What is Acquired Angioedema?
Angioedema is a condition where certain deep layers of skin swell significantly. While it’s commonly known to affect the face and areas inside the mouth, it can also impact the genitals, hands, feet, and the internal lining of the stomach and intestines. Swiftly recognizing angioedema is crucial due to its ability to quickly escalate, becoming a potential threat to life. This danger arises primarily from the swelling within the mouth or throat which could block the airway.
What Causes Acquired Angioedema?
Angioedema, a condition characterized by swelling under the skin, can have several causes. One major cause is the use of angiotensin-converting enzyme inhibitors (ACEIs), a common type of medication taken by millions of people, which is leading to an increase in cases of angioedema. This condition is particularly high among African Americans, who may have increased sensitivity to these medications.
There are several other different triggers for angioedema. For example, it can occur due to allergic reactions to food, drugs, or environmental elements. In addition, nonsteroidal anti-inflammatory drugs (including aspirin) and certain chemicals that prompt the release of histamine (like opiates, specific antibiotics, and muscle relaxants) can cause angioedema.
Another less common cause of angioedema is a deficiency in a specific inhibitor (C1-INH). This can be either inherited (hereditary angioedema) or acquired (acquired angioedema). Acquired angioedema happens due to a lack of C1-INH either through its excess use or inactivation. This condition can be associated with other health disorders such as autoimmune disorders (like lupus) or cancer (like lymphoma).
Angioedema can unexpectedly come and go over two to five days. Aside from the swelling, this condition can also cause severe stomach pain due to swelling of the lining of the stomach. There can be various different conditions associated with recurring acquired angioedema, including different types of disorders related to the lymph system.
Risk Factors and Frequency for Acquired Angioedema
Angioedema is a health issue with different types. However, only 1-2% of cases are classified as either Hereditary Angioedema (HAE) or Acquired Angioedema (AAE). It’s worth noting that HAE is approximately ten times more common than AAE. Pinning down the prevalence of AAE is challenging given its relative rarity and potential to go unrecognized, but it’s estimated to occur between 1 in every 100,000 and 500,000 people.
Specific triggers for these conditions can include trauma, medical procedures, emotional stress, menstruation, oral contraceptives, infections, and certain medications. However, flare-ups can occur without any predictable pattern.
- Most people (over 90%) develop AAE after the age of 40.
- People with AAE experience abdominal pain less than 50% of the time during flare-ups.
- On the other hand, individuals with HAE have abdominal pain more than 80% of the time during flare-ups.
Signs and Symptoms of Acquired Angioedema
If you’re trying to figure out if you’re suffering from hereditary angioedema (HAE) or acquired angioedema (AAE), it’s essential to consider things like medication, food, and environmental factors that might be causing the problem. It’s especially important to consider if drugs like ACE inhibitors or NSAIDs are involved. It’s also useful to know if there have been any similar incidents in the past, either for you or within the family. If there’s no clear cause, then it’s possible that the problem is HAE/AAE.
Differentiating between HAE and AAE can be hard. However, there are a few clues that can help. For instance, AAE tends to occur later in life (after 40) and doesn’t typically appear in families. AAE can also sometimes come with signs that suggest an underlying cancer. Testing the levels of C1 esterase inhibitor and C4 in your blood can help tell if your symptoms are due to HAE or AAE, or another cause altogether.
On a physical examination, angioedema usually shows up as localized, well-defined, non-pitting swelling. This usually affects the lips, tongue, face, and eyelids, though can also show up in places like the larynx, sexual organs, and the ends of arms and legs. Skin rash, know as urticaria, might also be present. Sometimes angioedema can cause recurrent, severe stomach pain similar to what might be seen in a surgical emergency, potentially leading to a bowel resection procedure.
It’s also crucial to think about other possible causes, such as infection, reaction to insect bites, congestive heart failure, or kidney or liver disease. Things that suggest angioedema include a rapid appearance of symptoms, swelling that’s not the same on both sides, and the lack of symptoms that suggest one of the other possibilities.
Testing for Acquired Angioedema
Quick assessment of a person’s airway is vital. Research has shown that factors such as a person’s age and swelling in the mouth or throat can indicate whether an intervention to clear the airway is needed. Other factors such as the involvement of other areas, the reason for the issue, and a person’s sex did not seem to affect this. Another study found that changes in voice, hoarseness, a whistling sound during breathing, or difficulty breathing could be signs of an upcoming blockage in the airway. A fiber-optic scope passed through the nose into the throat can be used to identify any involvement of the voice box.
If the airway needs to be definitively secured, it may be challenging or not possible to view the larynx using a tool because the airway structure might be altered. In such cases, it might be better to use a fiber-optic scope to place the tube while the person is awake. Healthcare professionals may only give the person mild sedation, allowing them to breathe themselves during this procedure since it might be difficult. It is essential to have a plan in place for creating an opening in the neck to the windpipe if securing the airway proves impossible.
Treatment Options for Acquired Angioedema
When someone experiences angioedema, or sudden swelling under the skin, a range of treatments may be used. Initially, the exact cause of the swelling is usually unknown, so the first steps typically involve providing extra oxygen, administering certain medications, and using an injection that can quickly reverse severe allergic reactions. However, in a type of angioedema known as AAE, these standard treatments are often ineffective and not recommended.
To treat AAE, doctors often turn to drugs that can replace or mimic natural proteins in the body that keep swelling under control. For example, drugs that replace a protein called C1-INH (which is usually deficient or dysfunctional in AAE) can often stop an acute attack, though in some cases patients stop responding to these treatments over time. Two other promising drugs for AAE include icatibant and ecallantide, which work by blocking the activity of a substance called bradykinin, which is involved in inflammation and swelling.
If none of these drugs are available, fresh frozen plasma (a type of blood transfusion) may be used. However, this method can sometimes fail to relieve symptoms or even make them worse, and it carries the risk of transmitting viral infections. Another drug, rituximab, also has variable effects in AAE.
If the underlying cause of AAE can be identified and treated, this often leads to improvement in the angioedema.
Regarding emergency care for angioedema, the response to treatment can vary widely, often reflecting the natural progression of the condition rather than the effects of the medications. This means that frequent checks are vital to catch any sudden worsening of symptoms.
Patients with ongoing swelling of the tongue, mouth, or throat, recurrent airway swelling, or ongoing signs of severe allergic reaction (such as low blood pressure, heart problems, or confusion) should be admitted to the hospital for intensive care. If the swelling is limited to the face and lips, or the tongue is swollen but the soft palate (the back part of the roof of the mouth) is still visible, patients may be observed in the emergency department before being sent home, as long as they have a good support system there.
What else can Acquired Angioedema be?
- Blockage of the intestines
- A genetic disorder causing swelling beneath the skin
- Swelling caused by the body’s immune response
