What is angioedema?
An angioedema is an irritation which causes an inflammation on your skin, similar to that caused by hives. However, while hives only affects the superficial layers of your skin, an angioedema affects the subcutaneous layers of the epidermis.
The skin, mucosa and subcutaneous tissues are swollen but there are no welts, which are a sign of hives. While it’s not usually itchy, an angioedema is more severe than hives. Sometimes the two conditions can overlap. The swelling on your skin can last from 24 to 72 hours.
An angioedema is not normally serious and the symptoms don’t usually leave any permanent scars.
An angioedema can become dangerous if it affects the throat by blocking it, causing breathing and swallowing problems which could consequently create a suffocation risk.
What are the symptoms of angioedema?
The most common symptoms are:
- A swelling on specific areas, such as around the eyes, tongue, lips, throat or on the genital area;
- Usually, there is no rash on your skin (compared to what happens with hives);
- A burning sensation, a sense of numbness, itching and pain on the affected area, which also feels hot to the touch;
- Swelling on the abdominal area, if it affects the mucosa in the gastrointestinal tract;
- Difficulty passing urine, if the angioedema affects the bladder or the urethra.
How is angioedema diagnosed?
A doctor specialised in clinical immunology can spot an angioedema by physical examination and after looking at your medical history.
Other tests can help to diagnose an angioedema, such as a blood test and skin prick tests, which can distinguish between allergic angioedema and hereditary angioedema. On the other hand, idiopathic angioedema can be diagnosed by excluding other conditions which may cause similar signs and symptoms.
What causes an angioedema?
There are several underlying causes, depending on the nature of the angioedema:
- Allergic angioedema – can be caused by a food allergy (to shellfish, dairy products, eggs or walnuts) or an allergy to food additives (such as monosodium glutamate), as well as by an allergy to certain medications, to latex, to bees, wasps, snake-bites or jellyfish stings.
- Non-allergic reaction induced by medication.
- Idiopathic angioedema – in the majority of cases when there is no certain cause for the angioedema, it is classified as an ‘idiopathic angioedema’. There are some risk factors which can increase your risk of getting angioedema, such as infections, your alcohol and caffeine intake, eating spicy foods, living in an area with extreme temperatures, wearing tight clothes and stress. Moreover, many cases of idiopathic angioedema are linked to systemic lupus erythematosus (SLE) or other autoimmune diseases.
- Hereditary angioedema – an inherited condition due to a deficiency of C1-inhibitor.
- Acquired angioedema – C1-inhibitor deficiency can become developed during your life, especially if you have lymphoma or other autoimmune conditions.
How can angioedema be prevented?
Idiopathic angioedema can be prevented by giving up certain habits:
- High alcohol and caffeine intake;
- Eating spicy foods;
- Wearing tight clothes;
- Being subject to extreme temperatures, such as a very hot shower or bath or very cool air conditioning.
How is angioedema treated?
If angioedema is causing you breathing problems, it is essential that your airways are opened-up at once (e.g. by intubation).
If it is not causing you any breathing problems, the signs and symptoms of angioedema will disappear on their own either after a few hours or in two to three days time.
Here are some thing you can do to deal with the swelling:
- Applying a cold compress on the affected area;
- Taking a cold (not too cold, though) shower;
- Avoid wearing tight clothes;
- Avoid rubbing the affected area;
- Take antihistamines or corticosteroids;
- In the most severe cases, you may need an adrenaline shot.
Which doctor should I talk to?
You should see a specialist in clinical immunology, who will help you with diagnosing and treating your angioedema.