Blistering is a rare but important clinical manifestation of amyloidosis that is usually associated with purpura. The occurrence of bullae may be a minor or a major feature of the clinical disorder and usually can be related to trauma.
Primary amyloidosis manifested as epidermolysis bullosa acquisita (EBA) was noted in a 66-year-old woman in whom the absence of visible cutaneous lesions of amyloid belied the presence of an extensive diffuse infiltration of the skin. This infiltration was manifested clinically by the formation of ecchymoses and hemorrhagic bullae after mild trauma, which healed with scarring and milia. An additional interesting finding was the presence of severe alopecia of the scalp, which was due to replacement of the hair follicles by amyloid.
It is suggested that EBA not be considered a primary diagnosis but rather only a manifestation related to some other pathologic disorder. The syndrome of EBA in primary amyloidosis should not be confused with secondary amyloid deposition seen as a complication of infection and debilitation in the congenital forms of epidermolysis bullosa.
Muller SA, Sams WM, Dobson RL. Amyloidosis Masquerading as Epidermolysis Bullosa Acquisita. Arch Dermatol. 1969;99(6):739-747. doi:10.1001/archderm.1969.01610240097018