2 in 3 affected people do not have other family members affected so it is not just an inherited problem.
Who gets vitiligo?
About 1 in 100 people develop vitiligo. Men and women are equally affected. It can develop at any age. However, it begins before the age of 20 in about half of cases. Vitiligo is not infectious and you cannot 'catch' it from affected people.
What areas of skin are affected with vitiligo?
Any area of skin can be affected. However, the most common sites involved are the face, neck, and scalp. Other common sites include the backs of hands, front of knees, and elbows. In the areas of the scalp that are affected, the hair too is affected. So, you may develop patches of hair with no colour - so the affected patches of hair look grey or white.
How does vitiligo progress?
Small areas of milky white skin usually develop first. The contrast between the vitiligo skin and normal skin varies. In fair skinned people it may only be noticeable in summer when normal skin tans. The contrast is more noticeable in darker skinned people.
The course and severity of vitiligo varies from person to person. Sometimes a few small patches develop slowly and progress no further. Sometimes a number of patches develop quite quickly and then remain static for months or years without changing. However, it is quite common for the white patches to gradually become bigger and for more patches to appear on other parts of the body. Large areas of the skin may eventually be affected.
There is no way of predicting how much of the skin will eventually be affected when the first patch develops. The white patches are usually permanent. Rarely, some patches of vitiligo may re-pigment and return to normal.
What are the symptoms of vitiligo?
People with vitiligo are normally well. Vitiligo is not sore or itchy. However, the appearance of the skin can be distressing, particularly if the face or hands are affected.
Sunburn is a risk. There is no natural protection from the sun in affected areas of skin. Vitiligo skin burns much more easily than normal skin if exposed to sunlight.
Surgical therapies are very expensive and demand rigorous commitment of self-care. Moreover, they are viewed as experimental because their effectiveness and side effects remain to be fully defined. These include :
Autologus skin grafts
Skin grafts using blisters
Micro pigmentation (tattooing)
Autologous melanocyte transplants
Autologous Skin Grafts
In an autologous (use of a person's own tissues) skin graft, the doctor removes skin from one area of a patient's body and attaches it to another area. This type of skin grafting is sometimes used for patients with small patches of vitiligo. The doctor removes sections of the normal, pigmented skin (donor sites) and places them on the depigmented areas (recipient sites). There are several possible complications of autologous skin grafting. Infections may occur at the donor or recipient sites. The recipient and donor sites may develop scarring, a cobblestone appearance, or a spotty pigmentation, or may fail to repigment at all. Treatment with grafting takes time and is costly, and most people find it neither acceptable nor affordable.
Skin Grafts Using Blisters
In this procedure, the doctor creates blisters on the patient's pigmented skin by using heat, suction, or freezing cold. The tops of the blisters are then cut out and transplanted to a depigmented skin area. The risks of blister grafting include the development of a cobblestone appearance, scarring, and lack of repigmentation. However, there is less risk of scarring with this procedure than with other types of grafting.
Tattooing implants pigment into the skin with a special surgical instrument. This procedure works best for the lip area, particularly in people with dark skin; however, it is difficult for the doctor to match perfectly the color of the skin of the surrounding area. Tattooing tends to fade over time. In addition, tattooing of the lips may lead to episodes of blister outbreaks caused by the herpes simplex virus.
Autologous Melanocyte Transplants
In this procedure, the doctor takes a sample of the patient's normal pigmented skin and places it in a laboratory dish containing a special cell culture solution to grow melanocytes. When the melanocytes in the culture solution have multiplied, the doctor transplants them to the patient's depigmented skin patches. This procedure is currently experimental and is impractical for the routine care of people with vitiligo.