Felton M.,Felton S.,Kay N; Journal of the American Academy of Dermatology, May 2014

Bilateral superficial granulomatous pyoderma of the auricular and periauricular skin

Journal of the American Academy of Dermatology, May 2014
Author(s): Felton M.,Felton S.,Kay N.
Abstract:  A 36-year-old presented with a 3-month history of a nonhealing 5-mm diameter ulcer in the left conchal bowl. Swabs revealed no bacterial growth, and blood tests, including eosinophil count, were normal and antineutrophil cytoplasmic antibody negative. Histology from excisional biopsy, performed because of suspected malignancy, described extremely acanthotic squamous epithelium with ulcerated areas lined by palisading histiocytes. The dermis had a neutrophilic and in some areas eosinophilic infiltrate, again with palisading histiocytes. The cartilage was degenerate but not inflamed. There was no dysplasia. The key diagnosis proposed was superficial granulomatous pyoderma. The other histologic differentials, infection and systemic vasculitis, were excluded clinically. Unfortunately, he subsequently developed marked ulceration across the ipsilateral periauricular skin and within the contralateral conchal bowl. Some areas have healed with cribriform scarring. Treatment with high-dose oral prednisolone and azathioprine did not provide sustained improvement. Minocycline and dapsone had limited success, whilst more recently he has commenced anti-tumor necrosis factor therapy with infliximab after excluding underlying malignancy.