PNPP is a severe variant of pemphigus that is associated with an underlying neoplasm—most frequently non-Hodgkin’s lymphoma, chronic lymphocytic leukemia, or thymoma Castleman’s disease and Waldenströms macroglobulinemia are also associated with cases of PNPP. Patients with this form of pemphigus develop severe blistering and erosions of the mucous membranes and skin. Treatment of this disease is difficult, and most patients die from the effects of the underlying tumor, respiratory failure due to acantholysis of respiratory epithelium, or
the severe lesions that do not respond to the therapy successful in managing other forms of pemphigus.Histopathology of lesions of PNPP includes inflammation at the dermal-epidermal junction and keratinocyte necrosis in addition to the characteristic acantholysis seen in PV. The results of direct and indirect immunofluorescence also differ from those in PV. DIF shows deposition of IgG and complement along the basement membrane as well as on the keratinocyte surface. Indirect immunofluorescence demonstrates antibodies that not only bind to epithelium but to liver, heart, and bladder tissue as well.