Vitiligo appears first as one or more white patches over the skin of parts of the body which are relatively more sun-exposed. These include the hands, feet, arms, face and lips. However, patches are also commonly seen over the axillary or inguinal regions, around the navel, the genitalia, and the rectum.
According to the pattern of the patches, vitiligo is classified into three patterns:
Focal
Where patches occur over one or a few areas.
Segmental
Better called unilateral, this form shows patches of depigmentation which occur on one side of the body only. It begins in children or in young adults. It progresses for a limited span of time, usually 1-2 years, after which it remains static.
It is asymmetrical, but the patterns are well-described, repeated from patient to patient, and often resemble each other. In addition they appear to be almost identical to that seen in nevus depigmentosus, suggesting that melanocytes have an embryologically determined pattern of development.
Generalized
There are patches of light skin on both sides of the body, in a symmetrical arrangement. This is the most common form. It may begin at any age, and progresses lifelong in most cases, though in fits and starts. It is notable for its almost perfect symmetry. In a few cases, the depigmentation progresses so rapidly that the entire body, including the hair, loses all pigment. This is called veloce vitiligo or rapid vitiligo.
In addition, vitiligo may also cause hair to lose its color, including the scalp hair and eyelashes, eyebrows and facial hair. There may also be mucosal depigmentation, most commonly noticed by dark-skinned people. Depigmented hair also loses its normal contact hypersensitivity, though the pigmented skin on the same person’s body still reacts normally to the applied substance.
Another significant feature of the newly white skin is its resistance to sunlight-induced skin cancer, such as a melanoma, due to the lack of melanocytes. In addition, this skin does not develop other skin cancers such as squamous cell or basal cell carcinomas which develop from other cells in the skin.
References
Further Reading
Repurposed drug effective at inhibiting a protein kinase linked to cardiac arrhythmias