Hereditary angioedema | |
---|---|
Other names | Hereditary angioneurotic edema (HANE),[1] familial angioneurotic edema[2] |
Swollen right hand during a hereditary angioedema attack. | |
Specialty | Hematology |
Symptoms | Recurrent attacks of severe swelling[3] |
Usual onset | Childhood[3] |
Duration | Attacks last a few days[3] |
Types | Type I, II, III[3] |
Causes | Genetic disorder (autosomal dominant)[3] |
Diagnostic method | Measuring C4 and C1-inhibitor levels.[2] |
Differential diagnosis | Intestinal obstruction, other types of angioedema[2] |
Prevention | C1 inhibitor[1] |
Treatment | Supportive care, medications[1] |
Medication | C1 inhibitor, ecallantide, icatibant[1] |
Prognosis | 25% risk of death if airway involved (without treatment)[2] |
Frequency | ~1 in 50,000[3] |
Hereditary angioedema (HAE) is a disorder that results in recurrent attacks of severe swelling.[3] The swelling most commonly affects the arms, legs, face, intestinal tract, and airway[3] and is usually not itchy.[2] If the intestinal tract is affected, abdominal pain and vomiting may occur.[1] Swelling of the airway can result in its obstruction.[1] Without preventive treatment, attacks typically occur every two weeks and last for a few days.[3]
There are three main types of HAE.[3] Types I and II are caused by a mutation in the SERPING1 gene, which makes the C1 inhibitor protein, while type III is often due to a mutation in the F12 (factor XII) gene.[3] The result is increased levels of bradykinin, which promotes swelling.[3] The condition may be inherited from a person's parents in an autosomal dominant manner or occur as a new mutation.[3] Triggers for an attack may include minor trauma or stress, but attacks often occur without any obvious preceding event.[3] Diagnosis of types I and II is based on measurement of C4 and C1-inhibitor levels.[2]
Management of HAE involves efforts to prevent attacks and the treatment of attacks if they occur.[1] During an attack, supportive care such as intravenous fluids and airway support may be required.[1] C1 inhibitor medications can be used for both prevention and treatment, while ecallantide and icatibant can be used to treat acute attacks.[1]
HAE affects approximately 1 in 50,000 people.[3] The condition is typically first noticed in childhood.[3] Type I and II affected females and males equally,[4] while type III affects females more often than males.[2] When the airway is involved, without treatment, the risk of death is about 25%.[2] With treatment, outcomes are generally good.[2] The condition was first described in 1888 by Canadian physician William Osler.[5]
References
edit- ^ a b c d e f g h i "Hereditary angioedema". GARD. 2017. Archived from the original on 4 July 2017. Retrieved 10 July 2017.
- ^ a b c d e f g h i "Orphanet: Hereditary angioedema". www.orpha.net. August 2011. Archived from the original on 9 October 2015. Retrieved 10 July 2017.
- ^ a b c d e f g h i j k l m n o p Reference, Genetics Home (5 July 2017). "hereditary angioedema". Genetics Home Reference. Archived from the original on 10 July 2017. Retrieved 10 July 2017.
- ^ "Hereditary Angioedema - NORD (National Organization for Rare Disorders)". NORD (National Organization for Rare Disorders). 2008. Archived from the original on 14 July 2017. Retrieved 10 July 2017.
- ^ Levin, Alex V.; Enzenauer, Robert W. (2017). The Eye in Pediatric Systemic Disease. Springer. p. 71. ISBN 9783319183893. Archived from the original on 2017-09-10.