Plakophilin 4 and ARVCF expression in a bullous Plakophilin 4 and ARVCF expression in a bullous cutaneous drug reaction

Abstract

The subepidermal vesiculobullous disorders include a wide variety of pathogenically unrelated entities, which share the formation of clefts or bullae. A 59 year old female presented with a sudden eruption of pruritic skin vesicles and blisters on several areas of her body. The patient was taking multiple medications. We decided to test for the expression of p0071 and ARVCF because they are linked with tight, adherens, and occludens cell junctions in the epidermis and the dermis, and study if these molecules participate in the bullae formation. Skin biopsies were taken from lesional skin and were tested by hematoxylin and eosin(H&E) staining, as well as via immunohistochemistry (IHC) and direct immunofluorescence(DIF) using multiple antibodies. ARVCF and p0071 were overexpressed in the epidermis, and in dermal cell junctions around the blisters along with ribosomal protein S6-pS240, Factor XIIIa, CD15, CD45, multiple immunoglobulins, complement, fibrinogen and HLA-DP, DQ, DR antigen. All these molecules were also overexpressed around dermal vessels, eccrine glands and in neurovascular cell junctions below the blister. A normal control did not display the overexpression. Drug reactions may cause blisters; regional cell junctions may be altered, as demonstrated by overexpression of ARVCF and p0071. The overexpression likely contributes to passage of immunologic cells and formation of edema, directly contributing to blister formation.

Keywords

• Subepidermal blisters; Drug reactions; Plakophilin 4;