U.S. flag

An official website of the United States government

Format

Send to:

Choose Destination

Telangiectasia, hereditary hemorrhagic, type 2(HHT2)

MedGen UID:
324960
Concept ID:
C1838163
Disease or Syndrome
Synonyms: ACVRL1-Related Hereditary Hemorrhagic Telangiectasia; HHT2; Osler Weber Rendu syndrome type 2; Telangiectasia, hereditary hemorrhagic, type II
 
Gene (location): ACVRL1 (12q13.13)
 
Monarch Initiative: MONDO:0010880
OMIM®: 600376

Disease characteristics

Excerpted from the GeneReview: Hereditary Hemorrhagic Telangiectasia
Hereditary hemorrhagic telangiectasia (HHT) is characterized by the presence of multiple arteriovenous malformations (AVMs) that lack intervening capillaries and result in direct connections between arteries and veins. The most common clinical manifestation is spontaneous and recurrent nosebleeds (epistaxis) beginning on average at age 12 years. Telangiectases (small AVMs) are characteristically found on the lips, tongue, buccal and gastrointestinal (GI) mucosa, face, and fingers. The appearance of telangiectases is generally later than epistaxis but may be during childhood. Large AVMs occur most often in the lungs, liver, or brain; complications from bleeding or shunting may be sudden and catastrophic. A minority of individuals with HHT have GI bleeding, which is rarely seen before age 50 years. [from GeneReviews]
Authors:
Jamie McDonald  |  David A Stevenson   view full author information

Additional description

From MedlinePlus Genetics
Hereditary hemorrhagic telangiectasia is a disorder that results in the development of multiple abnormalities in the blood vessels.

In the circulatory system, blood carrying oxygen from the lungs is normally pumped by the heart into the arteries at high pressure. The pressure allows the blood to make its way through the arteries to the smaller vessels (arterioles and capillaries) that supply oxygen to the body's tissues. By the time blood reaches the capillaries, the pressure is much lower. The blood then proceeds from the capillaries into veins, through which it eventually returns to the heart.

In hereditary hemorrhagic telangiectasia, some arterial vessels flow directly into veins rather than into the capillaries. These abnormalities are called arteriovenous malformations. When they occur in vessels near the surface of the skin, where they are visible as red markings, they are known as telangiectases (the singular is telangiectasia).

Without the normal buffer of the capillaries, the blood moves from the arteries at high pressure into the thinner walled, less elastic veins. The extra pressure tends to strain and enlarge these blood vessels, and may result in compression or irritation of adjacent tissues and frequent episodes of severe bleeding (hemorrhage). Nosebleeds are very common in people with hereditary hemorrhagic telangiectasia, and more serious problems may arise from hemorrhages in the brain, liver, lungs, or other organs.

Juvenile polyposis/hereditary hemorrhagic telangiectasia syndrome is a condition that involves both arteriovenous malformations and a tendency to develop growths (polyps) in the gastrointestinal tract. Hereditary hemorrhagic telangiectasia types 1, 2 and 3 do not appear to increase the likelihood of such polyps.

There are several forms of hereditary hemorrhagic telangiectasia, distinguished mainly by their genetic cause but with some differences in patterns of signs and symptoms. People with type 1 tend to develop symptoms earlier than those with type 2, and are more likely to have blood vessel malformations in the lungs and brain. Type 2 and type 3 may be associated with a higher risk of liver involvement. Women are more likely than men to develop blood vessel malformations in the lungs with type 1, and are also at higher risk of liver involvement with both type 1 and type 2. Individuals with any form of hereditary hemorrhagic telangiectasia, however, can have any of these problems.  https://medlineplus.gov/genetics/condition/hereditary-hemorrhagic-telangiectasia

