Vitiligo: Causes, Symptoms and Treatments written by: akshat.singh Vitiligo: Causes, Symptoms and Treatments
Vitiligo is a skin disorder characterized by discoloration of patches of skin caused by loss of pigment carrying cells in the epidermis known as melanocytes. Melanocytes are responsible for the production of the pigment melanin which imparts the color to the skin. As a result the patches of skin become pale and usually have sharp margins. In some cases the hair on the affected skin also becomes white. The disorder also affects mucous membranes such as those inside the nose and mouth. Generally both the frontal and dorsal regions of the body are equally affected.
The patches generally begin to occur on skin that is exposed to the sun and on the skin at the extremities of the body. The effect is more pronounced near orifices such as mouth, eyes, genitals, moles etc.
About 2% of the global population is affected by this disorder. However some communities may have a larger likelihood of being affected due to gene localization. All races and both sexes are equally likely to suffer from vitiligo. Although the effect is more pronounced in people with darker skin due to the contrast created by the patches.
In about half of the cases it develops early on in the life, generally before age 20. However the symptoms almost always show up before 40. Vitiligo is neither contagious nor life-threatening. However it causes psychological stress in patients and may lead them to develop low self-esteem and serious depression.
Vitiligo is a multifactorial disease which is affected by both genetic susceptibility and environmental conditions. There are two major pathways through which skin discoloration takes place. One is gene variation which causes failure of melanin synthesis in melanocytes due to the absence of production of the protein tyrosinase which is the main enzyme responsible for the catalysis of melanin biosynthesis. The other major pathway is the destruction of melanocytes either by themselves, or by the attack of the immune system. Although many causes have been advocated for this disorder, some studies have provided more evidence for it to be an autoimmune disorder.
Vitiligo is classified into two categories based on symptoms and possible causes. The more common non-segmental vitiligo which appears in symmetrical patterns is often identified as an autoimmune disorder. The immune system identifies the melanocytes as foreign bodies and targets them. The other type of vitiligo, segmental vitiligo is believed to be caused by gene variations associated with bio synthesis of melanin and tends to affect areas associated with the central nervous system.
In most of the cases, people suffering from vitiligo have been found to be also affected by autoimmune and inflammatory diseases such as autoimmune thyroid disease, type 1 diabetes, rheumatoid arthritis, scleroderma, Addison’s disease. Alopecia Areata is an autoimmune disease that causes hair to fall out in round patches. People with a family history of vitiligo are more likely to suffer from it or when people in their family have been known to get grey hair prematurely.
Some studies have also demonstrated people with regular long duration to sun without any UV protection, and people with a history of skin cancer to be more susceptible to the skin disorder. Sunburn has also been touted as a possible cause, but there isn’t enough positive evidence to support this. Vitiligo may also be caused by trigger events such as sudden stress or contact with toxic, industrial chemicals. Newer studies have suggested gluten consumption, and preliminary evidences have been provided for the same.
The major symptom of vitiligo is the appearance of pale patches of skin. These matches generally begin at the extremities of the body or at areas exposed to the sun such as hands, feet, face, lips or the genitals.
· Patches of pale skin
· Premature graying of the hair on your scalp, facial hair or hair in the pubic region
· Discoloration in mucous membranes( inside of mouth and nose) particularly noticeable in people with dark skin
· Loss of or change in color of the inner eye(retina) due to change in melanin concentration leading to people with dark eye color going to light eye color
Vitiligo typically starts at early age, often before the age of 20. However the symptoms almost always occur before the age of 40.
Vitiligo is categorized into two major types:
· Segmental. Begins at an early age. Loss of pigment on one segment of the body, such as one arm, one leg. Premature graying of hair. Pigmentation occurs for about one year and then stops.
· Non-Segmental. Pigment loss begins at a rapid pace and occurs in cycles. Often starts at hands, feet, face. Pigment loss on both segments of body such as both hands, both feet. Occurs throughout life with skin patches getting larger and larger.
Further subtypes include:
· Generalized. Most common type. Scattered patches on whole body.
· Universal. Most pigment on the body is gone.
· Localized. One or only a few areas of the body.
It is difficult to predict the extent of pigment loss. Sometimes the discoloration may stop, only to reappear later in life. In most cases often the pigmentation spreads to the whole body. In rare cases, the skin gets its pigment back.
Many treatments are available for vitiligo that mainly try to restore skin color or help to merge the skin patches with the rest of the skin tone. However the results vary from person to person and some people may need a combination of treatments to achieve the optimum results.
There are no drugs that can reverse the main cause of vitiligo: loss of melanocytes. However they can help restore skin tone in conjunction with light therapy.
· Creams that reduce inflammation. Help restore skin color if applied during early stages. Results may take months to appear. Easy to use. But it comes with side effects, such as thinning of the skin.
· Medications that alter the immune system. Effective for localized vitiligo in conjunction with UVB light treatment. But has possible dangers of causing skin cancer.
· Psoralen plus light therapy. Application of plant extract psolaren on affected skin or ingestion combined with exposure to light therapy. Better results as compared to medication or light therapy alone, but treatment needs to be continued for a long duration.
· Depigmentation. Only suitable for people with universal vitiligo. Depigmenting agent is applied to unaffected areas so that they blend in with the rest of the skin. Side effects include itching, swelling, and extreme sensitivity to sunlight.
· Skin Grafting. The doctor takes skin grafts from unaffected areas and transplants them onto discolored areas. Suitable for people with localized vitiligo.
· Blister Grafting. Blisters are produced on the unaffected skin, and then the top of these blisters are removed and transplanted onto the affected skin.
· Tattooing. Most suitable for darker skinned people with vitiligo around the lips. Pigment is imparted to the affected skin through surgical means.