Histologic examination of the skin specimen demonstrated a dense neutrophil-rich interstitial infiltrate of the dermis and subcutaneous tissue, without vasculitis. Significant upper dermal edema and extravasated red blood cells were evident within the epidermis and dermis. The infiltrate did not have atypical features. Special stains and cultures were negative for fungal, mycobacterial, and bacterial organisms. A direct immunofluorescence assay was negative for immunoglobulins and complement deposition. Based on the clinical and immunopathologic features, a diagnosis of PG was made.
A Rapidly Expanding Ulcer—Diagnosis. Arch Dermatol. 2003;139(4):531-536. doi:10.1001/archderm.139.4.531-a