Recurrent intestinal obstruction with acquired angio-oedema, due to C1-esterase inhibitor deficiency

A 52-year male with past history of ulcerative colitis 20 years back (now in remission), developed recurrent small intestinal obstruction at intervals of a few months. CT scan did not detect the cause initially. A repeat CT scan (USA) showed interbowel fluid with transient ascites (serum albumin normal). Angio-oedema was suspected and low C4 with C1-esterase inhibitor (C1-INH) deficiency confirmed the diagnosis. Further investigation showed he was suffering from a chronic low grade small B cell lymphoma. He was treated with Rituximab 375 mg/m2 at intervals of one week for 4 weeks. He is asymptomatic with Transexamic acid (500 mg TDS) for last 1½ years.