Pediatrician Questions nail diseases

What causes a black line in the finger nail?

My teenage daughter has a black line going from the cuticle of her thumbnail to the tip of it. She doesn't know how she got it though, and I asked her if she drew on it or something. What could have caused this?

1 Answer

You would need to get this checked. It could be a melanoma under the nail bed that would need to be removed immediately. Iron deficiency can cause dark line in the nails and sometimes fungus.