Snapshot A 52-year-old man presents to the emergency department with abdominal pain and rectal bleeding. His symptoms are associated with malaise, fever, and weight loss. He does not have a family history of malignancy and his last colonoscopy was unremarkable. His blood pressure is 155/98 mmHg (his blood pressure is usually 125/74 mmHg). On physical exam, he has abdominal tenderness, livedo reticularis, and cutaneous ulcers. Laboratory testing is notable for a newly elevated creatinine of 2.6 mg/dL, erythrocyte sedimentation rate, and C-reactive protein. He is also seropositive for hepatitis B virus, ANCA-negative, and guaiac positive. Introduction Clinical definition login to view 2 more bullets Epidemiology Demographics login to view 1 more bullet Risk factors login to view 1 more bullet Etiology Idiopathic (most common) Secondary polyarteritis nodosa can result from login to view 3 more bullets Pathogenesis login to view 1 more bullet Presentation Symptoms/physical exam login to view 25 more bullets Imaging Angiography login to view 7 more bullets Studies Studies login to view 7 more bullets Biopsy login to view 3 more bullets Differential Granulomatosis with polyangiitis login to view 4 more bullets Microscopic polyangiitis login to view 4 more bullets Treatment Medical login to view 3 more bullets Complications Thrombosis Hemorrhage Ulcers Prognosis In untreated cases, it is associated with a poor prognosis Hepatitis B-associated disease has a worse prognosis