Abstract: 【Abstract】 Objective To evaluate the efficacy and safety of 308-nm excimer lamp and 308-nm excimer laser in the treatment of pediatric vitiligo. Methods Clinical data were collected from children with stable vitiligo who received targeted phototherapy at the Department of Dermatology of Xijing Hospital from 2010 to 2015, and retrospectively analyzed. The patients were treated with either 308-nm excimer laser or 308-nm excimer lamp, and all were given topical drugs. The treatment lasted for at least 3 months, and follow-up for at least 6 months. The severity of vitiligo was assessed using the Vitiligo Area and Severity Index （VASI） score. The efficacy was evaluated after 3 months of treatment, and at least a 50% reduction in the VASI score （VASI50） was defined as “effectiveness”. A logistic regression model was constructed using treatment efficacy as the dependent variable to screen factors related to the treatment outcome. The Wilcoxon signed-rank test was used to compare skewed data before and after treatment. Adverse reactions during treatment were recorded to evaluate the safety of targeted phototherapy. Results A total of 194 children with stable vitiligo were included, comprising 103 males （53.1%） and 91 females （46.9%）, with the age being 6 to 14 （10.2 ± 2.3） years. Among them, 138 （71.1%） received 308-nm excimer laser therapy, while 56 （28.9%） received 308-nm excimer lamp therapy. The VASI score （M ［Q1, Q3］） was 0.12 （0.05, 0.40） at the baseline, significantly decreased to 0.06 （0.02, 0.19） after 3 months of treatment （Z = 12.02, P < 0.001）. After 3 months of treatment, 52 patients achieved VASI50, and 30 achieved VASI75, resulting in an overall response rate of 42.3% （82/194）. Specifically, in the 308-nm excimer laser group, 38 patients achieved VASI50 and 26 achieved VASI75, with a response rate of 46.4% （64/138）; in the 308-nm excimer lamp group, 14 patients achieved VASI50 and 4 achieved VASI75, yielding a response rate of 32.1% （18/56）. Univariate logistic regression analysis indicated that lesions located on the head and neck or the trunk were more prone to repigmentation compared with those on the limbs （OR = 3.56, 95% CI: 1.15 - 11.02, P = 0.027; OR = 6.58, 95% CI: 1.81 - 23.96, P = 0.004, respectively）; additionally, facial lesions around the eyes were more prone to repigmentation compared with lesions on other facial areas （OR = 4.58, 95% CI: 1.10 - 19.11, P = 0.037）, and hair involvement in vitiligo lesions on the head and neck made repigmentation less likely to occur compared with lesions without hair involvement （OR = 0.31, 95% CI: 0.13 - 0.75, P = 0.010）. Multivariate logistic regression analysis revealed that the periorbital region was the most favorable site for repigmentation among facial areas （OR = 5.37, 95% CI: 1.18 - 24.34, P = 0.029）, and hair involvement in vitiligo lesions on the head and neck was an independent risk factor for phototherapy-induced repigmentation （OR = 0.28, 95% CI: 0.08 - 0.96, P = 0.042）. Among the 194 patients treated with targeted phototherapy for 3 months, 33 experienced short-term treatment-related adverse reactions, including erythema, blisters, desquamation, itching, and pain; most adverse reactions were mild, and no severe adverse reactions were observed. Conclusion Targeted phototherapy using 308-nm excimer laser or 308-nm excimer lamp was safe and effective for the treatment of pediatric vitiligo.

Key words: Vitiligo, Child, Phototherapy, 308-nm excimer laser, 308-nm excimer lamp, Treatmant outcome, Safety, Influencing factors