Clinical features

From HPO
Clubbing
MedGen UID:
57692
Concept ID:
C0149651
Anatomical Abnormality
Broadening of the soft tissues (non-edematous swelling of soft tissues) of the digital tips in all dimensions associated with an increased longitudinal and lateral curvature of the nails.
Transient ischemic attack
MedGen UID:
853
Concept ID:
C0007787
Disease or Syndrome
A brief attack (from a few minutes to an hour) of cerebral dysfunction of vascular origin, with no persistent neurological deficit.
Hypertensive disorder
MedGen UID:
6969
Concept ID:
C0020538
Disease or Syndrome
The presence of chronic increased pressure in the systemic arterial system.
Spinal arteriovenous malformation
MedGen UID:
83876
Concept ID:
C0348023
Congenital Abnormality
Right-to-left shunt
MedGen UID:
98446
Concept ID:
C0428871
Finding
Pattern of blood flow in the heart that deviates from the normal circuit of the circulatory system from the right side of the heart to the left.
Hepatic arteriovenous malformation
MedGen UID:
101044
Concept ID:
C0520557
Congenital Abnormality
A benign vascular lesion characterized by the presence of a complex network of communicating arterial and venous vascular structures in the liver.
Gastrointestinal arteriovenous malformation
MedGen UID:
148166
Concept ID:
C0744321
Anatomical Abnormality
An anomalous configuration of blood vessels that shunts arterial blood directly into veins without passing through the capillaries and that is located in the gastrointestinal tract.
Gastrointestinal angiodysplasia
MedGen UID:
163130
Concept ID:
C0854242
Disease or Syndrome
Dysplasia affecting the vasculature of the gastrointestinal tract.
Cerebral arteriovenous malformation
MedGen UID:
214590
Concept ID:
C0917804
Congenital Abnormality
Arteriovenous malformations of the brain are tortuous, morphologically abnormal vascular channels between arteries and veins that lack an intervening capillary network, allowing high-pressure arterial blood from feeding arteries to shunt directly into the venous outflow system. These vascular malformations occur in approximately 15 per 100,000 persons and are a leading cause of hemorrhagic stroke in young adults and children (summary by Nikolaev et al., 2018).
Pulmonary arteriovenous malformation
MedGen UID:
341826
Concept ID:
C1857690
Anatomical Abnormality
Pulmonary arteriovenous malformation, a condition most commonly associated with hereditary hemorrhagic telangiectasia, is an abnormal communication between the pulmonary artery and pulmonary vein without an intervening capillary communication. HRCT images usually show a coarse spidery appearance of the peripheral vascular markings in the lungs. More specific findings are obtained in the pulmonary angiogram where the normally invisible capillary phase is replaced by irregular vascular channels bridging the peripheral branches of pulmonary arteries and veins.
Cerebral hemorrhage
MedGen UID:
423648
Concept ID:
C2937358
Pathologic Function
Hemorrhage into the parenchyma of the brain.
Pulmonary arterial hypertension
MedGen UID:
425404
Concept ID:
C2973725
Disease or Syndrome
Pulmonary hypertension is defined mean pulmonary artery pressure of 25mmHg or more and pulmonary capillary wedge pressure of 15mmHg or less when measured by right heart catheterisation at rest and in a supine position.
Hematemesis
MedGen UID:
6770
Concept ID:
C0018926
Sign or Symptom
The vomiting of blood.
Hematochezia
MedGen UID:
5481
Concept ID:
C0018932
Disease or Syndrome
The passage of fresh (red) blood per anus, usually in or with stools. Most rectal bleeding comes from the colon, rectum, or anus.
Cirrhosis of liver
MedGen UID:
7368
Concept ID:
C0023890
Disease or Syndrome
A chronic disorder of the liver in which liver tissue becomes scarred and is partially replaced by regenerative nodules and fibrotic tissue resulting in loss of liver function.
Melena
MedGen UID:
7523
Concept ID:
C0025222
Pathologic Function
The passage of blackish, tarry feces associated with gastrointestinal hemorrhage. Melena occurs if the blood remains in the colon long enough for it to be broken down by colonic bacteria. One degradation product, hematin, imbues the stool with a blackish color. Thus, melena generally occurs with bleeding from the upper gastrointestinal tract (e.g., stomach ulcers or duodenal ulcers), since the blood usually remains in the gut for a longer period of time than with lower gastrointestinal bleeding.
Seizure
MedGen UID:
