Compound Heterozygous Mutations with a Novel Variant in Integrin Beta4 Cause Epidermolysis Bullosa with Pyloric Atresia and Urologic Abnormalities

摘要

Epidermolysis bullosa (EB) with pyloric atresia (PA) is an autosomal recessive form of EB subtype that affects the skin, as well as digestive and frequently urogenital tracts. EB-PA is classified as the simplex form caused by the plectin gene (PLEC) mutations and the junctional form caused by integrin α6β4 genes (ITGA6, ITGB4) mutations.1-5 However, the intracellular domain of integrin β4 interacts with other hemidesmosomal components of basal keratinocytes, including plectin.6 A recent review on the transmission electron microscopy (TEM) findings of EB-PA patients who showed absent expression of integrin β4 reported a consistent level of cleavage planes through concurrent low intra-basal epidermal and lamina lucida,7 suggesting that the loss of integrin β4 can lead to this unique ultrastructural finding.