An epidermolysis bullosa simplex characterized by generalized non-scarring skin blistering that often occurs in clusters, progressive hyperkeratosis of the palms and soles, clumping of keratin filaments in basal epidermal cells and that has_material_basis_in mutation in either the KRT5 or KRT14 genes. This is the most severe of the epidermolysis bullosa simplex types and may result in neonatal or infant lethality in some cases.