Cicatricial pemphigoid (also known as benign mucosal pemphigoid, mucous membrane pemphigoid, or benign mucous membrane pemphigoid) is a rare chronic autoimmune blistering disease characterized by erosive skin lesions of the mucous membranes and skin that results in scarring of at least some sites of involvement. The autoimmune reaction most commonly affects the mouth, causing lesions in the gums, but it can also affect areas of mucous membrane elsewhere in the body, such as the sinuses, genitals and anus. When the cornea of the eye is affected, repeated scarring may result in blindness.