The patient was a 57-year-old male, who developed bloody stool around May 2006. He was examined by another physician in the department of gastroenterology in our hospital. Gastrointestinal (GI) endoscopy showed a duodenal ulcer, and the biopsy specimen revealed angiitis of the duodenum. He was admitted to our hospital on June 2006. Serum level of creatinine (Cr) was rapidly increased with hematuria and proteinuria. The titer of MPO-ANCA was elevated, and he was diagnosed with microscopic polyangiitis. Steroid pulse therapy was initiated, followed by the administration of prednisolone (PSL : 1 mg/kg/day) and intravenous cyclophosphamide (IVCY). Serum Cr was gradually decreased, but bloody stool was observed from the 10th hospital day. GI endoscopy showed bleeding from the duodenal ulcer. Steroid pulse therapy was performed, and the dose of PSL was increased to 1.5 mg/kg. Endoscopic hemostatic therapy was repeatedly performed without clinical improvement. Pancreatoduodenectomy was performed on the 15th hospital day. However, bleeding from the small intestine was observed repeatedly and the computed tomography of the chest showed cavity-forming nodules, which were diagnosed with angiitis by the biopsy specimen. The additional treatments of steroid pulse therapy, intravenous immunoglobulin therapy, IVCY and Rituximab did not result in favorable response. We report a refractory case of ANCA-related angiitis presented with gastrointestinal ulcer, rapidly progressive nephritis and multiple lung nodules.