[Painful plantar keratoderma and onychodystrophy in caucasian young woman].

Pachonychia congenita is an uncommon genodermatosis, classified among the disorders of keratinization and caused by mutation of certain keratin genes. The characteristic clinical triad is onychodystrophy, keratoderma, and plantar pain. In addition, the patients may present with epidermal cysts, steatocystomas, leukokeratosis, and deciduous teeth.