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Inherited epidermolysis bullosa (EB) encompasses a number of disorders characterized by recurrent blister formation as the result of structural fragility within the skin and selected other tissues. All types and subtypes of EB are rare; the overall incidence and prevalence of the disease within the United States are approximately 1/53,000 live births and 1/125 000, respectively and similar estimated have been obtained in some European countries. EB affects individuals from all ethnic origins and there is no gender predilection. Clinical manifestations range widely, from localized blistering of the hands and feet to generalized blistering of the skin and oral cavity, and injury to many internal organs. Four major types of inherited EB have been defined: EB simplex (EBS), junctional EB (JEB), dystrophic EB (DEB), each with numerous subtypes, and Kindler syndrome (see these terms). These forms differ not only phenotypically and genotypically but more importantly by the site of ultrastructural disruption or cleavage. Each EB subtype is known to arise from mutations within the genes encoding for several different proteins, each of which is intimately involved in the maintenance of keratinocyte structural stability or adhesion of the keratinocyte to the underlying dermis. EB is inherited in either an autosomal dominant or autsomal recessive manner, depending on the EB type and subtype. EB is best diagnosed and subclassified by the collective findings obtained via detailed personal and family history, in concert with the results of immunofluorescence antigenic mapping, transmission electron microscopy, and in some cases, by DNA analysis. Extensive differential diagnosis is not usually required in EB. Genetic counseling should be offered to affected families and molecular prenatal diagnosis may be available if the disease-causing mutation in the family has been identified. Optimal patient management requires a multidisciplinary approach, and revolves around the protection of susceptible tissues against trauma, use of sophisticated wound care dressings, aggressive nutritional support, and early medical or surgical interventions to correct whenever possible the extracutaneous complications. Prognosis varies considerably and is based on both EB subtype and the overall health of the patient. |