Hereditary Angioedema

HAE is a rare inherited disease that can cause attacks of swelling, and often pain, in specific parts of the body, including the stomach, hands, feet, arms, legs, genitals, throat and face. Depending on the severity of the disease, some people will have many attacks each month, while others will go months without having an attack.

People with HAE lack or have low levels of a protein called C1 esterase inhibitor (C1-INH); In some cases, C1-INH levels are sufficient, but the protein does not function properly. The defect with C1-INH lies in a person's genetic code, which is why HAE runs in families.

HAE is classified into 3 types depending on the problem caused by the genetic defect. A person may have low levels of C1-INH in the body (HAE type I), poorly functioning C1-INH (HAE type II), or HAE with normally functioning C1-INH (previously known as HAE type III). The latter type is extremely rare and still not well known.

What are the warning signs of a HAE attack?
HAE attacks can occur suddenly and without warning. However, many people notice symptoms in the early stages of an attack, including sudden mood changes, irritability, extreme fatigue, nausea, rash or tingling.