Home phototherapy in vitiligo

Vitiligo is a disorder characterized by the development of depigmented macules and patches. Narrowband ultraviolet B phototherapy is a standard of care treatment and is used both as monotherapy and in combination with other treatment modalities to induce repigmentation. Although phototherapy is safe and effective, its use is limited due to the significant time commitment required and associated costs. Home phototherapy is a safe and effective alternative to make phototherapy more accessible to patients. However, it is often underutilized due to lack of physician experience and comfort as well as misconceptions regarding its safety and efficacy. This article provides a brief overview of the use of phototherapy in vitiligo with a focus on home phototherapy in order to increase awareness and use of this treatment modality.     

Exploring the gaps in the evidence‐based application of narrowband UVB for the treatment of vitiligo

While narrowband ultraviolet light B (NB‐UVB) has become integral to the treatment of diffuse vitiligo, evidence‐based guidelines have been lacking with regard to dosing and administration. This is largely the result of heterogeneous study designs, ambiguous methodologies, disparate dosing strategies, and the use of varied, and somewhat arbitrary, outcome measures. In the absence of prospective trials to address each of these concerns, the available literature regarding the application of NB‐UVB for vitiligo was reviewed and the authors now pose a set of questions to the phototherapy community in an attempt to highlight gaps within our understanding. We aim to stimulate discussion, elicit expert opinion, and identify areas for future research to move toward a unified and safe treatment guideline for patients afflicted by this disease.     

A clinical trial and molecular study of photoadaptation in vitiligo

Background Photoadaptation to ultraviolet (UV) B phototherapy is due to both pigmentary and nonpigmentary influences. Objectives To measure photoadaptation in vitiliginous skin and to compare it with normal pigmented skin. Methods Seventeen patients with Fitzpatrick skin phototypes III–VI with vitiligo received six to nine UVB treatments, two to three times weekly. Minimal erythema dose (MED) testing was done at baseline and after all treatments; the percentage change in MED was analysed as a measure of photoadaptation. The percentage decrease in cyclobutane pyrimidine dimers (CPDs) over 24 h after a single exposure of 1 MED was analysed on vitiliginous and normal skin. Results The mean ± SD percentage change in MED from before to after treatments was: treated vitiliginous skin 28·5 ± 39·9% (P = 0·015), treated normal skin 35·9 ± 49·9% (P = 0·015), untreated vitiliginous skin 11·9 ± 22·6% (P =0·070), untreated normal skin 25·1 ± 41·3% (P = 0·041). Of these patients, two‐thirds had a positive percentage change in MED (photoadaptation). The mean amount of CPDs induced per megabase of DNA immediately after exposure was significantly higher in vitiliginous skin. The mean ± SD percentage decrease in CPDs (rate of repair) in 24 h was 35·7 ± 26·8% in vitiliginous skin (P = 0·027) and 46·2 ± 19·5% in normally pigmented skin (P = 0·001); no difference was noted in the repair in vitiliginous skin compared with normal skin (P = 0·4). Conclusions Photoadaptation in vitiliginous and normal skin was observed in two‐thirds of patients. Vitiliginous skin had significantly more CPDs following UVB exposure; the rate of repair of UVB‐induced DNA damage was equivalent to that in normal skin.     

Effects of psoralen plus ultraviolet A irradiation on cultured epidermal cells in vitro and patients with vitiligo in vivo

BACKGROUND: Both psoralen plus ultraviolet (UV) A (PUVA) and narrowband UVB (NB-UVB) irradiation are effective treatments for vitiligo vulgaris. However, the mechanisms of PUVA and NB-UVB in repigmentation are not thoroughly clarified. Our previous results showed that NB-UVB irradiation directly promotes melanocyte (MC) migration and stimulates MC proliferation via keratinocytes (KCs). OBJECTIVES: In the present study, we used NB-UVB as a reference for comparison to investigate the immediate effects of PUVA on MC proliferation and migration. METHODS: Cultured MCs and KCs were treated with PUVA or irradiated with NB-UVB. The direct impact of PUVA treatment on MCs was assessed in terms of its effect on MC proliferation and migration. The indirect effect of PUVA treatment and NB-UVB irradiation on MC proliferation via KCs was also investigated. The activities of matrix metalloproteinase (MMP)-2 and MMP-9, known for their influence on cell migration, were evaluated in the PUVA-treated MC and KC supernatants. The concentrations of MC mitogens/growth factors in the PUVA-treated KC supernatants were also determined. In addition, the serum levels of MC mitogens/growth factors in healthy controls, in patients with active vitiligo and in patients with repigmenting vitiligo after PUVA treatment were determined to elucidate the mechanisms of how PUVA induces vitiligo repigmentation in vivo. RESULTS: Our results demonstrated that PUVA treatment did not significantly stimulate the release of MC mitogens/growth factors from KCs. The migration of MCs was also not enhanced after PUVA treatment. The expression of MMP-2 activity in supernatants derived from PUVA-treated MCs was significantly increased as compared with the control group. However, neither MMP-2 nor MMP-9 activity in KC supernatants was stimulated by PUVA treatment. In contrast to NB-UVB, immediate effects of PUVA on MC proliferation and migration were not observed in this study. Sera from patients with repigmenting vitiligo after PUVA treatment contained higher levels of basic fibroblast growth factor, stem cell factor and hepatocyte growth factor as compared with healthy controls and patients with active vitiligo. CONCLUSIONS: Our results indicate that in addition to immune suppression, PUVA treatment creates a favourable milieu for promoting the growth of MCs in patients with vitiligo instead of directly stimulating the regrowth of MCs. Based on our results, we propose that in the active stage of vitiligo, PUVA treatment is the therapy of choice to slow down the destruction of MCs and to create a favourable environment for MCs to survive. In the stable stage of vitiligo, NB-UVB irradiation should be used to stimulate the proliferation and migration of MCs directly.     

