Definition of the disease
Hereditary angioedema (HAE) is a genetic disease characterized by the occurrence of transient and recurrent submucosal and / or subcutaneous edema resulting in abdominal pain and / or inflammation.
- Bradykinin-Induced Hereditary Angioedema
- Hereditary non-histamine-induced angioedema
- Familial angioneurotic edema
- Hereditary angioneurotic edema
The prevalence is estimated at 1 / 100,000. The onset of the manifestations of the disease can occur at any age, but is most common during childhood or adolescence. Need to know more information you can search as well.
Patients present with white, circumscribed, non-pruritic edemas that remain for a period of 48 to 72 hours and recur with variable frequency. Edema can affect the digestive system resulting in a clinical image similar to that observed in intestinal obstruction syndromes, sometimes associated with ascites and hypovolemic shock. Laryngeal edema can be life-threatening, with a risk of death of 25% of cases, in the absence of appropriate treatment.
Three types of HAE have been described. Types 1 and 2 are caused by abnormalities in the SERPING1 gene , which encodes the C1-plasma protease inhibitor (C1-INH). Type 1 is caused by a deletion or the expression of a truncated transit, leading to a quantitative defect in C1-INH. Type 2 is caused by point mutations, leading to a qualitative defect in C1-INH. Transmission is autosomal dominant and affects heterozygotes in most cases. Edema is caused by an increase in the permeability of the blood vessels, in response to high levels of bradykinin, as a result of a deficiency of C1-INH. HAE type 3 predominantly affects women, with pregnancy and the use of estrogen-containing oral contraceptives being precipitating factors. Type 3 is not caused by a C1-INH deficiency, but is associated with increased quininogenase activity, which causes elevated levels of bradykinin. Some cases have been associated with coagulation factor XII gain-of-function mutations, but other genetic abnormalities remain to be identified. Check For more information https://wearehae.co.uk/.
The diagnosis of HAE types 1 and 2 depends on the measurement of the concentration of C4 and on the quantitative and functional analyzes of C1-INH. Type 3 diagnosis is established by clinical data and possible family history. C4 and C1-INH levels are normal. Analysis of mutations in the F12 gene can be proposed, but they are present in only 15% of patients.
Management and treatment
Corticosteroid, antihistamine, or adrenaline treatments are not effective. In Europe, moderate episodes should be treated with subcutaneous icatibant (a bradykinin receptor antagonist) or intravenous administration of C1-concentrated inhibitor. Prophylactic treatment with tranexamic acid or attenuated androgens can be proposed for patients with frequent episodes.
The prognosis is good for patients who have been diagnosed and who have access to adequate treatment for ear-nose-throat edema. Its significant morbidity may be associated with digestive involvement, which can lead to pain and bed rest for at least three days after the episode.