Immunofluorescence in Oral Pathology—Part II: Pathology and Immunofluorescent Patterns in Subepidermal Immunobullous Disorders

The immunobullous disorders are a group of autoimmune diseases in which components of the epidermis and basement membrane zone are targeted, resulting in the formation of cutaneous and mucosal blisters. Based on the level of blistering, the autoimmune blistering diseases may be subdivided into intraepidermal and subepidermal. An exhaustive list of immunobullous disorders is beyond the scope of this review, but those involving oral mucosa are taken into consideration. One major group namely the subepidermal immunobullous diseases which includes bullous pemphigoid (BP), mucosal pemphigoid [cicatricial pemphigoid (CP) or (MMP)], epidermolysis bullosa acquisita (EBA) linear IgA bullous disease (LABD) are discussed in this section. The diagnosis of these diseases requires clinicopathological correlation; immunofluorescence methods provide a useful adjunct to light microscopy. These methods entail the use of fluorescein-linked antibodies to immunoglobulins, complement components, or other proteins either in the skin biopsy or sera. In continuation with part I, the immunofluorescence patterns in the above listed immunobullous disorders are reviewed in detail with a summary of pathogenesis and characteristic histopathological findings.