Angioedema is a form of edema or swelling underneath the skin or mucosa. It affects the areas of skin where the tissue areas are loose. While all parts of the body can be affected, swelling mostly occurs around the eyes and lips. In severe cases, swelling can also occur in the internal lining of the upper respiratory tracts, intestines and even genitals. It is generally abrupt and short-lived usually caused due to an allergic reaction and not normally serious, but it can be chronic for some people and even life-threatening for an occasional few if breathing is affected due to Angioedema.
While Angioedema and urticaria might appear to be the same, the biggest point of difference between the two is that urticaria affects the top layer of the skin whereas Angioedema affects the subcutaneous tissue (the tissue beneath the skin.
One can even have urticaria and Angioedema at the same time which is why Angioedema is, sometimes, also referred to as “giant hives”. However, one way to identify is by checking its physical appearance. In case of urticaria, red patches and wheals will appear on the skin very reminiscent of a mosquito bite whereas, if you have red or skin-colored swelling below the surface of the skin, it is usually Angioedema.
There are several types of Angioedema and each type is caused by different triggers.
Other triggers like pregnancy, pollen, animal dander, contraceptive pills, trauma or infection can also cause Angioedema in some people.
There are four main types of Angioedema:
Allergic Angioedema –
This is the most common type of Angioedema and is usually triggered by consumption of or exposure to allergens like certain food items like milk, eggs, nuts and shellfish, latex, pollen, pet dander and certain medications. This type of Angioedema is not chronic and can easily be avoided by identifying the allergen causing the reaction.
Drug-induced Angioedema –
Certain medications usually prescribed for hypertension or high blood sugar have ACE (angiotensin-converting enzyme) inhibitors in them. These can cause drug-induced Angioedema. If this is the cause of the swelling, then the doctor will usually prescribe to change the current medications.
Idiopathic Angioedema –
Idiopathic means unknown. So, when an idiopathic Angioedema is diagnosed, that means that despite several tests and checkups, the cause or trigger of Angioedema is still unknown.
Hereditary Angioedema –
When several people in a patient’s family have had Angioedema, that means that the patient’s Angioedema is hereditary. In case of a hereditary Angioedema, there is a gene present in the body that leads to low levels of protein C1-esterase inhibitor in the body. This type of Angioedema has no cure and its symptoms usually come and go over time.
While symptoms of Angioedema may differ based on its type, the following symptoms are common and can normally be identified:
A doctor will be able to form a diagnosis about the type of Angioedema from the type of symptoms, discussion on the cause of swelling, medications the person is currently on and family and medical history.
For e.g., if you have been exposed to a certain allergen before getting Angioedema, then the cause is usually allergic Angioedema. This will sometimes also be accompanied by hives or urticaria. Skin prick testing may be done to identify allergens If there is a history of Angioedema present in the family, then that may be a sign of hereditary Angioedema and the doctor may run the following tests to diagnose it -
Angioedema is best treated by an Allergist.
While acute Angioedema mostly settles by itself in a few days, certain treatments can help settle it faster. These treatments will depend on the type and cause of Angioedema:
In cases where the respiratory tract or the lips are swollen, a person may find difficulty in breathing. The top priority in this case is to ensure a free airway.
In such a scenario, it is important to rush the patient to the hospital for incubation i.e., placement of a tube in the throat to keep the airway open. Sometimes, severe Angioedema may be due to anaphylaxis, a life-threatening, severe allergic reaction which always calls of emergency medical attention.
Depending on its type, Angioedema can be caused through any of the following triggers – insect bites, pollen, pet dander, certain medications like aspirin, penicillin and ACE inhibitors containing medicines, latex and certain types of foods.
If an Angioedema leads to blockage of airways (sometimes happens when the swelling is on the lips or in the respiratory tract), a person may find difficulty in breathing. In such a scenario, medical help is required to place a tube in the throat to keep the airways free.
Certain factors that can increase the risk of Angioedema in a person are -
