Definition
A form of epidermolysis bullosa, a genodermatosis characterized by recurrent blistering, fragility of the skin and mucosal epithelia, and erosions caused by minor mechanical trauma. JEB2B is an autosomal recessive form in which blistering lesions occur between the epidermis and the dermis at the lamina lucida level of the basement membrane zone. It belongs to the severe spectrum of junctional epidermolysis bullosa (previously known as generalized severe or Herlitz type), characterized by onset of blistering over large regions of the body at birth or in early infancy. Blistering also affects the mucous membranes, such as the moist lining of the mouth and digestive tract, which can make it difficult to eat and digest food. The extensive blistering leads to scarring and the formation of red, bumpy patches called granulation tissue. Other complications can include fusion of the fingers and toes, abnormalities of the fingernails and toenails, joint deformities, dental enamel defects, and alopecia. Severe, junctional forms are associated with death in the first 6 to 24 months of life.