Epidermolysis Bullosa Acquisita (Tardive) and Porphyria Cutanea Tarda

Abstract
Epidermolysis bullosa is generally considered an inherited process beginning early in life, characterized by bulla formation and by erosions of the skin secondary to minor trauma. Occasionally this symptom complex begins in adulthood with no pertinent familial background. A few of these cases of the so-called tardive or acquired form apparently follow severe drug reactions.1,2More commonly, however, the syndrome is found with porphyria cutanea tarda.3-5The differentiation of the idiopathic acquired variety and that associated with porphyria may lead to some diagnostic confusion. We have recently had an opportunity to study concurrently a case of idiopathic epidermolysis bullosa acquisita with no associated familial or toxic background, and a patient with porphyria cutanea tarda. It is the purpose of our report to compare these two patients, not only to establish differentiating features, but if possible to shed some light on the mechanism or mechanisms