Answer to Mid-Month Mindbender April 2013

Rajalakshmi T, Inchara YK

Paraneoplastic pemphigus and Pemphigus erythematosus

There are two correct answers to this question.

Paraneoplastic pemphigus is a rare disease affecting the elderly, and is usually characterised by severe mucosal involvement. There is often an associated hematologic malignancy.
There are a number of autoantobodies generated, commonly to desmoplakins and bullous pemphigoid antigen. As a consequence, one encounters the chicken-wire/intercellular pattern on direct immunofluorescence (DIF) testing, in addition to basement membrane staining, with C3 and IgG (see figure below). Confirmation is accomplished by indirect immunofluorescence testing using rat bladder as a substrate or immunoprecipitation.

Pemphigus erythematosus (Senear Usher syndrome) is a variant of pemphigus foliaceus wherein the lesions are distributed on photoexposed areas, particularly the face and V of chest. Antibodies to Desmoglein 1 are found. DIF shows intercellular positivity for IgG along with staining of the basement membrane in a "lupus band" pattern.