Hereditary angioedema (HAE) is an autosomal dominant disorder characterized by episodic local subcutaneous edema and submucosal edema involving the upper respiratory and gastrointestinal tracts. There are 2 classic types of the disorder. In type I, representing 85% of patients, serum levels of C1NH are less than 35% of normal. In type II, the levels are normal or elevated, but the protein is nonfunctional. The 2 types are clinically indistinguishable.
Confirmation of a clinical diagnosis, Carrier testing in unaffected family members