The challenge of follow-up in narrowband ultraviolet B phototherapy

BACKGROUND: The use of narrowband ultraviolet (UV) B phototherapy to treat psoriasis and other disorders has increased markedly since the TL-01 lamps were introduced in the 1980s. While broadband UVB phototherapy has generally been considered to be a relatively safe treatment, some concern has been raised about the potential increased skin cancer risk with narrowband UVB. OBJECTIVES: The likelihood of a patient who is free of nonmelanoma skin cancer (NMSC) at the start of phototherapy developing a malignancy after a certain follow-up period will be dependent not only on the carcinogenic potential of the treatment but also on the age-conditional probability of natural occurrence. We were interested to explore the potential difficulty of designing studies to separate these two events. Methods Mathematical models were developed that combined age-conditional probabilities of developing NMSC due to natural causes with the risk of inducing these cancers from narrowband UVB phototherapy in order to estimate the excess number of cancers resulting from this therapeutic intervention in a cohort of patients. RESULTS: Within-department studies will be most unlikely to demonstrate that the number of NMSCs observed in follow-up studies is significantly different from that expected in an untreated population, even for a follow-up period of 20 years. CONCLUSIONS: Determination of the carcinogenic potential associated with narrowband UVB will require large multicentre studies typically involving several thousand new patients per year and followed up for 10 years or more.     

A comparison of three times vs. five times weekly narrowband ultraviolet B phototherapy for the treatment of chronic plaque psoriasis

Background: Narrowband ultraviolet B (NB-UVB) phototherapy is an effective treatment for psoriasis.
Objectives: To compare the effects of three and five times weekly NB-UVB phototherapy in the treatment of chronic plaque psoriasis.
Methods: Sixty-five patients with chronic plaque psoriasis were allocated to receive three or five times weekly NB-UVB, starting at low dose.
Results: Among the patients who completed the study, clearance was achieved in 18 out of 23 patients (78%) in the three times weekly group and in 15 out of 22 patients (68%) in the five times weekly group. The difference was not statistically significant ( P =0.44).
No statistically significant differences were found between the two groups in the number of treatments ( P =0.95), cumulative UVB dose ( P =0.51), and rate of side-effects. Length of the treatment period was significantly shorter in the five times weekly group ( P <0.001). At the end of treatment, the mean psoriasis area and severity index score was lower in the three times weekly group ( P =0.02).
Conclusions: We recommend three times weekly NB-UVB for chronic plaque psoriasis; however, the more rapid clearance of psoriasis with five times weekly phototherapy may justify using this method in some patients.     

A randomized, double-blinded, placebo-controlled trial of pseudocatalase cream and narrowband ultraviolet B in the treatment of vitiligo

Background  Pseudocatalase cream in conjunction with narrowband ultraviolet B (NB-UVB) has previously been reported to result in repigmentation of vitiliginous skin.
Objectives  The purpose of this 24-week, double-blind, placebo-controlled, randomized, single-centre trial was to assess the efficacy of pseudocatalase cream and NB-UVB vs. placebo and NB-UVB for the treatment of vitiligo.
Methods  Patients with active vitiligo on their face and/or hands applied either pseudocatalase cream or placebo to their whole body, twice daily for 24 weeks. NB-UVB therapy was administered three times a week for the duration of the trial. Efficacy was assessed primarily by digital image analysis of photographs.
Results  Thirty-two patients were randomized to either the pseudocatalase arm ( n  =   14) or placebo ( n  =   18). Between-group analysis did not show a statistically significant improvement in percentage area affected in the pseudocatalase cream group when compared with placebo. However, a statistically significant improvement was found within each group by week 12, which was maintained throughout the study.
Conclusions  NB-UVB treatment is a moderately effective treatment for vitiligo. Pseudocatalase cream does not appear to add any incremental benefit to NB-UVB alone.     

