Hereditary Angioedema

Publication Date: June 1, 2013

Key Points

Key Points

Most cases of hereditary angioedema (HAE) result from a deficiency of the serine protease inhibitor, C1 inhibitor (C1INH). (, LB)
562

HAE is caused by mutations in the C1INH gene, resulting in a C1INH functional deficiency. (, LB)
562

HAE is an autosomal dominant disease. Most patients with HAE have a positive family history of angioedema. (, A)
562

Two forms of HAE, which are indistinguishable clinically, can be diagnosed by laboratory findings: type I HAE presents with low C1INH antigenic and functional levels, whereas type II HAE presents with normal C1INH antigenic levels but decreased C1INH functional levels. (, A )
562

Diagnosis of type I or type II HAE requires evidence of low C1INH antigenic or functional levels, as well as decreased C4 levels and generally normal C1q levels. (, A)
562

Onset of swelling in HAE most often begins during childhood and frequently worsens around puberty. (, C )
562

HAE is characterized by relatively prolonged attacks of angioedema involving the extremities, genitourinary tract, abdomen, face, oropharynx or larynx. (, C )
562

The primary mediator of swelling in HAE is bradykinin. (, A)
562

Disease severity in HAE is highly variable, characterized by episodic rather than continuous swelling. (, D )
562

A precipitating cause for most episodes of HAE attacks is unknown, but stress and trauma have been clearly recognized as precipitants. (, D)
562

Attacks of swelling in HAE generally involve the extremities, abdomen, genitourinary tract, face, oropharynx, or larynx and follow a stereotypical pattern in which the swelling worsens over 24 hours, peaks, then slowly resolves over the following 48-72 hours. (, A )
562

Attacks of HAE may be preceded by a prodrome. (, C )
562

HAE attacks are associated with significant potential morbidity and potential mortality. (, A)
562

Optimal management of HAE depends on early identification of patients. (, )
562

Diagnosis

...agnosis...

...1. Complement Levels in the Diagnosis of H...


...gure 1. Recurrent Angioedema – Diagnosti...


Prevention

...evention...

...ment with replacement plasma-derived C1INH...


...agents for treatment of patients w...


...low to moderate doses of anabolic and...


...reatment with antifibrinolytic agents p...


...phylaxis can be achieved with fresh...


...need for long-term HAE prophylaxis...


...dose and effectiveness of long-term proph...


...ategies such as avoidance of ACE-Is, avoidance...


...of action of 17α-alkylated androg...


Pregnancy might be associated with an...


Treatment

...eatment

...h HAE-specific agent. Evidence from double-...


...t of HAE attacks may involve symptomatic treatment...


...plasma is often effective in abrogatin...


Neither anabolic androgens nor antifibrinolyt...


...ephrine, corticosteroids and antihistamines are NO...


Figure 2. HAE Treatment Algorithm


...HAE-Specific AgentsHaving trouble viewing table...


...Commonly Used for Long-term HAE Prophylaxis...


Special Cases

...ial Cases...

...th normal C1INH level...

...amilial recurrent angioedema characte...

...eds with HAE with normal C1INH leve...

...normal C1INH levels may be caused by...

Drugs developed for patients with HAE with reduce...


...red C1INH Deficiency...

...l characteristics of angioedema episodes i...

...uired C1INH deficiency involves demonstration...

...deficiency results from enhanced...

...d C1INH deficiency might be associated...

...of acquired C1INH deficiency is similar to...


...I–Associated Angioed...

...associated with angioedema in approx...

The management of ACE-I (or ARB)–asso...

...he angioedema associated with ACE-Is is likely...

...recurrent angioedema exists in patients wh...