A 34-Year-Old With Recurrent Abdominal Pain

A 34-year-old woman had recurrent episodes of crampy, diffuse abdominal pain not relieved by eating or defecation. Laboratory evaluation was unremarkable except for decreased C4 levels; abdominal computed tomography showed jejunal wall edema and ascites; and her father and brother had experienced similar symptoms. What is the diagnosis and what would you do next?