The psoriasis is a chronic benign disease causing increased flaking of the skin. It belongs to the group of papulous and erythemasquamous dermatosis.
A crumbling nail is a symptom of severe psoriasis. It affects a toe- or fingernail which falls apart in crumbs.
Psoriasis often affects the nail besides the skin. The complete destruction of the nail does not happen often. In most cases it causes a partial destruction in form of a translucent discolouration in the nail bed that resembles a drop of oil beneath the nail plate.