THE COMPARISON
A Vitiligo in a young Hispanic female, which spared the area under a ring. The patient has spotty return of pigment on the hand after narrowband ultraviolet B (UVB) treatment.
B Vitiligo on the hand in a young Hispanic male.
Vitiligo is a chronic autoimmune disorder characterized by areas of depigmented white patches on the skin due to the loss of melanocytes in the epidermis. Various theories on the pathogenesis of vitiligo exist; however, autoimmune destruction of melanocytes remains the leading hypothesis, followed by intrinsic defects in melanocytes.1
Vitiligo is associated with various autoimmune diseases but is most frequently reported in conjunction with thyroid disorders.2
Epidemiology
Vitiligo affects approximately 1% of the US population and up to 8% worldwide.2 There is no difference in prevalence between races or genders. Females typically acquire the disease earlier than males. Onset may occur at any age, although about half of patients will have vitiligo by 20 years of age.1
Key clinical features in people with darker skin tones
Bright white patches are characteristic of vitiligo. The patches typically are asymptomatic and often affect the hands (FIGURES A and B), perioral skin, feet, and scalp, as well as areas more vulnerable to friction and trauma, such as the elbows and knees.2 Trichrome lesions—consisting of varying zones of white (depigmented), lighter brown (hypopigmented), and normal skin—are most commonly seen in individuals with darker skin. Trichrome vitiligo is considered an actively progressing variant of vitiligo.2
An important distinction when making the diagnosis is evaluating for segmental vs nonsegmental vitiligo. Although nonsegmental vitiligo—the more common subtype—is characterized by symmetric distribution and a less predictable course, segmental vitiligo manifests in a localized and unilateral distribution, often avoiding extension past the midline. Segmental vitiligo typically manifests at a younger age and follows a more rapidly stabilizing course.3
Worth noting
Given that stark contrasts between pigmented and depigmented lesions are more prominent in darker skin tones, vitiligo can be more socially stigmatizing and psychologically devastating in these patients.4,5
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