Polyarteritis Nodosa Differential Diagnoses

Updated: Oct 07, 2022
  • Author: Dana Jacobs-Kosmin, MD, FACP; Chief Editor: Herbert S Diamond, MD  more...
  • Print

Diagnostic Considerations

The diagnosis of polyarteritis nodosa (PAN) can be difficult because of the spectrum of clinical manifestations and the rarity of the disease. Mimics of vasculitis, including processes that lead to a loss of vascular integrity and blood-vessel occlusion alternate forms of vasculitis, and syndromes associated with vasculitis should be considered. Segmental arterial mediolysis is one example of a noninflammatory vasculopathy that can be misdiagnosed as a vasculitic process. [51] Drugs such as minocycline have been reported to cause cutaneous and systemic PAN-type manifestations. [52] Vitamin K antagonists have also been reported to cause cutaneous necrotic leg ulcers with leukocytoclastic vasculitis and microthrombosis on biopsy. [53]

Microscopic polyangiitis (MPA; formerly called microscopic polyarteritis) and granulomatosis with polyangiitis (GPA; the disease formerly known as Wegener granulomatosis [WG]) are ANCA-associated systemic vasculitides that have some features similar to those of classic PAN, with the additional involvement of renal glomeruli and pulmonary capillaries.

A clear distinction should be made between limited disease versus systemic disease and idiopathic PAN versus hepatitis B–related PAN, because differences exist in the prognosis and treatment.

Finally, some patients with chronic HCV infection can present with vasculitis that is clinically consistent with PAN, not cryoglobulinemic vasculitis.

The entity of HCV-associated PAN may have a more severe presentation compared with HCV-associated cryoglobulinemia. In a cohort of 161 patients with HCV-related vasculitis, 31 patients were diagnosed with PAN. These patients had more frequent fevers, weight loss, GI tract involvement, severe acute sensory-motor multifocal mononeuropathy, kidney and liver microaneurysms, and increased C-reactive protein level than patients with HCV-associated mixed cryoglobulinemia. [19]

Differential Diagnoses