Q. A 55-year-old man is brought to the emergency department by his daughter for severe abdominal pain and bleeding per rectum for the past 2 hours. She says her father also has a low-grade fever with body aches and has lost 2 kgs of weight in a month due to poor appetite. He has been taking fever-reducer pills as and when needed. She complains that he hesitates to come to the hospital. His medical history shows that he has chronic Hepatitis B and hypertension. His temperature is 102°F (38.8°C), pulse is 110/min, blood pressure is 140/90 mmHg, and respirations are 16/min. On physical examination, the patient is in distress and has diffuse abdominal tenderness. His lower limbs show livedo reticularis, tender subcutaneous nodules, and multiple healed scars. Laboratory studies are shown below. Mesenteric arteriography shows multiple aneurysms and irregular constrictions in the larger vessels with occlusion of smaller penetrating arteries giving a "string of pearls appearance". What is the best next step in management?