Knowledge about hereditary angioedema

Hereditary angioedema is something we are unfamiliar with. Actually, this is a medical term. The focus is on edema, which we all understand very well, so let's take a look at the clinical manifestations and treatment of this disease.

Hereditary angioedema is an autosomal recessive disease that can occur at any age but is more common in early adulthood. The cause of the disease is a decrease or functional defect in the C1 lipase inhibitor (an α2 globulin) in the patient's serum, resulting in overactivation of C1, uncontrolled cleavage of C4 and C2, and an increase in the production of complement kinins, which increases microvascular permeability and causes edema.

Recurrent episodes of acute mucocutaneous edema. ① Recurrent episodes of localized subcutaneous edema of the face, neck, trunk, and limbs. It often occurs when there is minor local trauma. The onset is sudden, with no local pain, itching, or obvious redness, and it usually lasts for 48 to 72 hours before spontaneously resolving. ② Edema of the laryngeal, respiratory and digestive tract mucosa may occur. Symptoms include difficulty breathing, hoarseness, suffocation, abdominal pain, diarrhea, nausea, and vomiting.

Auxiliary examination:

① Serum C1 lipase assay: low level. A small number (10%-20%) may also be higher than normal, but the electrophoretic mobility is slowed down.

②C4 and C2 determination: When the disease occurs, both C4 and C2 are significantly reduced; when the disease is not severe, C2 is normal but C4 is still low.

③50% complement hemolytic unit (CH50) is reduced.

Treatment measures:

1. Transaminase, 1-3 g/day, orally in 3 divided doses.

2. Antihistamines, such as chlorpheniramine, diphenhydramine, deschlorobenzene, etc.

3. Corticosteroids can be taken orally with prednisone, intravenously with hydrocortisone, or orally or intravenously with dexamethasone.

4. Infusion of normal human plasma can temporarily supplement C1 lipase inhibitor.

5. Apply local cold wet compress.

6. If laryngeal edema occurs, immediately give 0.5 mg of epinephrine or 15 mg of ephedrine intramuscularly, and consider tracheotomy.

7. Anabolic hormones, such as danazol, dehydromethyltestosterone, stanozolol, etc., can induce the synthesis of C1 lipase inhibitors, thereby preventing attacks.

After learning about hereditary angioedema, we know its clinical manifestations, its concept, as well as its auxiliary examinations and treatment measures. We all have a new understanding of it. I believe that everyone will be able to overcome it and regain health.