Hereditary angioneurotic oedema: an unusual cause of recurring abdominal pain.

Two patients with hereditary angioneurotic oedema, a condition characterized by repeated episodes of abdominal pain and oedema, and by an absence of complement-1 esterase inhibitor activity in the plasma are presented in detail. Both underwent multiple surgical procedures before the diagnosis was established. Abdominal pain is often the presenting complaint, and although a complete history will usually lead to the proper diagnosis, cases in which the family history is not clear can present a diagnostic dilemma. Characteristic radiological demonstration of localized intestinal oedema will only be obtained if studies are performed early during the acute attack.