How much do you know about vascular edema?

The common cause of vascular edema is not allergy, but C1 inhibitor deficiency. Because it recurs and can affect the mucosa, it may be fatal due to laryngeal edema if ignored. There is currently no treatment for acute attacks in China. Therefore, a certain amount of common sense can play a preventive role in this disease.

Understanding Vascular Edema

It refers to localized swelling that occurs in loose tissue areas (such as eyelids, lips, tongue, external genitalia, hands and feet, etc.), with unclear boundaries, skin color or light red, shiny surface, elastic to the touch, and mostly single.

How is it different from the wheals of urticaria?

Wheals are variable, with itching as the main symptom, which disappears within 24 hours. Vascular edema, on the other hand, causes obvious pain, which is localized and lasts for a long time, often for more than 3 days.

What are the causes of vascular edema?

You may think of allergies first, but literature data shows that except for idiopathic factors, allergic factors only account for 16%, ranking second. The first is caused by complement C1 inhibitor deficiency, accounting for 25%.

In what cases should allergic angioedema be considered?

Allergies should be considered if they occur within 20-60 minutes after ingestion, while the possibility of allergies occurring after 24 hours is small. If they are caused by exercise after ingestion, food dependence and exercise induction should be considered, which is common in wheat. Allergies may occur after exposure to a certain environment, contact with a certain allergenic substance, or a certain drug, such as aspirin, ACEI, etc.

Understanding Hereditary Vascular Edema

C1 inhibitor deficiency causes vascular edema, which is hereditary in 93% of cases and is autosomal dominant. It is characterized by recurrent attacks, non-concave, asymmetric, and non-itching. It can be self-limited and may involve the mucosa, such as laryngeal edema and gastrointestinal obstruction.

What causes it?

Minor trauma, even the pressure of carrying a bag, can cause it, which can easily be mistaken for contact allergy; minor surgery such as tooth extraction; medications such as estrogen and ACEI; emotional influences; infection, etc.

Laboratory inspection:

Complementary examinations include C4, C1 inhibitor function, C1 inhibitor content, and C1q. C1q is used to distinguish whether the condition is acquired. If normal, it is mostly hereditary. If the C1q level is low (due to consumption), acquisition is considered.