HomeHealth articlesinflammationWhat Is Hereditary Angioedema?

Hereditary Angioedema - Causes, Symptoms, Diagnosis, and Management

Verified dataVerified data
0

4 min read

Share

Hereditary angioedema is a condition that causes severe recurrent swelling. This article will share details about its causes, symptoms, and management.

Medically reviewed by

Dr. Shivpal Saini

Published At March 24, 2023
Reviewed AtMarch 24, 2023

What Is Hereditary Angioedema?

Hereditary angioedema is a rare genetic condition that causes recurrent swelling in limbs, face, intestinal tract, and airway. This disorder causes swelling under the skin and at the lining of the guts and lungs. Usually, there are no known triggers that aggravate this condition. However, minor trauma seems to be an aggravating factor for swelling in some cases. It is an autosomal recessive condition caused by either lack of C1 inhibitor protein or a dysfunctional inhibitor protein. Hereditary angioedema is a rare condition affecting 1 in 50,000 people, among which type III is the rarest compared to the other two types. The condition is also known as

  • C1 esterase inhibitor deficiency.

  • C1 inhibitor deficiency.

  • HAE.

  • HANE.

  • Hereditary angioneurotic edema.

What Are the Types of Hereditary Angioedema?

The types of hereditary angioedema are classified as

  • Type I: Type I hereditary angioedema accounts for almost 85 % of the cases. Low C1 inhibitor levels in the blood cause this type of disorder.

  • Type II: Type II hereditary angioedema accounts for almost 15 % of all cases. This type of disorder occurs due to improper protein functioning in the body. However, the C1 inhibitor level is normal or close to normal in the body.

  • Type III: Type III hereditary angioedema is the rarest variant of the disorder. However, it is very similar to the other two types.

What Are the Causes of Hereditary Angioedema?

The following are the etiological factors associated with hereditary angioedema:

  • Type I and Type II: SERPING 1 gene mutation is responsible for the occurrence of type I and type II hereditary angioedema. This gene works as an instructor for making C1 inhibitor protein. This protein is responsible for controlling the inflammatory response of the body. Type I causes a low level of this inhibitor, whereas type II causes an abnormal level. Without the normal level of this inhibitor, the protein fragment called bradykinin is generated. This accelerates the fluid leakage through the blood vessel walls in the tissue and promotes the inflammation reaction in the body.

  • Type III: F12 gene mutation is associated with type III hereditary angioedema. This gene acts as an instructor in making the coagulation factor XII protein. Coagulation factor XII plays an essential role in the blood clotting mechanism and the production of bradykinin. Bradykinin is a peptide that promotes inflammation. With the genetic mutation in F12, the coagulation factor production increases, which leads to increased bradykinin production. This results in leaky blood vessels and gives rise to inflammatory episodes in the body.

What Are the Signs and Symptoms of Pregnancy and Hereditary Angioedema?

The symptoms of hereditary angioedema show its first sign during childhood or puberty and persistently recur throughout life. The followings are the signs and symptoms associated with hereditary angioedema:

  • Nausea.

  • Pain.

  • Nonpruritic wavy rash.

  • Vomiting.

  • Diarrhea.

  • Extreme fatigue.

  • Muscle ache.

  • Tingling.

  • Belly pain.

  • Hoarseness.

  • Mood swing.

What Are the Triggers of Hereditary Angioedema?

The following are the common triggers that cause hereditary angioedema:

  • Stress or anxiety.

  • Minor injury.

  • Surgery.

  • Cold or flu.

  • Continuous physical activities such as typing, hammering, or gardening.

  • Continuous use of medication for heart conditions.

  • Periods.

  • Pregnancy.

  • Use of birth control.

  • Hormone replacement therapy.

How to Diagnose Hereditary Angioedema?

If the episodes of swelling are nonresponsive to the drug treatment, doctors may recommend diagnostic options. If the swelling occurs without any rashes or known triggers to the body, doctors may recommend the following diagnostic options:

History:

  • As the disorder is hereditary, doctors start by asking about family history. Almost 75 % of the cases show a positive family history of this condition.

  • some psychological triggers aggravate the condition, such as stress, and anxiety. Besides these, triggers such as infection or allergies also cause this condition.

Examination:

  • Physical examination of the swellings can also help with the diagnosis.

  • The condition represents airway swelling; the doctors usually look for swelling in the tongue, soft palate, or uvula.

  • Doctors also check for any laryngeal alteration, such as hoarseness or stridor.

  • The condition represents swelling of limbs or face; this can be one of the many factors doctors check for.

Investigation:

  • Measurement of the Components - Levels of C4, C1 inhibitor, and C1q are measured.

