What is the most suitable treatment for segmental vitiligo?

Segmental vitiligo is a specific type of vitiligo characterised by depigmented patches distributed unilaterally. Less common than the non-segmental form, it accounts for approximately 10% of vitiligo cases. Segmental vitiligo is distinguished by the early onset of its lesions, typically appearing in childhood, and its rapid spread, within six to twenty-four months. Subsequently, the macules stabilise and cease to evolve, or do so very little. The pathogenesis of vitiligo segmental is currently unknown, although an increase in pro-inflammatory cytokine levels and the destruction of secondary melanocytes in response to oxidative stress are suspected. Unlike the more traditional non-segmental vitiligo, segmental vitiligo appears to be less associated with an autoimmune aetiology. Several treatments are available to target it and thus improve the quality of life of affected patients.

Corticosteroids and calcineurin inhibitors to improve segmental vitiligo?

Topical corticosteroids and calcineurin inhibitors play a significant role in the therapeutic arsenal for segmental vitiligo. Indeed, these medications stimulate the migration and proliferation of melanocytes by suppressing pro-inflammatory cytokines, such as IL-1, IL-4, TNF-α, and IFN-γ, and inflammatory CD8+ cytotoxic T cells. Additionally, calcineurin inhibitors induce melanogenesis by releasing stem cell factor and endothelin-1 from keratinocytes and upregulating the level of tyrosinase. Treatments involving corticosteroids or calcineurin inhibitors typically last between six and twelve months, with repigmentation often beginning after the first month. However, although these medications are generally well-tolerated, the results of the few studies conducted on their effects on segmental vitiligo are mixed. Indeed, in most cases, relatively low repigmentation rates have been achieved, close to 20%.

Topical treatments generally have limited effectiveness in cases of segmental vitiligo.

Is phototherapy beneficial for segmental vitiligo?

Another possibility for improving the appearance of segmental vitiligo macules is phototherapy. Depending on the device used, this promotes the migration of melanocytes from the surrounding skin to the depigmented lesion. Furthermore, phototherapy inhibits inflammatory cytotoxic T cells. A recent retrospective study involving 26 children with segmental vitiligo demonstrated its effectiveness. After receiving at least ten doses of excimer laser, 65.4% of them observed a repigmentation greater than 75%, while 7.7% showed partial repigmentation. It should be noted that better results were obtained in patients whose segmental vitiligo had developed in the six months preceding the intervention. Indeed, all individuals with recent segmental vitiligo saw a repigmentation greater than 75%, which was not the case for others.

However, another study conducted with 15 individuals suffering from segmental vitiligo did not reach the same conclusions. After regular sessions of UVB phototherapy over six months, the repigmentation rates of the patients were quite low and remained below 25%. It was not specified, however, how long these individuals had been suffering from segmental vitiligo. Indeed, the previously mentioned study showed that the results varied depending on the duration of the segmental vitiligo. Thus, the low repigmentation observed could be explained, at least in part, by a segmental vitiligo that has been established for an extended period.

Phototherapy and laser treatments could be effective in combating segmental vitiligo, if it has recently developed.

Surgical treatments, alternatives against segmental vitiligo?

When segmental vitiligo has been stable and established for several months, or even several years, it is generally necessary to resort to surgical treatment to make it disappear. This can involve different types of skin grafts (SBEG, STSG...) or transplants of melanocytes and keratinocytes (MKTP). Most often, a skin graft is performed because MKTP is a complex process requiring staff who have received extensive training and specific laboratory equipment, particularly for cultivating melanocytes and keratinocytes.

Several studies have reported the effectiveness of autologous skin grafting for repigmenting areas of skin prone to segmental vitiligo. This method involves taking healthy skin cells from a pigmented area, then grafting them into the depigmented area. Notably, a study was conducted with 15 patients with dark skin who had been suffering from the disease for at least three years. After the autologous graft, repigmentation of more than 90% was observed in 12 individuals. Generally, all patients observed a repigmentation of more than 60%. These excellent results were subsequently confirmed in other clinical trials, all mentioning repigmentation rates of over 55%.

Surgical therapies have long been the cornerstone of treatment for established segmental vitiligo.