Lichen Planus

Lichen planus (LP) is an idiopathic inflammatory disorder affecting the skin, hair, nails, and mucosal membranes that often have a chronic course with relapses and periods of remission. The last two subtypes are very rare. The typical cutaneous lesion of LP in childhood consists of a flat-topped, purple, polygonal, and pruritic papules. Whitish dots or reticulated networks referred to as Wickham striae may be visible over the surface of the papules. The main dermatoscopic feature of LP is represented by Wickham striae, which may appear as pearly-whitish, yellowish, or blue-white structures possibly showing various morphologies, i.e., reticular, linear, “radial streaming,” annular, round, “leaf venation,” and “starry sky” aspects. Additional findings visible in active LP lesions include (1) violet, reddish, pink, brown, or yellow background; (2) vessels with dotted, globular, and/or linear appearance, mainly detectable at the periphery of the lesion and less commonly showing a perifollicular or diffuse pattern; (3) white/yellow dots; and (4) some pigmented structures (dots, globules, and/or reticular or cloudlike areas).