Cicatricial pemphigoid

Cicatricial pemphigoid is a rare chronic autoimmune subepithelial blistering disease characterized by erosive lesions of the mucous membranes and skin that can result in scarring.:581 It is one of the pemphigoid diseases. Cicatricial pemphigoid is a rare chronic autoimmune subepithelial blistering disease characterized by erosive lesions of the mucous membranes and skin that can result in scarring.:581 It is one of the pemphigoid diseases. The autoimmune reaction most commonly affects the mouth, causing lesions in the gingiva or gums, known as desquamative gingivitis but it can also affect areas of mucous membrane elsewhere in the body, such as the sinuses, genitals, anus, and cornea. When the cornea of the eye is affected, repeated scarring may result in blindness. Brunsting–Perry cicatricial pemphigoid is a rare variant of cicatricial pemphigoid involving the scalp and the neck without mucosal involvement. Nikolsky's sign (gentle lateral pressure) on unaffected mucosa or skin raises a bulla. If no lesions are present on examination it may be useful way of demonstrating reduced epithelial adhesion. In contrast, in Pemphigus, the epithelium tends to disintegrate rather than form a bulla. Nikolsky's sign is present in pemphigus and cicatricial pemphigoid, but not in bullous pemphigoid. In mucous membrane pemphigoid, the autoimmune reaction occurs in the skin, specifically at the level of the basement membrane, which connects the lower skin layer (dermis) to the upper skin layer (epidermis) and keeps it attached to the body. When the condition is active, the basement membrane is dissolved by the antibodies produced, and areas of skin lift away at the base, causing hard blisters which scar if they burst. In other words, this is a desquamating/blistering disease in which the epithelium 'unzips' from the underlying connective tissue, allowing fluid to gather that subsequently manifest as bullae, or blisters.