Hereditary Angioedema (HAE)

What is hereditary angioedema (HAE)?

Hereditary angioedema (HAE) is a very rare hereditary disease and potentially life-threatening genetic condition. It can cause attacks of swelling that affects deeper layers in your skin, often around your face and lips. Patients often feel pain in the stomach, hands, feet, arms, legs, genitals, throat, or face. Nausea and vomiting is also caused by swelling in the intestinal wall. Depending on the severity of the disease, patients may experience frequent attacks each month, while others are attack-free.  
HAE patients have a defect in the gene that controls a blood protein called C1 Inhibitor (C1-INH). The genetic condition results in production of inadequate or non-functioning C1-Inhibitor protein. Normal C1-Inhibitor helps to regulate the complex biochemical interactions of blood-based systems involved in disease fighting, inflammatory response and coagulation. HAE is classified into 3 types based on what problem the genetic defect causes. 
  • Type I

Low level of C1-INH

C1-INH functions normally

Occurs equally in men and women

The most common: 85% of people with HAE


  • Type II

Normal level of c1-INH

C1-INH does not function normally

Occurs equally in men and women

15% of people with HAE


  • HAE with normal functioning C1-INH (Type III)

Normal level of C1-INH

C1-INH functions normally

More common in women than men

Extremely rare


Risk factors

Have had hereditary angioedema attacks before

Have had other allergic reactions

Have a family history of hereditary angioedema

Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. Because the disease is very rare, it is common for patients to remain undiagnosed, or even misdiagnosed, for many years.
Some patients experience only infrequent and mild attacks and are able to manage their HAE with on-demand or acute treatment. These patients may not require long-term or prophylactic therapy like others. 
  • Affects less than 200,000 people in the US population.
  • Estimated frequency worldwide reported in literature varies from 1 every 10,000 to 1 every 150,000 persons without racial or gender differences
  • Mortality rate from undiagnosed HAE can be as high as 40% and is primarily due to laryngeal attacks
person hereditary angioedema hub

  • "HAE – the Disease." US Hereditary Angioedema Association - HAE. US Hereditary Angioedema Association - HA, n.d. Web. 19 Apr. 2017.
  • "Hives and Angioedema." Mayo Clinic. Mayo Foundation for Medical Education and Research, 09 Nov. 2016. Web. 19 Apr. 2017.
  • "What Is Hereditary Angioedema (HAE)." All About HAE. CSL Behring, n.d. Web. 19 Apr. 2017. 
  • Roche, O., A. Blanch, T. Caballero, N. Sastre, D. Callejo, and M. López-Trascasa. "Hereditary Angioedema Due to C1 Inhibitor Deficiency: Patient Registry and Approach to the Prevalence in Spain." Annals of Allergy, Asthma & Immunology : Official Publication of the American College of Allergy, Asthma, & Immunology. U.S. National Library of Medicine, Apr. 2005. Web. 19 Apr. 2017.
  • "Hereditary Angioedema." National Institutes of Health. U.S. Department of Health and Human Services, 10 Mar. 2017. Web. 19 Apr. 2017.


Chronic inflammation may be caused by a handful of diseases and conditions, including: asthma, rheumatoid arthritis, tuberculosis, and more. Environmental and lifestyle factors, such as excess weight, poor diet, stress, and lack of exercise, can also cause chronic inflammation. Chronic inflammation can cause daily ailments, which may interfere with your daily routine. To combat these complications, check out these 20 tips for chronic inflammation:
chronic inflammation - twenty tips


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