Necrotic Leg Nodules as the Initial Cutaneous Manifestation of Multi-System Granulomatosis with Polyangiitis

Abstract

Granulomatosis with polyangiitis (GPA) is an autoimmune vasculitis typically affecting small to medium-sized vessels. Cutaneous findings are varied but classically include those such as palpable purpura and mucocutaneous ulcers. Initial presentation with skin manifestations is associated with worse systemic disease. Here, we describe the challenging diagnosis of a patient with GPA who presented with necrotic leg nodules as the initial clinical cutaneous sign prior to the onset of systemic symptoms. This rare presentation underscores the critical need for dermatologists to consider vasculitic processes when presented with tender leg nodules. We highlight the nuance and important role of dermatological assessments such as biopsies to capture evidence of vasculitis in this context and encourage laboratory testing for vasculitis-associated antibodies, particularly in patients with other vasculitis-associated symptoms.