What is polyarteritis nodosa?

• Polyarteritis Nodosa (PAN) is a potentially systemic disorder of necrotizing vasculitis of medium-sized arteries Characterized by painful subcutaneous nodules, which can ulcerate • Patients may also present with livedo reticularis • Unknown etiology; may affect any organ (most often skin, peripheral nerves, kidneys, joints, and GI tract) • PAN has been as