Pancreatic mass as an initial manifestation of polyarteritis nodosa: A case report and review of the literature

Core Tip

Core tip: A 66-year-old woman presented with a pancreatic mass accompanied by fever, cholestasis and positive myeloperoxidase anti-neutrophil cytoplasmic antibodies. The resected pancreas showed extensive fibrosis associated with necrotizing vasculitis, targeting medium-sized vessels but sparing small-caliber vessels, a finding compatible with polyarteritis nodosa. Unexpectedly, renal biopsy revealed small-caliber vasculitis and glomerulonephritis, supporting microscopic polyangiitis. The initial manifestation of a pancreatic mass associated with vasculitis has only been reported in 7 articles. Although rare, vasculitis should be included in a differential diagnosis for pancreatic masses. Additionally, our findings may reflect a polyangiitis overlap syndrome coexisting between pancreatic polyarteritis nodosa and renal microscopic polyangiitis.