Pemphigoid nodularis – diagnostic challenges

Introduction
Bullous pemphigoid is an autoimmune bullous disease that occurs most often in old age. The nodular form of pemphigoid may mimic other dermatoses, but also coexist with them, which causes diagnostic and therapeutic difficulties.

Case Report
We present cases of two women (81-year-old and 67-year-old) with a several year history of polymorphic lesions who were initially diagnosed as nodular prurigo. At that time both patients were treated with phototherapy with good tolerance and improvement. During the next courses of UVB-NB irradiation, the condition of their skin deteriorated significantly. Direct immunofluorescence and indirect immunofluorescence studies identified pemphigoid. The initiated pharmacological treatment with methotrexate and systemic glucocorticosteroids resulted in a significant clinical improvement.

Conclusions
Presented cases draw attention to the atypical clinical presentation and the impact of UVB-NB phototherapy on the appearance of the first symptoms of pemphigoid.