Epidermal Basement Membrane Alterations in Epidermolysis Bullosa Acquisita

Immunopathological studies on a patient with clinical evidence of epidermolysis bullosa acquisita (EBA) revealed an increase in type IV collagen in the skin of the chronic scarred lesion, but not in the clinically normal skin. These findings, together with multiplication of the lamina densa of the chronic lesional skin demonstrated by electron microscopy, strongly suggest that repeated injury possibly stimulates epidermal cells to secrete type IV collagen, leading to multiplication of lamina densa of the basement membrane at the dermal-epidermal junction in EBA.