Sclerosing and pseudo-sclerosing skin diseases are a therapeutic challenge. Ultraviolet radiation, depending on its wavelength, penetrates into different layers of the skin and acts on cells that promote tissue remodeling and differentiation, such as keratinocytes and fibroblasts. Furthermore, it modulates the inflammatory processes in dendritic cells, endothelial cells, and leukocytes by intervening in the production of cytokines and profibrotic molecules. For these reasons ultraviolet light is a useful option in the treatment of these conditions. Las enfermedades esclerosantes y pseudoesclerosantes de la piel son un grupo de dermatosis que suponen un reto terapéutico para el clínico. La radiación ultravioleta, de acuerdo con su longitud de onda, penetra en las diferentes capas de la piel y actúa sobre aquellas células que favorecen la diferenciación y remodelación tisular como queratinocitos y fibroblastos. Además, modula los procesos inflamatorios en células dendríticas, endoteliales y leucocitos al intervenir en la producción de citoquinas y moléculas profibróticas, volviéndose una alternativa útil en el tratamiento de estas condiciones.

There are a number of conditions that follow the lines of Blaschko. Linear discoid lupus erythematosus is a rare variant of chronic lupus erythematosus with less than 20 cases reported in children. It can be misdiagnosed as lichen striatus or linear morphea. We describe a 15-year-old boy with a confirmed histologic diagnosis of linear chronic discoid lupus erythematosus following the lines of Blaschko, with no signs of systemic involvement.

Pemphigus vegetans is a rare variant of pemphigus vulgaris, characterized by vegetative lesions that develop mainly in flexural areas. Herein, we present a middle-aged woman who presented to the emergency department with a rare cutaneous finding of bilateral axillary pustules that progressed over months to vegetant and malodorous plaques associated with subsequent painful erosions.