567 - Prognostic factors in pediatric patients with vitiligo
Authors: Morales-Sánchez Martha Alejandra , Villegas-Calzada María Fernanda , Acatitla-Acevedo Graciela Astrid , De Anda-Ortiz Nabil , Peralta-Pedrero Maria Luisa 
Published: February 2024

Abstract

Introduction
Vitiligo is a pigmentary disorder, and its prevalence reaches 2.16% in children.(1) Childhood vitiligo differs from adult vitiligo in clinical characteristics such as higher incidence in females, higher prevalence of segmental presentation and lower association with autoimmune disorders. (2) The course of vitiligo is unpredictable, the disease may regress, stabilize, progress and exacerbate. (3) Few studies of the course of vitiligo have been published.

Objectives
The aim of this study was to identify the clinical characteristics associated with the progression of vitiligo in children and adolescents and also to describe the epidemiological profile in our patients.

Methods
We analyzed the clinical records of a cohort of pediatric patients with vitiligo attended at Centro Dermatológico Dr. Ladislao de la Pascua in Mexico City. Vitiligo diagnosis was defined clinically and to classify patients with NSV we used the revised classification of the Vitiligo Global Issues Consensus Conference. The outcome was the progression of vitiligo, and it was defined as an increase in the extent of the disease at the last visit of follow-up of the patient. We extracted the following data: age at onset, presence of halo nevus, Koebner phenomenon, familial medical history of vitiligo, presence of autoimmune and thyroid disorders. The Koebner phenomenon was considered if lesions were present in areas of friction or if the parents reported their occurrence at sites of previous trauma. Statistical analysis was performed using software SPSS v.25. To calculate the follow-up time we calculate the number of days between the last visit to the first visit of the participant to the center. We define four states according to the clinical course of vitiligo: stable, partial remission, complete remission and progressión. Stable means that the affected body surface area (BSA) did not change over the time, partial remission that the BSA decreased, complete remission means a BSA equal to zero and progression an increase in the involved BSA. We made a survival analysis using Kaplan Meier curves.

Results
Of the 679 participants, 50.2% (341) were males and 49.8% (338) females, giving a male-to-female ratio of 1:1. The average age of onset was 8.6 years (SD 4.4 years). Non-segmental vitiligo (NSV) was more common (55.5%) than segmental vitiligo (44.5). Koebner’s phenomenon was observed in 22.5% of patients and halo nevus was diagnosed in 5% of them. Only 4.1% (28) of the patients had family history of vitiligo; 0.9% had thyroid disorders and 0.3% had been diagnosed with an autoimmune disorder. The mean time of follow up was 11 months. The clinical course of the patients was: stable 44.3%, partial remission 38.7%, complete remission 4.9% and progression in 12.1%. The median time to progression of vitiligo was 71 months equivalent to 5.9 years (95%CI 58.72-83.29 months). The mean time to progression for non-segmental vitiligo was 54.94 months vs. 61.94 patients with segmental vitiligo (p=0.087). Time to progression was different in patients with another skin disease 68.37 months vs. 54.53 months (p=0.015). There were no differences in time to progression for the following variables: treatment, age of onset, gender, family history, Koebner phenomenon, halo nevus and autoimmune disorders.

Conclusions
In our population childhood vitiligo has a slow progression rate and a low prevalence of family history and Koebner's phenomenon compared to other Latin American populations. (4) The ratio of non-segmental to segmental vitiligo and female to male were lower than other countries. (5) Studies with longer follow-up periods are needed to assess progression in vitiligo.