Epidermolysis Bullosa Acquisita

Epidermolysis bullosa acquisita (EBA) is an orphan autoimmune blistering disease. Blistering and increased skin fragility can occur at any site of the body with squamous epithelia, i.e. the oral mucosa and/or skin. Through so far unknown mechanisms, tolerance against type VII collagen (Col7) is lost. Subsequently, plasma cells produce autoantibodies directed against Col7. After autoantibody binding, tissue pathology is induced by an inflammatory response that is triggered by the deposited immune complexes. Alternatively, subepidermal blistering can also be induced by so far unknown mechanisms in the absence of inflammation. Accordingly, two different clinical presentations are observed: In inflammatory (or non-mechano-bullous) EBA, tense blisters and/or erosions are found at inflamed skin. Mechano-bullous, also termed classical EBA, presents with skin fragility, blisters, or erosions on non-inflamed skin, leading to subsequent scarring and milia formation. Independent of the clinical presentation, EBA may be complicated by mucous membrane involvement, most often affecting the oral mucosa. Diagnosis is confirmed by the presence of linear immunoglobulin or complement deposits along the dermal-epidermal junction in a perilesional skin or mucosal biopsy and detection of (1) a specific binding pattern of the Ig-deposits, or (2) circulating anti-Col7 antibodies in the serum. Overall, EBA is notoriously difficult to treat. Treatment is based on generalized immunosuppression. Metanalysis of over 1000 EBA cases indicated that either high dose intravenous immunoglobulin or the anti-CD20 antibody rituximab may be best suited to induce remissions. This chapter gives a detailed overview about the disease and its management.