Pityriasis rubra pilaris is one of many forms of pityriasis, a group of skin diseases characterized by the presence of fine scales on the skin. It is a chronic, inflammatory condition characterized by eruptions or lesions of the skin that tend to be pointy with the appearance of a horn, are a reddish-brown color, and are embedded with hair. The eruptions form yellowish-pink scaling patches. There are two forms of pityriasis rubra pilaris, differentiated by the age of onset. Type I usually occurs in older adulthood; Type II generally presents within the first 5 years of life.
Persistent general exfoliative dermatitis of unknown etiology.
A long-term, slightly inflammatory skin condition where firm bumps with central hard plugs develop at the openings of hair follicles. These bumps often merge to form scaly areas.