Nodular Subtype of Bullous Pemphigoid.

Background: Itching nodules and papules are common findings. A rare but important differential diagnosis is the nodular subtype of bullous pemphigoid.

Results: The investigators report a female patient presenting with strongly itching papules disseminated over her extremities and trunk. Physical examination revealed multiple erythematous, mostly excoriated papules and nodules on her back, abdomen, and extremities. Histology showed changes compatible with prurigo lesion, and immunofluorescence showed positive results for BP180 and BP230. Considering these clinical, histologic, and immunofluorescence findings, the diagnosis of a nodular subtype of bullous pemphigoid was made. The patient showed healing of lesions under a combination therapy with systemic psoralen and ultraviolet A, topical application of corticosteroids, and systemic therapy with azathioprine and prednisolone.

Conclusions: Pemphigoid nodularis represents the rare prurigo variant of bullous pemphigoid. Typically, lesions show the same immunopathologic and histologic features as in common bullous pemphigoid but mostly without the characteristic clinical finding of bullae.