Simultaneous endemic pemphigus foliaceus and psoriasis vulgaris in Peru - immunogenetic or environmental factors?

Endemic pemphigus foliaceus is a rare autoimmune disease typically reported in isolated geographical areas. It is characterized by subcorneal blisters and presence of IgG4 anti-desmoglein 1 autoantibodies. Although a meta-analysis and several case reports suggest an association between pemphigus foliaceus and psoriasis vulgaris, there have been no case reports of endemic pemphigus foliaceus and psoriasis occurring simultaneously in the same patient. In this article, we present three cases depicting concurrent endemic pemphigus foliaceus and psoriasiform eruptions. In the first case, endemic pemphigus foliaceus preceded psoriasis vulgaris, in the second case psoriasis developed first and in the third case we could not determine the chronological order of these diseases. The literature related to this topic is discussed.