Epidermolysis Bullosa: Group of skin diseases characterized by
recurring painful blisters and open sores, often in response to minor
trauma, as a result of the unusually fragile nature of the skin. There are
three major forms: epidermolysis bullosa simplex, the most common;
junctional epidermolysis bullosa; and dystrophic epidermolysis bullosa. In
epidermolysis bullosa simplex (nonscarring), the blisters occur within the
epidermis. In the Weber-Cockayne variant, blisters are usually confined to the
hands and the feet. The Dowling-Meara variant is characterized by the presence of
blisters on the entire body. About one third of all epidermolysis bullosa simplex
patients experience blisters and sores within the oral cavity that impair feeding
and swallowing. Growth retardation and anemia can be present. Children usually
have normal mental and physical development. In junctional epidermolysis
bullosa (JEB), the blisters occur deeper within the lamina lucida of the basement
membrane zone. Herlitz JEB and non-Herlitz JEB are the two subtypes. Patients
present with widespread painful blisters and skin erosions. The skin is very
fragile and may peel off easily. Dystrophic epidermolysis bullosa (DEB) is
characterized by blisters that develop beneath the basement membrane zone and are
present at, or shortly after, birth. Patients have widespread painful blisters
and sores. The two major subtypes are dominant DEB and recessive DEB. The
Hallopeau-Siemens variant, a recessive form, is the most severe. Blisters appear
on the arms and legs and are widespread, affecting mucous membranes and skin.
Blisters leave scars and small “seed-like” cysts after healing.