Inflammatory and noninflammatory vascular disease causing hemobilia

Typical angiographic finding of polyarteritis nodosa (PAN) shows aneurysms in small- and medium-size arteries, which can assist in diagnosis. Mimics of vasculitis share similar angiographic and clinical manifestations with PAN, making diagnosis confusing. We report 2 patients admitted with hemobilia, one of whom had vasculitis and case of the other mimicked vasculitis.The first patient was an 18-year-old man with epigastric pain. On serial workup, hemobilia with multiple hepatic artery aneurysms was diagnosed and embolized. Later, PAN was confirmed on pathologic examination of gallbladder after cholecystectomy.Second patient was an 18-year-old woman also with epigastric pain. Serial workup revealed multiple microaneurysms of the hepatic artery without bleeding, but 4 days later, fistula between hepatic artery and bile duct was found, and embolization was performed. She was readmitted 1 month later because of hemorrhage of gallbladder, and pathologic examination of gallbladder showed evidence of fibromuscular dysplasia.Clinicians should be aware of mimics of vasculitis when diagnosing gastrointestinal involvement of vasculitis.