Koilonychia

As koilonychia (by alt- gr κοῖλος. Koilos, hollow ' and ὄνυξ onyx, nail ' ) refers to a nail change with trough-shaped depression and increased fragility of the nail plate to congenital or acquired causes ( chronic iron deficiency anemia, eczema, pellagra, sprue, Raynaud's syndrome) can go back. Synonymous with terms such as hollow nails, spoon nails or eggshell nails needed.