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An 8-year-old Hispanic boy is brought in to the clinic by his mother, who is concerned about his pigment loss (Figure 167-1). He is starting to develop this vitiligo around the mouth and his mother wants him to be treated. The child was started on a topical steroid and the use of narrow band UVB was discussed if the steroid does not prove helpful. Realistic expectations of the treatments were provided to the mother and her son.
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Vitiligo is an acquired, progressive loss of pigmentation of the epidermis. The Vitiligo European Task Force defines nonsegmental vitiligo as “an acquired chronic pigmentation disorder characterized by white patches, often symmetrical, which usually increase in size with time, corresponding to a substantial loss of functioning epidermal and sometimes hair follicle melanocytes.”1 Segmental vitiligo is defined similarly except for a unilateral distribution that may totally or partially match a dermatome; occasionally more than one segment is involved.1
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Vitiligo occurs in approximately 0.5 to 2 percent of the worldwide population.2,3
It can occur at any age but typically develops between the ages of 10 and 30 years.2
Vitiligo has equal rates in males and females.2
It occurs in all races but is more prominent in those with darker skin.
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Etiology and Pathophysiology
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Autoimmune disease with destruction of melanocytes.
Genetic component in approximately 30 percent of cases. Toll-like receptor genes were found to be associated with vitiligo in a population of Turkish patients.4
Can trigger or worsen with illness, emotional stress, and/or skin trauma (Koebner phenomenon).
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Macular regions of depigmentation with scalloped, well-defined borders (Figures 167-1 to 167-3).
Depigmented areas often coalesce over time to form larger areas (Figure 167-4).
Depigmented areas are more susceptible to sunburn. Tanning of the normal surrounding skin makes the depigmented areas more obvious.
There is no standardized method for assessing vitiligo; strategies include subjective clinical assessment, semiobjective assessment (e.g., Vitiligo Area Scoring Index [VASI] and point-counting methods), macroscopic morphologic assessment (e.g., visual, photographic in natural or UV light, or computerized image analysis), micromorphologic assessment (e.g., confocal laser microscopy), and objective assessment (e.g., software-based image analysis or spectrophotometry).5 Authors of a literature review concluded that the VASI, the rule of 9, and Wood’s lamp were the best techniques for assessing the degree of pigmentary lesions and measuring the extent and progression of vitiligo.5...