浓缩生长因子作为生物敷料在稳定期节段型白癜风自体表皮移植术中的应用

 目的 观察浓缩生长因子在稳定期节段型白癜风自体表皮移植中应用的有效性及安全性。方法 纳入65例面部稳定期节段型白癜风患者，随机分为治疗组33例和对照组32例。所有患者均行自体表皮移植，治疗组移植区覆盖自体表皮后，加盖自体浓缩生长因子凝胶膜，然后凡士林纱布覆盖，无菌纱布加压包扎。对照组仅覆盖凡士林纱布。术后两周后，两组患者均行308 nm准分子光照射及外用0.1%他克莫司乳膏。规律随访至术后6个月。 结果 治疗后6个月,治疗组、对照组有效率分别为93.94%和75.00%，差异有统计学意义（X²=12.44,P=0.040) ；色素沉着发生率分别为9.09%和31.25%，差异有统计学意义 （X²=4.99,P=0.026)；光晕现象发生率分别为15.15%和37.50%，差异有统计学意义（X²=4.20,P=0.040)。治疗组感染发生率为3.03%，对照组感染发生率为6.06%，差异无统计学意义 （X²<0.01,P=0.978) 。结论 浓缩生长因子作为生物敷料在节段型白癜风自体表皮移植中应用安全有效，值得临床推广。     

Recent onset vitiligo on acral areas treated with phototherapy: need of early treatment

In vitiligo, the effect of phototherapy depends on lesional location. While face and neck lesions generally show good responses, acral areas are resistant to phototherapy. We describe two cases of recent onset vitiligo on acral areas that showed an excellent response with phototherapy. These results suggest that even acral areas in vitiligo can be markedly improved by phototherapy if it has a recent onset.     

Comparison between 308-nm monochromatic excimer light and narrowband UVB phototherapy (311–313 nm) in the treatment of vitiligo – a multicentre controlled study

BACKGROUND: Vitiligo is an acquired pigmentary disorder characterized by areas of depigmented skin resulting from loss of epidermal melanocytes. Recently, it has been shown that narrowband ultraviolet B (NB-UVB) phototherapy may be more effective than psoralen and ultraviolet A (PUVA) photochemotherapy in treating vitiligo, and that 308-nm monochromatic excimer light (MEL) may present some advantages as compared to NB-UVB for the treatment of vitiligo. AIM The aim of this study was to compare the effectiveness of NB-UVB phototherapy and 308-nm MEL in vitiligo patients. METHODS: The study was done in a randomized, investigator-blinded and half-side comparison design. Twenty-one subjects with symmetrical vitiligo lesions were enrolled in this study. Vitiligo lesions on one body side were treated twice weekly for 6 months with 308-nm MEL, while NB-UVB phototherapy was used to treat lesions on the opposite side. RESULTS: At the end of the study six lesions (37.5%) treated with 308-nm MEL and only one lesion (6%) treated with NB-UVB achieved an excellent repigmentation (score 4) while four lesions (25%) treated with 308-nm MEL and five lesions (31%) treated with NB-UVB showed a good repigmentation (score 3). CONCLUSIONS: It appears that 308-nm MEL is more effective than NB-UVB in treating vitiligo lesions and it induces repigmentation more rapidly.     

窄谱中波紫外线辐射对白癜风黑素细胞生物学特性的影响

目的：探讨窄谱中波紫外线（NB—UVS）辐射对白癜风不同部位培养的黑素细胞生物学特性的影响，以指导设定NB—UVB最佳治疗间隔时间。方法：体外培养白癜风患者外观正常皮肤、皮损边缘处黑素细胞，倒置显微镜观察NB一[NB辐射对细胞形态的影响，MTT法和NaOH法检测NB—UVB辐射剂量（0-100mJ/cm^2，cm^2）和作用时间（辐射后48h、72h、96h）对细胞增殖和黑素合成的作用。结果：①NBUVB（50-mJ/cm^2）辐射黑素细胞后，细胞肿胀，树突缩短增粗，黏附性下降；②NB—UVB辐射后48h，在实验剂量下可提高细胞的黑素合成能力，辐射剂量≥60mJ／cm^2可抑制白癜风外观正常皮肤黑素细胞增殖，而≥40mJ／cm^2即可对皮损边缘处黑素细胞产生抑制作用；NB—UVB辐射后72h、96h，可促进黑素细胞增殖和黑素合成，对白癜风外观正常皮肤黑素细胞作用更明显，辐射后72h黑素细胞增殖率和黑素含量达到最高点。结论：NB—UVB辐射后72h对白癜风黑素细胞功能的影响最大，可用以指导临床设定NB-UVB照射最佳的治疗间隔时间。     

A pilot comparative study of topical latanoprost and tacrolimus in combination with narrow‐band ultraviolet B phototherapy and microneedling for the treatment of nonsegmental vitiligo

Prostaglandins and their analogues are beneficial as topical agents in vitiligo treatment, yet neither of the previous study addressed their comparative efficiency with conventional topical agents used in vitiligo treatment. In this pilot (24 patients) left‐right comparative study we addressed efficiency of prostaglandin F2α analogue latanoprost versus tacrolimus when combined with narrow‐band ultraviolet B and microneedling in repigmentation of nonsegmental vitiligo lesions. Our results confirm potency of prostaglandins, in particular, that of latanoprost, in inducing repigmentation, with the efficiency being at least comparable to that of tacrolimus, while contribution of microneedling remains unclear. In summary, results of our study provide further evidences for justified use of prostaglandins, in particular, latanoprost, in vitiligo treatment. In turn, this warrants future studies on the topic aiming to conclusively introduce prostaglandin‐based formulations as conventional agents for vitiligo management.