Vitiligo: An Update on Pathophysiology and Treatment Options

Reinhart Speeckaert; Nanja van Geel

Disclosures

Am J Clin Dermatol. 2017;18(6):733-744. 

In This Article

Abstract and Introduction

Abstract

The pathophysiology of vitiligo is becoming increasingly clarified. In non-segmental vitiligo, early factors include activation of innate immunity, inflammasome activation, oxidative stress, and loss of melanocyte adhesion. Nonetheless, the main mechanism leading to non-segmental vitiligo involves an immune-mediated destruction of melanocytes. Anti-melanocyte-specific cytotoxic T cells exert a central role in the final effector stage. Genetic research revealed a multi-genetic inheritance displaying an overlap with other autoimmune disorders. However, some melanocyte-specific genes were also affected. Segmental vitiligo carries a different pathogenesis with most evidence indicating a mosaic skin disorder. Current management includes topical corticosteroids and immunomodulators. Narrow-band ultraviolet B can be used in patients not responding to topical treatment or in patients with extensive disease. Pigment cell transplantation offers an alternative for the treatment of segmental vitiligo or stable non-segmental lesions. Recent findings have revealed new targets for treatment that could lead to more efficient therapies. Targeted immunotherapy may halt the active immune pathways, although combination therapy may still be required to induce satisfying repigmentation. A recently established core set of outcome measures, new measurement instruments, and biomarker research pave the way for future standardized clinical trials.

Introduction

Vitiligo is the most frequently occurring depigmentary disorder affecting approximately 0.5–1% of individuals worldwide. It can develop at any age, although half of the patients have vitiligo before the age of 20 years. No difference in prevalence exists according to sex, skin type, or race. Nonetheless, some reports indicate that vitiligo develops in women at an earlier age and marked geographic differences in prevalence rates have been described.[1]

Historically, the cause of vitiligo has been shrouded in mystery. The earliest known reference to vitiligo dates from 2200 BC and vitiligo was also mentioned in the Ebers Papyrus (1550 BC). The development of white spots on the skin has been described in the Old Testament and Buddhist literature.[2] Vitiligo has carried many misconceptions, especially in countries where whitening of the skin is associated with infectious diseases such as leprosy. To date, the resulting social stigmata remain embedded in some cultures, leading to a high psychological burden in patients with vitiligo.[3]

Apart from cultural influences, vitiligo has been shown to exert a detrimental influence on the quality of life. This impact has long been underestimated because of the lack of vitiligo-specific impact scales. Most dermatology qualityof-life measures such as the Dermatology Quality of Life Index focus on subjective symptoms such as pruritus or pain. Moreover, these indices focus on acute disease flares that are not applicable for vitiligo (e.g., Dermatology Quality of Life Index: assessment of patients' complaints in the previous week). Recently, new impact scales have been developed for vitiligo such as the Vitiligo Impact Patient Scale, which may better reflect the burden caused by vitiligo.[4] The psychological impact of vitiligo is clear because of the high rate of depressive symptoms. A recent meta-analysis showed a pooled odds ratio of 5.05 for depression compared with controls. More than a third of patients with vitiligo had experienced some type of depressive symptom without necessary fulfilling all criteria for clinical depression.[5]

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