[Hereditary angioedema. A rare cause of acute abdominal pain with ascites]

Since the age of 16 years a now 25-year-old woman had been known to have C1-inhibitor (C1-INH) deficiency. She presented herself at the emergency department because of acute severe lower abdominal cramps. A urinary infection had been treated with antibiotics for the previous 4 days. There was marked pain on pressure over the lower abdomen, but there were no signs of peritonitis and bowel sound were normal. There had been no nausea or vomiting and the stools had been normal.

There was a leukocytosis of 10,200/microliter, moderately elevated C-reactive protein (44.8 mg/l), haemoglobin concentration of 17 g/dl and haematocrit of 51%. Radiology revealed oedema of the duodenum and sonography showed free fluid in the abdomen.

After excluding an acute abdomen and in view of the C1-INH deficiency treatment was symptomatic. All symptoms completely disappeared after 2 days.

Exclusively gastrointestinal symptoms and ascites are rare in patients with hereditary angioedema. But knowledge of this manifestation of the disease is important because patients are sometimes operated under the false diagnosis of acute abdomen. In severe cases symptomatic treatment may have to be supplemented by C1-INH administration. Prevention with attenuated androgens should be started or modified, respectively.