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Hereditary Angioedema

What is Hereditary Angioedema?

Hereditary Angioedema, also known as C1 Deficiency, is a rare and potentially life threating genetic disorder.  Hereditary angioedema is characterized by recurrent attacks of swelling in the skin, upper airway and gastrointestinal track. People who have hereditary angioedema are born with it, however, they may not begin experiencing symptoms until childhood. Many people do not learn the true cause of the swelling until adulthood.

What are the Symptoms of Hereditary Angioedema?

The primary symptom of Hereditary Angioedema is recurrent swelling that lasts between two and five days. Hereditary Angioedema impacts the following areas: 

  • Skin-  Swelling to the skin, specifically in the hands and feet, can be excruciating. The pain is often a hindrance to the patient's normal daily activities.
  • Abdomen-  Swelling in the intestinal wall leads to recurring pain the abdomen. The swelling and pain are accompanied by nausea, vomiting and diarrhea.
  • Airway or Throat-  Swelling in the throat or in the airway can close the airway, potentially causing death by asphyxiation. Swelling in this area is the most dangerous and life threatening symptom for any Hereditary Angioedema patient. It is imperative to immediately seek medical treatment at the first sign of throat swelling. 

What Triggers Hereditary Angioedema?

The symptoms of Hereditary Angioedema are commonly precipitated by:

  • Mild trauma
  • Oral trauma, such as dental work or oral piercings
  • Viral infections
  • Surgery
  • Pregnancy
  • Certain medication, such as ACE inhibitors

Other, less common, triggers include:

  • Typing
  • Hammering
  • Shoveling
  • Prolonged writing
  • Pushing a lawn mower

A child has a 50% chance of inheriting HAE if one parent has it.

HAE occurs in about 1 in 10,000 people.

Because of rarity, this condition is often misdiagnosed.

What causes Hereditary Angioedema?

There are three types of Hereditary Angioedema.

  • Types I and II are caused by a defect in the gene that controls the C1 Inhibitor.  The C1 inhibitor is a protein in the blood that helps control inflammation. When there is not enough C1, there is an excess of bradykinin in the bloodstream. Too much bradykinin leads to an increased amount of fluid being leaked into the body tissues from the blood vessels, causing inflammation. 
  • Type III is, in some cases, caused by a defect in the gene that aids in the production of coagulation factor XII. This causes an excess in the production of bradykinin. The excess amount of bradykinin causes the blood vessel walls to be more susceptible to leakage, leading to an increased amount of fluid in the body tissues. The increased fluid in the body tissues leads to inflammation. 

How is Hereditary Angioedema treated?

There are two courses of treatments available for Hereditary Angioedema patients: preventative (prophylactic) and on-demand (acute therapy).

  • Preventative (Prophylactic) treatment is used to prevent attacks from taking place. This treatment is often recommended for patients who either experience frequent attacks or who have a lifestyle that is dramatically impacted by their condition.  
  • On-Demand treatment is used to treats the attacks as they occur, reducing both the severity and duration of the attacks.

How can Noble help me manage my Hereditary Angioedema?

At Noble Health Services, we offer a variety of medications to help you treat your symptoms. We help you manage your condition through our Signature Care Program, which includes medication delivery, 24/7/365 on-call support, benefits and co-pay assistance and more. For more information on what medications we offer for hereditary angioedema, please view the enrollment form

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