Hereditary angioedema type 3 (HAE 3) is a form of hereditary angioedema (see this term) characterized by acute edema in subcutaneous tissues, viscera and/or the upper airway.
Prevalence is unknown as there have been very few reported cases (occurring mostly in individuals of French, German and British descent).
Contrary to HAE types 1 and 2, HAE type 3 occurs mainly in women and attacks are often associated with increased estrogen levels (pregnancy, oral contraception, hormonal replacement therapy).
It may be caused by a gain of function mutation in the F12 gene, encoding the coagulation factor 12 (Hageman factor). These mutations cause an increase in factor 12 activity (while C1 inhibitor serum levels and C1 activity remain normal) leading to an increase in bradykinin formation.
There is no licensed treatment for HAE 3 but bradykinin receptor antagonists and C1-INH concentrate have been successful in several cases. Prophylaxis with tranexamic acid is more likely to prove effective than danazol.
Last update: May 2013