DESCRIPTION

• An acquired depigmentation of the epidermis due to a loss of melanocytes. There are two major clinical variants.
• Nonsegmental vitiligo: Represents 80–90% of cases, is often bilateral, symmetrical and enlarges over time (1); subtypes include: the following
  • Acrofacial: on face and distal extremities (“lip-tip” pattern)
  • Generalized: progressive, with flares, commonly associated with autoimmunity; common locations are acral, periorificial, and in sites sensitive to pressure/friction (Koebner phenomenon).
  • Mixed: coexistence of nonsegmental and segmental
  • Mucosal (multifocal): only mucosal surfaces
  • Universal: involves >80% of the body surface area; most likely to have family history; comorbidities are common and associated with poorest quality-of-life (QOL).
• Segmental vitiligo: typically unilateral distribution and earlier onset than nonsegmental (face > trunk > extremities). Lesions may present within a dermatome (i.e., trigeminal), follow Blaschko lines, and involve melanocytes of hair follicles causing leukotrichia. These lesions are less responsive to treatment. Subtypes include:
  • Bisegmental: bilaterally distributed
  • Plurisegmental: multiple segments
  • Unisegmental: single segment
• Undetermined/unclassified:
  • Focal: few lesions, random distribution; may be able to later classify as on one of the forms above after 1 to 2 years
  • Mucosal (focal type): only mucosal surfaces

EPIDEMIOLOGY

• 50% begin before age 20 years; females in 1st decade; males in 5th decade; onset earlier with positive family history
• Predominance: male = female; however, females are more likely to seek treatment.

ETIOLOGY AND PATHOPHYSIOLOGY

Likely a spectrum of disorders with a common phenotype and multiple mechanisms contribute to the pathology.

• Autoimmune: humoral autoantibodies and skin-homing T cells
• Neural: dysregulation of nerve endings leading to decreased melanin production/increased destruction
• Oxidative stress: Exogenous and endogenous stressors increase reactive oxygen species like hydrogen peroxide.

RISK FACTORS

• Family history: vitiligo/autoimmune disorders
• Personal history: associated conditions

COMMONLY ASSOCIATED CONDITIONS

Common comorbidities include (2):

• Autoimmune and connective tissue diseases: systemic sclerosis, alopecia areata, discoid lupus erythematous, Sjögren syndrome, myasthenia gravis, systemic lupus erythematous, rheumatoid arthritis, pernicious anemia
• Endocrine: thyroid disease (hypothyroidism/hyperthyroidism), hypoparathyroidism, Addison disease, insulin-dependent diabetes, metabolic syndrome
• Allergic and dermatologic: psoriasis, atopic dermatitis, lichen planus, chronic urticaria, allergic rhinitis, asthma
• Psychiatric: body dysmorphic disorder, adjustment disorder, impulse control disorder, developmental disorder, suicide and intentional self-inflicted injury, attention deficit hyperactive disorder
• Sensorineural hearing hypoacusis and ophthalmic abnormalities

Pediatric Considerations
Association with Hashimoto thyroiditis; screening at onset and possibly annually may be beneficial.

DIAGNOSIS

HISTORY

• Inquire about recent history of sunburns, pregnancy, skin trauma, or emotional stress.
• Discuss family history of premature graying, vitiligo, and autoimmune disorders.
• Complete a review of systems for related associated conditions.
• Ascertain psychological impact on QOL, Dermatology Life Quality Index.

PHYSICAL EXAM

• Complete a full-body skin exam with Wood lamp (depigmentation appears bright blue-white)
• Lesions are rounded well-demarcated, uniform, white macules and nonscaly patches.

DIFFERENTIAL DIAGNOSIS

• Infectious: tinea versicolor, leprosy, leishmaniasis, onchocerciasis, treponematoses
• Postinflammatory hypopigmentation: psoriasis, atopic dermatitis, pityriasis alba, systemic lupus erythematosus, scleroderma
• Inherited hypomelanosis: piebaldism, tuberous sclerosis, Waardenburg syndrome, hypomelanosis of Ito, Vogt-Koyanagi-Harada disease
• Malformations: nevus anemicus, nevus depigmentosus
• Paraneoplastic: hypopigmented mycosis fungoides, melanoma-associated leukoderma
• Occupational/chemical/drug induced leukoderma
• Melasma: Normal skin may be confused as vitiligo in the setting of surrounding hyperpigmentation.
• Halo nevi
• Lichen sclerosus
• Idiopathic guttate hypomelanosis
• Progressive macular hypomelanosis

DIAGNOSTIC TESTS & INTERPRETATION