Difference Between Hereditary vs Acquired Angioedema

hereditary vs acquired angioedema

Hereditary vs Acquired Angioedema: The two forms of Angioedema that are distinguished by recurrent bouts of swelling under the skin's surface or mucosa are Hereditary Angioedema (HAE) and Acquired Angioedema (AAE). AAE is Acquired, frequently as a result of underlying illnesses or drugs that impair C1-INH function, whereas HAE is inherited and results from a deficit or dysfunction of C1 inhibitor (C1-INH). Both disorders are characterised by erratic episodes of swelling, and treatment is based on addressing the underlying cause, which may be Acquired in AAE or genetic in HAE. Medications that target the bradykinin pathway or C1-INH replacement treatment are commonly used in management; the latter is contingent upon the particular ailment and its triggers.

blog banner blog banner

Difference between Hereditary and Acquired Angioedema

A genetic condition known as Hereditary Angioedema (HAE) is typified by repeated episodes of swelling under the skin's surface or mucosa. Usually, it is brought on by a lack of or malfunctioning C1 inhibitor (C1-INH).The table below provides the differences between Hereditary and Acquired Angioedema.


Hereditary Angioedema (HAE)

Acquired Angioedema (AAE)

Underlying Cause

Genetic mutations affecting complement proteins

Production of autoantibodies against complement proteins


Typically starts in childhood or adolescence

Develops later in life, often in adulthood


Stress, infections, hormonal changes, medications

Stress, infections, underlying medical conditions

Frequency of Attacks

Varies widely among individuals

Depends on underlying medical condition


Long-term prophylactic therapy, on-demand therapy

Management of underlying condition, symptomatic treatment


Favourable with proper management

Depends on effective management of underlying condition

Browse The Best Scrubs Collection!

What is Hereditary Angioedema?

A genetic condition known as Hereditary Angioedema (HAE) is typified by repeated episodes of swelling under the skin's surface or mucosa. Usually, it is brought on by a lack of or malfunctioning C1 inhibitor (C1-INH), a protein that controls the complement system and other bodily functions. These periods of swelling can be brought on by stress, trauma, hormonal fluctuations, or specific medications. They can also affect other regions of the body, such as the face, limbs, gastrointestinal tract, or airway. Medication that either raises or replaces C1-INH levels or targets the bradykinin pathway is frequently used to treat HAE to reduce symptoms and stop attacks.

Causes of Hereditary Angioedema

  • Genetic Mutation: The SERPING1 gene, which codes for the production of the C1 inhibitor protein, is the main source of mutations that lead to HAE. These mutations cause a lack or dysfunction of C1-INH, which in turn causes an excessive release of the powerful vasodilator bradykinin and an uncontrollably activated complement system. Angioedema and increased vascular permeability follow from this.
  • Dysregulation of the Complement System: The immune system's complement system is involved in inflammation and pathogen defence. C1-INH often controls the activity of C1r, C1s, and C4 complement proteins. Increased vascular permeability and Angioedema result from the uncontrollably activated complement cascade caused by a deficiency or malfunction of C1-INH.
  • Bradykinin Release: Bradykinin is a peptide that is essential for controlling inflammation and blood pressure. Bradykinin production increases when the complement system is overactive in HAE.
  • Triggers: Although the main cause of HAE is genetics, some people are susceptible to Angioedema attacks, which can be aggravated or precipitated by specific triggers. Stress, trauma, infections, hormonal shifts (such as menstruation or pregnancy), and specific drugs are common factors.

Symptoms of Hereditary Angioedema

  • Swelling: Swelling is the primary sign of Hereditary Angioedema. It usually affects the face, hands, feet, genitals, abdomen, and neck. Swelling may be asymmetrical and accompanied by redness and warmth.
  • Abdominal Pain: Severe abdominal pain, nausea, vomiting, and diarrhoea can all be brought on by gastrointestinal tract swelling. These symptoms may resemble those of other illnesses, such as appendicitis or gastroenteritis.
  • Respiratory Symptoms: Airway swelling can cause difficulty breathing, asthma, coughing, and potentially fatal respiratory distress. In severe circumstances, it might result in asphyxiation. 
  • Skin Symptoms: Itching and urticaria, a raised, red rash, may accompany skin swelling (hives).
  • Fatigue: Angioedema episodes can be physically and emotionally draining, resulting in exhaustion and weakness.

blog banner blog banner

What is Acquired Angioedema?

Acquired Angioedema is an uncommon disorder characterised by periodic periods of swelling (oedema) in the skin's deeper layers, particularly around the face, neck, and gastrointestinal tract. Unlike Hereditary Angioedema, which is characterised by a genetic shortage of a specific protein (C1 esterase inhibitor), Acquired Angioedema results from the development of autoantibodies that attack and deactivate the C1 esterase inhibitor. The C1 esterase inhibitor is a protein that helps regulate immune system functions, particularly those that control oedema. Because of the existence of these autoantibodies, the C1 esterase inhibitor may not operate adequately, resulting in episodes of Angioedema.