Complement Levels in Hereditary Angioedema, Acquired Angioedema, and ACE Inhibitor–Induced Angioedema

complement-levels-in-hereditary-angioedema

What Is the Differential Diagnosis of Hereditary Angioedema?

The following are the differential diagnoses associated with hereditary angioedema:

  • ACE inhibitor-induced angioedema.

  • Acquired angioedema syndrome.

  • Immediate hypersensitivity reactions.

  • Urticaria.

How Is Hereditary Angioedema Managed?

Resuscitation:

  1. In case of an emergency when a person is unable to breathe, immediately seek medical attention.

  2. After careful diagnosis, the doctor may give intravenous C1-INH 20 units/kg over ten minutes.

  3. The doctor might have to go for emergency intubation or a cricothyrotomy.

Initial Management: If an allergy is diagnosed, doctors might refer the case to an immunologist.

Further Management:

  • Facial and Airway Swelling:

  • Upper airway involvement progresses slowly within 20 minutes after the first symptoms appear.

  • In any case of airway involvement, doctors usually recommend C1-INH promptly.

Abdominal Pain and Vomiting:

  • In case of abdominal pain, NSAIDs are given.

  • In case of vomiting, severe pain in the abdomen, or abdominal distention, doctors may go for C1-INH administration.

  • If the symptoms do not improve and last longer than two hours, doctors take a second dose of C1-INH administration along with opiate analgesia and intravenous fluids.

Limb Involvement:

  • Mild swelling usually subsides on its own within a few days.

  • However, for severe cases, doctors may recommend the hospitalization and administration of C1-INH.

Medications:

Long-Term Prophylaxis:

  1. Plasma-derived C1 inhibitor.

  2. Lanadelumab.

  3. Berotralstat.

  4. Attenuated androgens.

  5. Antifibrinolytics.

Short-Term Prophylaxis:

  1. Human nano-filtered purified C1 inhibitor 1000 units intravenous one to two hours before the procedure.

  2. 200 mg of Danazol three times a day.

Follow-up:

Every treatment needs to be followed up, especially if the condition is severe and the treatment was prolonged due to its severity. In this case, the patients should go for regular follow-ups as recommended by doctors.

Conclusion

Hereditary angioedema is a very rare condition. However, the condition might often be neglected due to its common symptoms. The mild symptoms might go away on their own, but in the case of severe signs such as difficulty breathing, the patient should be rushed to the hospital. Moreover, once the treatment is over, the patient should go for a regular follow-up to avoid the recurrence of this condition.

Frequently Asked Questions

1.

Can Hereditary Angioedema Be Cured?

Hereditary angioedema is a genetic disorder that causes swelling in various parts, and it has no cure. But, there are treatments available to manage the symptoms, which include intravenous administration of C1-INH (C1 esterase inhibitor) 20 units/kg is given in case of emergency situation. In case of difficulty in breathing, emergency intubation is carried out. In case of acute attacks, androgens such as Danazol 200 mg are given.

2.

What Is the Survival Rate Associated With Hereditary Angioedema?

Hereditary angioedema is a chronic disorder that is generally not associated with high mortality rates. With proper management, many individuals with HAE can have a normal life expectancy. However, the primary concern in HAE is the potential for swelling episodes that can affect the airway, leading to life-threatening situations that require prompt treatment. The survival rates of individuals with HAE are influenced by the accessibility and availability of medical care.

3.

How Can Hereditary Angioedema Be Visually Identified?

The visual signs of hereditary angioedema (HAE) include swelling in various areas such as the lips, cheeks, tongue, face, extremities, and abdomen. The swelling is typically painless and non-itchy, and it can last for several hours or a few days. Additionally, HAE can cause distortion of the lips and swelling of the cheeks. Another visual sign is periorbital edema, which refers to swelling around the eyes.

4.

What Blood Test Is Typically Performed to Diagnose Angioedema?

Common blood tests used in diagnosing angioedema include measuring the levels and functional activity of C1 inhibitors to identify deficiencies or dysfunction. Additionally, complement C4 levels are often low, and C1q levels may be decreased. Autoimmune markers, such as antinuclear antibodies (ANA), can also be evaluated. A complete blood count (CBC) can help assess signs of inflammation and infection. These blood tests aid in the diagnostic process of angioedema.

5.

What Are the Most Effective Methods to Quickly Alleviate Angioedema?

Some effective methods to quickly alleviate angioedema include the use of medications such as antihistamines and corticosteroids to reduce itching and swelling. Epinephrine can also be used to open the airways in severe cases. Applying cold compresses or ice packs can help reduce swelling. Elevating the affected area promotes fluid drainage. Being aware of previous triggers, such as certain foods, insect bites or stings, medications, or exposure to extreme temperatures, can help avoid angioedema episodes.

