LAUSR

Granulomatosis with polyangiitis (GPA), a vasculitis that most commonly affects small to medium‐size vessels of the respiratory tract and kidneys, may also present with a wide array of skin findings. We present the case of a 12‐year‐old boy with pyoderma gangrenosum–like ulcerations on his lower extremity as the initial manifestation of GPA despite negative cytoplasmic antineutrophilic cytoplasmic antibodies (c‐ANCAs). Although GPA is strongly associated with c‐ANCA, c‐ANCA may be negative on presentation. Thus clinical and pathologic clues must be relied upon when serologic confirmation is negative.