Tags: Disease.
Koilonychia (from the Greek: koilos- hollow onikh- nail) also known as spoon nails is a nail disease that can be a sign of hypochromic anemia especially iron-deficiency anemia. It refers to abnormally thin nails (usually of the hand) which have lost their convexity becoming flat or even concave in shape. In a sense koilonychia is the opposite of nail clubbing. Koilonychia is associated with Plummer-Vinson syndrome and iron deficiency anemia.