KRT6A and epidermolytic palmoplantar keratoderma, 1: Finally, a single case with HS and pachyonychia congenita, a genodermatosis associated with severe palmoplantar keratoderma (PPK) and dystrophic nails, has been reported by Pedraz et al. [23] and associated with a pathogenic variant in KRT6A (Keratin 6A) gene.