- An acquired depigmentation of the skin, which correlates with a loss of epidermal melanocytes. There are two major clinical variants, each with subtypes.
- Nonsegmental vitiligo: depigmented macules of varying size
- Acrofacial: on distal extremities and face
- 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
- Rare variants:
- Ponctué: discrete, confetti-like macules
- Inflammatory: peripheral erythematous rim
- Trichrome: Tan zone is present between normal and depigmented skin.
- Quadrichrome: as above but with marginal/perifollicular hyperpigmentation
- Blue: Dermal melanophages give blue hue in areas affected by prior postinflammatory hyperpigmentation.
- Universal: involves >80% of the body surface area (BSA). Most likely to have family history; comorbidities are common and associated with poorest quality-of-life (QOL).
- Segmental vitiligo: Lesions occur within a dermatome (often trigeminal) or may follow Blaschko lines. Lesions usually stop abruptly at the midline; typically occurs earlier than nonsegmental vitiligo, is rapidly progressive, and involves melanocytes of hair follicles.
- Bisegmental: bilaterally distributed
- Plurisegmental: multiple segments
- Unisegmental: single segment
- Focal: few lesions, random distribution; may be able to later classify as one of the forms above after 1 to 2 years
- Mucosal (focal type): only mucosal surfaces
- 50% begin before age 20 years; females in 1st decade; males in 5th decade; onset earlier with positive family history; can appear as early as 6th weeks of life
- Predominance: male = female; however, females are more likely to seek treatment.
- No race or socioeconomic predilection
Etiology and Pathophysiology
Most likely, a spectrum of disorders with a common phenotype and multiple mechanisms contribute to the pathology (convergence theory).
- Autoimmune: humoral autoantibodies and skin-homing T cells
- Neural: local or systemic dysregulation leading to excess neurotransmitters
- Viral: direct melanocyte toxicity, cytomegalovirus (CMV), hepatitis C, and Epstein-Barr virus (EBV) found in lesion biopsies
- Oxidative stress from elevated H2O2 and NO and decreased catalase and erythrocyte glutathione
- Polygenic/multifactorial inheritance
- 20% of patients report affected relative; monozygotic twins have only 23% concordance.
- HLA haplotypes, small nucleotide polymorphisms, and specific genes are all possible contributors.
- Family history of vitiligo/autoimmune disorders
- Personal history of associated conditions
Commonly Associated Conditions
- Most common
- Endocrine: thyroid disease (hypo-/hyperthyroidism), hypoparathyroidism, Addison disease, insulin-dependent diabetes
- Dermatologic: psoriasis, atopic dermatitis, alopecia areata, chronic urticaria, halo nevi, ichthyosis
- Pernicious anemia
- Hypoacusis, rheumatoid arthritis
- Ocular abnormalities in up to 40%
- High antinuclear antibodies in up to 40%
- Elevated thyroperoxidase antibodies in 50%
- Less common
- Systemic lupus erythematosus
- Inflammatory bowel disease
- Melanoma and other skin cancers
- Syndromes: Alezzandrini; mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS); Schmidt; and autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED)
- Age >50 years at onset should prompt investigation for associated conditions.
Associated with Hashimoto thyroiditis in a significant portion of children; screening at onset and possibly annually may be beneficial.
There's more to see -- the rest of this topic is available only to subscribers.