Causes of Acquired Angioedema

  • Autoimmune Diseases: Lupus (systemic lupus erythematosus) and rheumatoid arthritis can both cause Acquired Angioedema. In autoimmune disorders, the immune system mistakenly assaults its tissues, causing inflammation and malfunction.
  • Lymphoproliferative Disorders: This group covers illnesses such as lymphoma and leukaemia, which are characterised by aberrant lymphocyte proliferation. Acquired Angioedema can result from immune system abnormalities linked with certain illnesses.
  • Infections: Certain infections, particularly those that influence the immune system or cause aberrant immunological responses, might result in Acquired Angioedema. Examples include hepatitis B and C illnesses.
  • Medication: Certain drugs have been linked to the development of Acquired Angioedema. These could include angiotensin-converting enzyme (ACE) inhibitors, which are frequently used to treat hypertension and heart failure.
  • Idiopathic: In some situations, the aetiology of Acquired Angioedema cannot be recognised, hence it is classed as idiopathic. This indicates that it occurs without any known cause.

Symptoms of Acquired Angioedema

  • Swelling: Swelling is the primary sign of Angioedema and usually affects the mucous membranes and deeper layers of the skin. This swelling can affect many regions of the body, including the face, lips, tongue, throat, and digestive tract.
  • Facial Swelling: Acquired Angioedema frequently results in facial swelling, especially around the lips, eyes, and cheeks. This swelling may occur suddenly and intermittently.
  • Lip and Tongue Swelling: Lip and tongue swelling can cause discomfort, make it difficult to speak, and in extreme situations, make it difficult to breathe or swallow (dysphagia). 
  • Throat Swelling: Swelling in the throat can cause a sensation of tightness or constriction, making it difficult to breathe or swallow. Severe throat swelling is potentially fatal and requires rapid medical intervention.
  • Gastrointestinal Symptoms: Angioedema can cause abdominal pain, cramping, nausea, vomiting, and diarrhoea.

Shop Best Lab Coats From Here!

Similarities between Hereditary and Acquired Angioedema

  • Episodic Swelling: Both disorders are distinguished by recurring bouts of swelling (Angioedema), which can affect any area of the body, including the face, lips, tongue, throat, and gastrointestinal tract. Swelling in both types of Angioedema usually develops in the skin's deeper layers and mucous membranes.
  • Potential Severity: Angioedema episodes, whether Hereditary or Acquired, can range from moderate to severe and last for a variety of times. Severe swelling, especially in the throat, can result in life-threatening consequences such as trouble breathing.
  • Trigger Factors: Stress, trauma, infections, hormonal changes, drugs, or allergen exposure can all cause inherited or Acquired Angioedema.
  • Potential Complications: Both Hereditary and Acquired Angioedema can cause complications, especially if the swelling affects the airway and interferes with breathing. Prompt medical intervention is critical for managing these problems and avoiding serious consequences.

Both Hereditary and Acquired Angioedema (AAE) are characterised by recurring swelling episodes. HAE is Hereditary and begins in childhood, whereas AAE develops later as a result of autoantibodies, which are frequently associated with underlying diseases. Treatments differ, with HAE focused on long-term maintenance and AAE addressing the core problem. The prognosis is dependent on effective management.

Check out More Articles
Difference Between Cartilage and Bone
Difference Between Endocrine and Exocrine Glands
Difference Between Cell Wall and Cell Membrane


What is Hereditary Angioedema (HAE)?

Hereditary Angioedema (HAE) is a genetic disorder that causes repeated swelling (Angioedema) in numerous regions of the body, including the face, throat, and gastrointestinal tract. It is caused by mutations in complement system proteins and typically manifests in childhood or adolescence.

What is Acquired Angioedema (AAE)?

Acquired Angioedema (AAE) is an uncommon illness marked by recurrent episodes of swelling, comparable to HAE. However, AAE occurs later in life as a result of the generation of autoantibodies that target proteins in the complement system, which is usually associated with underlying disorders such as autoimmune illnesses.

What are the common triggers for Angioedema episodes?

Stress, illnesses, hormonal changes, certain medications, and allergen exposure can all provoke HAE or AAE. Identifying and avoiding triggers can aid in managing the disease and reducing the number of episodes.

How is Hereditary Angioedema (HAE) treated?

HAE treatment typically consists of long-term preventive therapy to avoid attacks and on-demand therapy to address acute episodes. Medications including plasma-derived or recombinant C1 inhibitors and bradykinin receptor antagonists may be employed.

How is Acquired Angioedema (AAE) managed?

The treatment of AAE focuses on resolving the underlying disease that causes the Acquired type of Angioedema. Antihistamines, corticosteroids, and other immunomodulatory drugs can also be utilised to treat acute bouts.