Angioedema

It is a cutaneous-vascular syndrome in which a series of characteristic edematous lesions appear on the skin and mucosa, which are similar in urticaria and angioedema (or angioneurotic edema), except for the location of the pathological lesion. , this being more profound in the case of angioedema. Therefore both terms, urticaria and angioedema, are in a certain way synonymous, and may or may not be associated with each case.

Based on the evolution, they can be classified into acute or chronic forms depending on whether the duration of the lesions is greater or less than 6 weeks.

Causes of angioedema

Angioedema appears as a reaction to different stimuli; According to the agent that triggers it, we can classify it into:

Immune angioedema

It occurs in response to different agents that provoke an immune reaction on the part of the host. They can be food antigens such as milk, eggs, nuts …, drugs, infestations by parasites, or blood or immunoglobulin transfusions.

Physical angioedema

Associated or not with urticaria, it appears as a reaction to a physical stimulus such as cold, sunlight, physical exercise (cholinergic urticaria) or by pressure or friction in a certain area of ​​the body.

Hereditary angioedema

It is a hereditary alteration of the complement system, which is involved in the initiation of some immune reactions, and which in these cases is more activated by a deficiency of a factor that usually inhibits it.

Idiopathic angioedema

It is an angioedema of unknown origin, and it is diagnosed after ruling out other causes.

What symptoms appear?

The characteristic lesions in the case of urticaria are the hives, and in the case of angioedema, in which the edema is located in the subcutaneous cellular tissue, the lesions are larger, so areas of skin distension are appreciated , normal or pink in color; the most frequent accompanying symptom is pruritus which is sometimes replaced, in angioedema, by a sensation of tension and burning in the area. The most frequent location is on the eyelids, lips, tongue, larynx (where they can also cause respiratory distress) and on the genitals.

Sometimes it can also associate general symptoms such as low-grade fever, gastrointestinal symptoms, headaches, etc.

In the case of hereditary angioedema, the appearance of edema in the face and extremities is typical, as well as episodes of laryngeal edema with respiratory compromise, and abdominal pain due to intestinal edema.

Diagnosis of angioedema

It is generally recognized by the appearance of typical lesions by visual inspection. Sometimes, as in chronic cases, a biopsy may be necessary, which will show edema in the dermis and subcutaneous cellular tissue, as well as vascular dilation and infiltration by cells such as mast cells.

The medical history can show us the triggering cause although it is not possible to find it in all cases. Sometimes, blood tests will be done looking for association with infection by germs such as the hepatitis virus , and even looking for parasites.

In the case of hereditary angioedema, the diagnosis is given by the presence of a family history and, in cases, the performance of laboratory tests to demonstrate the C1-inhibitor deficit.

Treat and avoid angioedema

The treatment of this disease is mainly medical:

• Antihistamines are useful in the case of the presence of itching.
• In the case of angioedema, the administration of steroids is also necessary.
• In the outbreak of hereditary angioedema, transfusion of plasma or C1 esterase inhibitor is helpful.

It may be useful to avoid the triggers if they are known (food, drugs …). In hereditary angioedema, it may be indicated in treatment with danazol in continuous therapy.