Gallbladder bleeding associated with microscopic polyangiitis: a case report

A 71-year-old male who had a 6 years history of microscopic polyangiitis (MPA) was admitted to our hospital with a chief complaint of upper abdominal pain and nausea. Abdominal contrast-enhanced CT revealed extravasation of contrast medium in the gallbladder, and the patient was diagnosed with gallbladder bleeding. Although we started conservative treatment, anemia, hypotension and tachycardia had progressed gradually. Therefore, we performed emergent laparoscopic cholecystectomy on the following day. Intraoperative findings showed a remarkably distended gallbladder due to interior clots; however, the cholecystitis itself was not significant. Histopathological findings showed infiltrations of inflammatory cells around the blood vessels and vascular rupture. The postoperative course was uneventful. MPA is a type of ANCA-associated vasculitis. To the best of our knowledge, this is the first report of gallbladder bleeding associated with MPA. Spontaneous hemostasis cannot be expected, instead, surgical treatment must be performed promptly.