Sonographic appearances of the abdominal manifestations of hereditary angioedema.

Hereditary angioedema (HAE) is the autosomal dominant deficiency of C1-esterase inhibitor. There have hitherto been no reports on the US appearances of HAE. The unique case of a 12-year-old girl with recurrent abdominal pain is reported, in whom HAE was diagnosed by US and family history of paroxysmal dyspnoea, cutaneous swelling and attacks of abdominal pain. Pertinent US features were intestinal oedema and ascites. Sonographic evidence of intestinal swelling was only seen on the initial day of an episode of abdominal pain. Oedema, as demonstrated by MRI the following day, regressed rapidly, whereas ascites persisted for at least 3 days. It is therefore important to perform imaging in the acute phase to demonstrate the massive intestinal oedema, which is characteristic for the disease.