epidermolysis bullosa /ep′idərmol″isis/ [Gk, epi + derma + lysis, loosening] , a group of rare hereditary skin diseases in which vesicles and bullae develop, usually at sites of trauma. Severe forms may also involve mucous membranes and may leave scars and contractures on healing. Basal cell and squamous cell carcinomas sometimes develop in the scar tissue.
