Bullous pemphigoid: Diagnosis and management

Bullous pemphigoid, the most common bullous autoimmune disorder of the skin, is primarily a disease of the elderly. It is characterized by autoantibodies that target two structural proteins of keratinocytes, BP180 and BP230. These proteins are localized in the hemidesmosomes and promote adhesion of the epidermis to the dermal stroma. Binding of autoantibodies induces a sequence of inflammatory events that ultimately results in blister formation. Diagnosis of bullous pemphigoid relies on the detection of autoantibodies bound to the skin and/or circulating in the serum by direct and indirect immunofluorescence microscopy, enzyme-linked immunosorbent assay and/or immunoblot techniques. The primary therapeutic aim is the suppression of clinical symptoms of bullous pemphigoid that can be achieved by topical and systemic immuno-suppressive or –modulating approaches. Most often, bullous pemphigoid is treated by low-dose systemic or topical glucocorticoids. Therapy is often combined with steroid-sparing agents, such as dapsone or azathioprine. In mild or localized disease, tetracyclines combined with nicotinamide represent a well-tolerated alternative. In treatment-resistant cases, cyclophosphamide or high-dose intravenous immunoglobulins may be considered. Novel therapeutic strategies, such as B-cell depletion by the monoclonal anti-CD20-antibody rituximab, or immunoadsorption of circulating immunoglobulins, may present effective approaches in refractory disease.