What are autoimmune diseases? Autoimmune diseases refer to problems with the immune system, which usually fights off viruses, bacteria, and infection. The problem causes your immune cells to attack your body by mistake. These diseases can affect almost any part of the body.
What is pachyonychia congenita? Pachyonychia congenita (PC) is a very rare genetic disorder that affects the skin and nails. Most people have thickened nails and calluses on the bottom of the feet. Painful calluses on the soles can make walking difficult. Because of the pain, some people rely on a cane, crutches, or a wheelchair to help with walking.