6.

At What Age Does Hereditary Angioedema Usually Manifest?

Hereditary angioedema typically begins to manifest during childhood or adolescence, generally between the ages of five and 20. There are three types of hereditary angioedema: Type 1 and Type 2, often present during childhood or adolescence, while Type 3 predominantly affects females and can occur at any age, particularly during adulthood or pregnancy, due to changes in hormones or the use of contraceptives pills.

7.

Are There Natural Remedies or Lifestyle Changes That Can Help Reduce Angioedema Symptoms?

Some natural remedies and lifestyle changes can help reduce angioedema symptoms. These include avoiding triggers such as certain foods, medications, stress, environmental factors, and insect bites. Making dietary changes, such as avoiding processed foods, histamine-rich foods like aged cheese, and artificial additives, can also be beneficial. Involving stress-reducing activities like meditation and yoga may help prevent the development of angioedema symptoms.

8.

Who Is at a Higher Risk of Developing Angioedema?

Certain risk factors for angioedema include a family history of the condition, as it can be inherited in an autosomal dominant pattern with a 50 percent chance of developing the disorder. A history of allergies, such as asthma or rhinitis, can also increase the risk. Additionally, the use of certain medications, such as angiotensin-converting enzyme (ACE) inhibitors, can contribute to the development of angioedema. Individuals who have previously experienced angioedema are at a higher risk of recurrence. Hormonal changes, including those during pregnancy or due to hormonal contraceptives, can also increase the risk of angioedema.

9.

How Serious Is Hereditary Angioedema?

The severity of hereditary angioedema can vary among individuals. The severity depends on the frequency, location, and severity of swelling. When swelling affects the airways, it can cause difficulty breathing, which can be potentially life-threatening. Therefore, in case of an emergency, prompt and quick management is necessary to prevent complications.

10.

Is Hereditary Angioedema Considered an Allergic Condition?

Hereditary angioedema (HAE) is a genetic disorder and not an allergic condition. It occurs due to a deficiency in the C1 inhibitor protein, which regulates the complement system that is the body’s immune system.  HAE is inherited in an autosomal dominant manner, in which there is a 50 percent chance of inheriting the disorder if one parent has it.

11.

What Are the Potential Dangers Associated With Angioedema?

Potential dangers associated with angioedema include airway obstruction, leading to difficulty breathing. Apart from these, swelling involving the throat and tongue can impair speech and swallowing, and periorbital edema can affect vision. Recurrent episodes of angioedema may cause fear and anxiety, impacting an individual's quality of life.

12.

Are There Specific Foods That Individuals With Hereditary Angioedema Should Avoid?

Certain food triggers that can be avoided in individuals with hereditary angioedema (HAE) include histamine-rich foods such as smoked meats, aged cheese, fermented foods, and alcoholic beverages. Additionally, food additives like artificial colors, preservatives such as sulfites, and flavor enhancers such as monosodium glutamate - MSG can also act as triggers. Furthermore, common food allergens like eggs, fish, peanuts, wheat, and tree nuts can also potentially trigger the condition.

13.

Which Type of Medical Specialist Typically Manages Hereditary Angioedema?

Hereditary angioedema is treated by specialists called allergists and immunologists. Immunologists assist in diagnosing and treating immune system-related disorders, including autoimmune disorders and immunodeficiencies. Allergists are also capable of diagnosing immune responses to various allergens, such as asthma, rhinitis, insect allergies, and food allergies.

14.

Is Angioedema Classified as an Immune Disorder?

Angioedema is classified into three types: hereditary angioedema (HAE), acquired angioedema (AAE), and idiopathic angioedema. HAE is a genetic disorder that occurs due to dysfunction of the C1 inhibitor protein. On the other hand, acquired angioedema is considered an immune-mediated disorder, while the cause of idiopathic angioedema is unknown.
Dr. Shivpal Saini
Dr. Shivpal Saini

General Surgery

Tags:

inflammation
Community Banner Mobile
By subscribing, I agree to iCliniq's Terms & Privacy Policy.

Source Article ArrowMost popular articles

Do you have a question on

inflammation

Ask a doctor online

*guaranteed answer within 4 hours

Disclaimer: No content published on this website is intended to be a substitute for professional medical diagnosis, advice or treatment by a trained physician. Seek advice from your physician or other qualified healthcare providers with questions you may have regarding your symptoms and medical condition for a complete medical diagnosis. Do not delay or disregard seeking professional medical advice because of something you have read on this website. Read our Editorial Process to know how we create content for health articles and queries.

This website uses cookies to ensure you get the best experience on our website. iCliniq privacy policy