Signs and Symptoms of Hereditary Angioedema

The signs and symptoms of hereditary angioedema (HAE) can be difficult to live with. But there are treatments that can help. Knowing what signs to look out for and what to do when symptoms arise can help you or your loved one manage the disease.

What is hereditary angioedema?

Hereditary angioedema (HAE) is a rare genetic condition. This condition causes attacks of inflammation and severe swelling under the skin. The swelling can affect many parts of the body.^1-3

HAE is a hereditary condition. This means it is passed down through families. However, some people are the first in their family to have it. It affects males and females equally. It can impact people of all races.^1-3

Symptoms often start in childhood or the teenage years. The attacks can happen without warning. They can also change over time. An attack can start in 1 place on the body and move to another. For instance, swelling can move from the hands to the face over a period of hours. This makes the condition very unpredictable.^1-3

The condition is rare and affects about 1 in every 50,000 people worldwide. Because HAE is so rare, it can take as long as 10 years to get an accurate diagnosis. Knowing what to look for can help you get the care and treatment you need faster.^1-3

Symptoms of hereditary angioedema

The main symptom of HAE is severe swelling. HAE attacks usually last between 3 to 5 days. They can come and go, making them hard to predict. This swelling most often happens in the following areas of the body:^1-3

• The skin
• The stomach
• The throat

The skin

Swelling often affects the hands, feet, face, and genitals. Skin swelling can make it hard to use your hands or walk. It can make wearing shoes or writing impossible. This swelling does not itch and does not cause hives. This is a key difference from normal allergic reactions.^1-3

The stomach

Swelling in the gut wall causes severe belly pain, nausea, and vomiting. Stomach attacks can feel very painful. They can cause a person to lose fluids quickly. These attacks can look like appendicitis. This often leads to unneeded surgery.^1-3

The throat

Swelling in the airway can make it hard to breathe or swallow. Throat swelling is a medical emergency. It can close the airway and cause death. You must seek emergency care right away if this happens. If this occurs, dial 9-1-1 immediately.^1-3

Why do these symptoms occur?

People with HAE have a problem with a blood protein. This protein is called the C1 esterase inhibitor. This protein regulates the immune system, controls inflammation, and manages fluid balance in the body. When this protein does not work, the body makes too much bradykinin.^1-3

Bradykinin is a chemical that tells blood vessels to release fluid. Extra fluid leaks into nearby tissues. This fluid leak causes the severe swelling attacks.^1-3

HAE swelling is not an allergic reaction and does not involve allergy immune cells and histamine release. Antihistamines, epinephrine pen, and steroids will not treat it.^1-3

There are different types of HAE. Type 1 means the body does not make enough C1 inhibitor. Type 2 means the body makes enough of the protein, but it does not work the way it should. The third type is the rarest and is thought to be caused by other genetic mutations not yet discovered. All 3 types lead to the same swelling symptoms.^1-3

Signs a person might have hereditary angioedema

Some signs can tell you an HAE attack is starting. These early signs (called prodrome symptoms) can warn you. Some people get a non-itchy rash before swelling occurs. This rash looks like red ripples on the skin.^1-3

Other early signs include extreme tiredness, tingling, or anxiety. Some people feel a strange tightness in their skin. These signs can happen a few hours or days before swelling. They vary a lot from person to person.^1-3

There are known triggers that can cause an HAE attack. Common triggers include stress, minor injuries, illness, and surgery. Dental work is a common trigger for throat swelling. Hormonal changes – during menstruation and pregnancy – can also trigger an HAE attack.^1-3

Caregivers should watch for these triggers. Keep a journal of these early signs. A journal helps you find your patterns, which can help prepare you for future attacks.

What parents can do for their children

Because HAE typically begins in childhood, parents need to watch out for repeated swelling or belly pain. Children may complain of stomach aches before any skin swelling appears. Talk to a doctor if you notice these signs.^1-3

Ask the doctor for a specific blood test. The doctor will check C1 esterase inhibitor levels and whether they are functioning properly. These tests can confirm if your child has HAE. Normal allergy tests will not find HAE.¹

If you or a family member has HAE, you may want to look into genetic testing for your child. Testing can find HAE before symptoms even start. This helps you prepare for the future.¹

Create an emergency plan with your doctor. Keep emergency medicines nearby at all times. Teach teachers and school nurses about your child's condition. This keeps your child safe at school.¹

Consider joining a support group for families with HAE. Sharing stories can provide comfort.¹

Caregivers, watch closely

Knowing the signs of HAE can save lives. Severe swelling, belly pain, and early skin rashes are key symptoms. Caregivers should watch children closely for these signs. Work with a doctor to get the right tests and treatment plans so that you can manage HAE.^1-3