What is pemphigus? Pemphigus is a rare disease that causes blistering on many parts of the body, including the skin and the inside of the mouth, nose, throat, eyes, and genitals. In pemphigus, the immune system mistakenly attacks cells in the top layer of the skin.
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.
What is psoriatic arthritis? Psoriatic arthritis is a condition that causes swelling and pain in joints and the places where tendons and ligaments attach to bones. Most people who develop psoriatic arthritis already have psoriasis (a skin disease), but a small number have joint pain before the skin rash.