Vitiligo. View of the skin disorder vitiligo around a patient's eye. Vitiligo causes an area of the skin to lose its pigment. It commonly develops on the face, hands, armpits and groin and around pigmented naevi, or moles. Vitiligo is thought to be an autoimmune disorder that causes an absence of melanocytes, the cells responsible for secreting the skin pigment melanin. In mild cases no further treatment may be necessary. Phototherapy is used in more severe cases and, if the areas affected by vitiligo are extensive, chemicals are used to remove pigment from the remaining areas of normal skin.