The use of vitamin D analogues may decrease the cumulative UV dose and number of phototherapy treatments required for repigmentation. The fact that vitamin D analogues are degraded by UV light may account for some of the variability seen in the studies, Dr. Grimes said.
▸ Narrow-band UVB. Narrow-band UVB (NB-UVB) phototherapy, which affects both peripheral blood and lesional skin, has moved to the forefront as a treatment for vitiligo. In peripheral blood, narrow-band UVB decreases natural killer-cell activity, cytokine response, and lymphoproliferative responses. In lesional skin, this therapy decreases Langerhans cell activation and increases apoptosis, melanocyte proliferation, and melanogenesis.
NB-UVB has no systemic side effects, requires no posttreatment ocular protection, and has a good safety profile for adults and children. A good response can be achieved even in patients with extensive involvement. “We know that narrow-band [UVB phototherapy] is tremendously well tolerated and easier for the patient,” Dr. Grimes said.
NB-UVB appears to provide a better response than does psoralen with UVA (PUVA). In a recent study, 25 patients with vitiligo were treated with PUVA and 25 with NB-UVB (Arch. Dermatol. 2007;143:578–84). At the end of therapy, 64% of the NB-UVB patients had a greater-than-50% improvement in affected body surface area, compared with 36% of the PUVA group. The color match of the repigmented skin was excellent in all patients in the NB-UVB group, but in only 44% of those in the PUVA group.
On the down side, NB-UVB therapy may require three treatments per week for maximum efficacy. In addition, the long-term carcinogenic effects—as well as the long-term stability of NB-UVB repigmentation—are not known.
“We need more data on the stability of the treatments that we do, as well as [on] the need for maintenance treatment once you achieve repigmentation,” she said.
▸ Polypodium and phototherapy. Polypodium leucotomos (PL), a fern plant grown in Central America that was used in the 1980s as a repigmenting agent, is enjoying a resurgence in interest. The plant has been found to have antitumor and anti-inflammatory effects. It has immunosuppressive properties, reducing CD4 and CD8 levels.
In one study, researchers explored the effects of PUVA plus PL in a pilot randomized, double-blind, placebo-controlled trial with 19 patients who had generalized vitiligo. Skin repigmentation greater than 50% was achieved by a significantly higher percentage of patients in the PUVA-plus-PL arm than in the PUVA-plus-placebo arm (J. Dermatol. Sci. 2006;41:213–6).
“I think that we're going to be seeing more on this combination of Polypodium plus light in the future,” Dr. Grimes said.
▸ Targeted light therapy. Excimer laser-targeted light therapy is another effective option for treating vitiligo. This therapy targets affected skin with a high-intensity light, but avoids exposure to normal skin. Rapid therapeutic responses are seen; cumulative UV exposure is limited.
In addition, targeted light therapy can have a synergistic effect with certain topical agents. Studies suggest that the fastest repigmentation occurs with treatment two to three times per week.
This therapy is a good choice for patients with areas of depigmentation on the genitalia. “Typically in my practice, I tend to avoid treating these areas. But I do have a cohort of gentlemen who are absolutely devastated by genital depigmentation,” Dr. Grimes said. She said she has had good results using targeted light therapy in these patients.
▸ Imatinib mesylate. Imatinib mesylate (Gleevec) is a tyrosine kinase inhibitor that is used for the treatment of chronic myeloid leukemia. “One of the most common side effects is that it induces hypopigmentation and depigmentation,” Dr. Grimes said, so this may be a future depigmenting agent for vitiligo.
▸ Surgical options. Surgical therapy for vitiligo is indicated for stable disease that is focal or segmental and does not respond to medical treatment. It is contraindicated in patients with keloids and hypertrophic scars.
Available procedures include autologous suction blister grafts, autologous melanocyte transplants, autologous punch grafts, sheet grafts, and co-cultures of melanocytes and keratinocytes. “Using these grafting procedures, we actually have the ability to cure some patients who have segmental vitiligo,” Dr. Grimes said.
One new surgical option is a technology called ReCell (Avita Medical Ltd.). This is a single-use, battery-operated, autologous cell harvesting system. The cell suspension is sprayed onto the affected areas of skin.
Dr. Grimes reported that she had no relevant conflicts of interest.
Vitiligo is associated with depression, stigmatization, low self-esteem, and social embarrassment. Courtesy Dr. Steven R. Feldman