Polyarteritis Nodosa

Polyarteritis nodosa (PAN) is a systemic necrotizing vasculitis first described in 1866 by Adolph Kussmaul and Rudolph Maier. It typically affects medium-sized arterial vessels but may affect small-sized arterial vessels. Unlike other small-sized arterial vessel vasculitides, polyarteritis nodosa is not typically associated with anti-neutrophil cytoplasmic antibodies (ANCA). It is a systemic disease process; though there is a limited form of the disease called cutaneous polyarteritis nodosa (CPAN). Even with the limited form of the disease, there is significant morbidity secondary to digital ulcerations, ischemia, and painful skin nodules. Though rare, patients with CPAN can progress to systemic polyarteritis nodosa (PAN). PAN chiefly affects the skin but can also involve other organs. The lungs are usually spared.