Pyoderma gangrenosum

DDx

Ulcer secondary to underlying infection (eg, mycobacterial, fungal, tertiary syphilis, amebiasis)
Ulcer secondary to underlying neoplasm
Folliculitis
Arthropod bites (insect bites)
Sweet’s syndrome (acute febrile neutrophilic dermatosis)
Vasculitis (eg, Wegener’s granulomatosis)
Warfarin necrosis

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