Pachyonychia Congenita is a rare, painful genetic autosomal dominant skin disorder that begins at birth or early in life. The disease characterised by dystrophic, thickened skin of the palms and soles, thickened nails, and white patches in mucous membranes. Almost all pachyonychia congenita patients experience constant pain that makes even normal activities such as walking, very difficult and sometimes impossible. Many pachyonychia congenita patient unable to ambulate without a walking aid (crutches, wheelchair, etc.) and cannot work or attend school because of the severity of their condition.

Pachyonychia congenita is caused by mutations in one of five genes that encode keratins, proteins that are the main structural components of skin, nails, and hair. The mutations prevent keratins from forming the strong network of filaments that normally gives skin cells strength and resilience.

There are no FDA approved treatments for pachyonychia congenita.