Pyoderma gangrenosum vs malignant pyoderma. Lumpers vs splitters.
D003937:Diagnosis, Differential; D006801:Humans; D011711:Pyoderma / Q000209:etiology / Q000276:immunology / Q000473:pathology* / Q000628:therapy; D012883:Skin Ulcer / Q000209:etiology / Q000276:immunology / Q000473:pathology* / Q000628:therapy