Les dermatoses linéaires.

Some typical distributions of skin lesions represent a helpful sign for the differential diagnosis in dermatology. Indeed, some dermatoses, affecting the skin, nails or mucosae, display an annular or linear disposition. The linear pattern can be explained by several factors. The dermatosis can follow either a nerve traject, vascular or lymphatic vessels, or embryological lines. Exogenous factors, including traumatisms or automutilations, can also contribute to this particular distribution. In this review, the principal linear dermatoses are discussed together with their pathogenesis.