Hereditary angioedema is a rare genetic disorder characterized by severe episodic swelling due to accumulation of excessive body fluid (edema).
Commonly affected areas are peripheral extremities (hands and feet), limbs, face, intestinal tract or airway(throat/larynx) which makes it a life-threatening disease.
HAE is caused by mutations in the C1 Esterase inhibitor (C1-IHN) gene. This inhibitor is involved in the regulation of the complement, coagulation and contact (kinin-forming) systems. Patients affected by this C1-INH deficiency may evoke HAE attacks due to stress and trauma. The duration and severity of these attacks can vary widely. On average an attack lasts for 3 to 4 days. There are three different types of HAE, being type I, II and III, depending on the levels of C1 inhibitor protein in the blood. The onset of symptoms begins usually during childhood and worsens during puberty. During an attack, patients typically suffer from excruciating abdominal pain, nausea and vomiting. The management of HAE includes the treatment of acute attacks, short-term prophylaxis in order to prevent attacks and long-term prophylaxis to minimize the severity and frequency of recurrent attacks.
Source: Cowen and Company (2017); rarediseases.org; Genetic Home Reference (U.S. National Library of Medicine)