Vitiligo is an acquired pigmentary disorder of the skin. It is characterized by circumscribed depigmented sections of skin. The cause of vitiligo is unknown and it is related to both genetic and nongenetic factors.
Vitiligo is signified by acquired white or hypopigmented macules or patches. Affected areas are generally well differentiated, and are spherical, oblong, or linear in shape. Borders can be convex . Generally, the lesions grow centrifugally as the time passes at an erratic rate. Size of the lesions can differ from millimeters to centimeters. In the beginning, lesions appear very often on the hands, forearms, feet, and face. Perioral and periocular areas are most favorable sites.
Vitiligo lesions may be seen only in an area or many areas all over the body, but commonly it widely affects the entire body. In such cases, the macules are generally seen on both sides of the trunk, either evenly or unevenly aligned.
Vitiligo commonly affects the face, neck, and scalp. Mostly, it affects the areas that are subjected to recurrent trauma. Common involvements are bony prominences, extensor surface of forearm, ventral aspects of wrists, dorsal side of hands, and digital phalanges.
Mucous membranes are involved in cases of generalized vitiligo. It generally develops surrounding the body orifices like the lips, genitals, gingiva, areolas, and nipples.
Depigmented body hair (leukotrichia) can be seen in vitiliginous macules. Vitiligo affecting the scalp develops as a limited area of white or gray hair, but complete depigmentation of entire scalp hair may take place. Scalp is involved very frequently, followed by the eyebrows, axillary hair, and pubic hair.
Diagnosis of vitiligo usually is made with the help of clinical findings, but sometimes biopsy is beneficial in individualization of vitiligo from various hypopigmentary disorders.
Vitiligo is sometimes seen along with various autoimmune diseases like thyroid disease, diabetes mellitus, pernicious anemia, Addison disease, and alopecia areata. Individuals should have knowledge about manifestations of these diseases. In case the disease is manifested than necessary tests should be done . Vitiligo lesions are analyzed with the help of a Wood lamp.
No drug can stop the process of vitiligo, but some drugs when used individually, or along with light therapy, may be helpful in improving the skin's appearance.
Generally, limited vitiligo involving the face and trunk in children of recent onset is very receptive to treatment. Wide-spread disease in adults and disease affecting the hands and feet is resistant to therapy.
The incidence worldwide is less than 1% . Around 30% of the cases are seen within a group of members in a family. Appearance of the vitiligo is independent of the age, although the onset is usually observed in persons aged 10-30 years. In most of the cases, the person suffers from vitiligo at early age in life.
Vitiligo can be caused by both genetic and non-genetic factors. Even though the actual cause remains unknown, commonly considered factors are that there are no functional melanocytes left in the affected skin and there is damage of histochemically identified melanocytes, leading to their destruction. Theories regarding destruction of melanocytes include the following:
Autoimmune destruction of melanocytes
The autoimmune theory  suggests changes in humoral and cellular immunity in the devastation of melanocytes of vitiligo. The most assuring data of an autoimmune involvement is the existence of circulating antibodies in persons suffering from vitiligo . Substantial data points towards link between cellular immunity and vitiligo.
Intrinsic defect of melanocytes
Vitiligo melanocytes might have an intrinsic defect causing death of melanocyte. These melanocytes exhibit different abnormalities like unusual, harsh endoplasmic reticulum and inadequate synthesis and transformation of melanocytes.
Disruption in oxidant-antioxidant mechanism in vitiligo
Studies suggest that piling up of free radicals lethal to melanocytes results in their devastation. Current investigations are deployed to figure out the action of oxidative stress by calculating the levels of antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) in the affected as well as the unaffected skin of patients suffering from vitiligo and in the skin of totally unaffected control persons. It was proved that oxidative stress is raised in vitiligo, as determined by increased levels of SOD and decreased levels of CAT in the skin of people suffering from vitiligo .
Case reports portray that patients suffering from an injury to nerve along with having vitiligo, are also suffering from hypopigmentation or depigmentation in those denervated regions. In addition, segmental vitiligo regularly develops in a dermatomal pattern, which indicates that some chemical mediators are liberated from nerve endings affecting the melanin production. Additionally, sweating and vasoconstriction are raised in depigmented patches of vitiligo, suggesting high adrenergic activity. Ultimately, increased excretion of homovanillic acid and vanillylmandelic acid in urine has been recorded in patients suffering from vitiligo. This can be a basic or trivial episode .
Genetics of vitiligo
Vitiligo is characterized by partial penetrance, many sensitive areas, and genetic heterogeneity . Vitiligo caused due to inheritance can be due to involvement of genes related to the biosynthesis of melanin, reaction to oxidative stress, and control of autoimmunity .
There is no way to prevent vitiligo, but using sunscreens with a minimum sun protection factor (SPF) of 15 to protect the skin from the sun is always a healthy decision.
Vitiligo is a condition that causes depigmentation of segments of the skin. Being a genetic disorder there is no way of preventing this disease; it is advised to start the treatment as early as possible. As the disease is associated with various other autoimmune diseases, care must be taken to diagnose and treat them too. Emotional support is another important part of vitiligo therapy as the skin changes caused by vitiligo can affect people emotionally and socially.
Even in today’s world due to unawareness people feel that vitiligo can also spread due to close contact but that is not true, vitiligo is not a communicable disease. It does not cause any disability and the patient is fit for any type of work. Now due to progress in cosmetic industry there are many local applications that are available to hide small areas of vitiligo on the exposed area. The creams camouflages with the skin such that no one can make out the difference.