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| Fig. 1.5 A, Epidermolysis bullosa of a newborn. B, Ehlers-Danlos syndrome. A large hematoma with poor healing secondary to minor trauma of the lower extremity. |
Collagen. Antibodies against
type VII collagen, which makes up the anchoring filaments within the dermis, are found in the autoimmune diseases
bullous systemic lupus erythematosus (SLE) and
acquired epidermolysis bullosa. Antibodies to laminins 5 and 6, which are also located in the anchoring filaments, are found in bullous SLE patients. The anchoring filaments function to bind the basement membrane to the dermis, and damage to this collagen results in blister formation below the basement membrane. Clinically, blistering damage beneath the basement membrane causes significant scarring in contrast to blisters in the epidermis or above the basement membrane that do not ause scarring.
Congenital epidermolysis bullosa (EB), in which there is a congenital paucity or absence of type VII collagen and anchoring fibers, can result in severe scarring. The most severe form of this disease, recessive dystrophic EB, is associated with “mitten” deformities of the hands and feet, severe scarring of the upper respiratory and gastrointestinal tracts, and early death (Fig. 1-5A).
Congenital abnormalities in the various collagens in the dermis, especially types I and III, are found in several of the Ehlers-Danlos syndromes. The cutaneous manifestations of these syndromes are hyperextensibility of the skin, easy bruising, and poor healing with resultant wide scar formation (Fig. 1-5B).
