An unusual cause of upper gastrointestinal bleeding

Question A 48-year-old man presented to our emergency department with hematemesis and abdominal pain. He was a former heroin addict and had been well until 8 months earlier, when he had epigastric and periumbilical pain, anorexia, 12 kg weight loss and lower back pain. On Examination, his oral temperature was 36.8 ̇C, his pulse was regular with a rate of 92 bpm and blood pressure was 160/95 mmhg. He was appeared pale, the rest of physical examinations were unremarkable, except for mild tenderness in periumbilical area.