20693
Concept ID:
C0036572
Sign or Symptom
A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.
Subarachnoid hemorrhage
MedGen UID:
11625
Concept ID:
C0038525
Disease or Syndrome
Hemorrhage occurring between the arachnoid mater and the pia mater.
Migraine
MedGen UID:
57451
Concept ID:
C0149931
Disease or Syndrome
Migraine is a chronic neurological disorder characterized by episodic attacks of headache and associated symptoms.
Ischemic stroke
MedGen UID:
215292
Concept ID:
C0948008
Disease or Syndrome
A stroke is an acute neurologic event leading to death of neural tissue of the brain and resulting in loss of motor, sensory and/or cognitive function. It is said to be the third leading cause of death in the United States. Gunel and Lifton (1996) noted that about 20% of strokes are hemorrhagic, resulting in bleeding into the brain. Ischemic strokes, resulting from vascular occlusion, account for the majority of strokes. Bersano et al. (2008) reviewed genetic polymorphisms that have been implicated in the development of stroke. Candidate genes include those involved in hemostasis (see, e.g., F5; 612309), the renin-angiotensin-aldosterone system (see, e.g., ACE; 106180), homocysteine (see, e.g., MTHFR; 607093), and lipoprotein metabolism (see, e.g., APOE; 107741). See also hemorrhagic stroke, or intracerebral hemorrhage (ICH; 614519).
Anemia
MedGen UID:
1526
Concept ID:
C0002871
Disease or Syndrome
A reduction in erythrocytes volume or hemoglobin concentration.
Polycythemia
MedGen UID:
18552
Concept ID:
C0032461
Disease or Syndrome
Polycythemia is diagnosed if the red blood cell count, the hemoglobin level, and the red blood cell volume all exceed the upper limits of normal.
Spontaneous, recurrent epistaxis
MedGen UID:
816045
Concept ID:
C3809715
Finding
Dyspnea
MedGen UID:
3938
Concept ID:
C0013404
Sign or Symptom
Difficult or labored breathing. Dyspnea is a subjective feeling only the patient can rate, e.g., on a Borg scale.
Brain abscess
MedGen UID:
2335
Concept ID:
C0006105
Disease or Syndrome
A collection of pus, immune cells, and other material in the brain.
Tongue telangiectasia
MedGen UID:
871382
Concept ID:
C4025878
Anatomical Abnormality
Telangiectasia (that is, the presence of small dilated superficial blood vessels) of the tongue.
Cyanosis
MedGen UID:
1189
Concept ID:
C0010520
Sign or Symptom
Bluish discoloration of the skin and mucosa due to poor circulation or inadequate oxygenation of arterial or capillary blood.
Conjunctival telangiectasia
MedGen UID:
66780
Concept ID:
C0239105
Disease or Syndrome
The presence of small (ca. 0.5-1.0 mm) dilated blood vessels near the surface of the mucous membranes of the conjunctiva.
Facial telangiectasia
MedGen UID:
488948
Concept ID:
C0858684
Finding
Telangiectases (small dilated blood vessels) located near the surface of the skin of the face.
Gastrointestinal telangiectasia
MedGen UID:
451085
Concept ID:
C1619711
Disease or Syndrome
Telangiectasia affecting the gastrointestinal tract.
Nail bed telangiectasia
MedGen UID:
373904
Concept ID:
C1838167
Finding
Telangiectases in the area of the nails.
Lip telangiectasia
MedGen UID:
347522
Concept ID:
C1857697
Finding
Telangiectasia (that is, the presence of small dilated superficial blood vessels) of the lips.
Palate telangiectasia
MedGen UID:
387887
Concept ID:
C1857699
Finding
The presence of small (ca. 0.5-1.0 mm) dilated blood vessels near the surface of the mucous membranes of the palate.
Fingerpad telangiectases
MedGen UID:
396091
Concept ID:
C1861248
Finding
Telangiectasia (small dilated blood vessels) located in the fingerpads at the tips of the fingers.
Palmar telangiectasia
MedGen UID:
866602
Concept ID:
C4020948
Anatomical Abnormality
The presence of telangiectases on the skin of palm of hand.
Nasal mucosa telangiectasia
MedGen UID:
871359
Concept ID:
C4025853
Finding
Telangiectasia of the nasal mucosa.
Oral cavity telangiectasia
MedGen UID:
871381
Concept ID:
C4025877
Finding
Presence of telangiectases in the oral cavity.
Choriocapillaris atrophy
MedGen UID:
477389
Concept ID:
C3275758
Finding
Atrophy of the capillary lamina of choroid.

Professional guidelines

PubMed

Barth T, Zeman F, Helbig H, Gamulescu MA
Int Ophthalmol 2018 Feb;38(1):191-198. Epub 2017 Jan 21 doi: 10.1007/s10792-017-0447-0. PMID: 28108904

Suggested Reading

PubMed

Shovlin CL, Guttmacher AE, Buscarini E, Faughnan ME, Hyland RH, Westermann CJ, Kjeldsen AD, Plauchu H
Am J Med Genet 2000 Mar 6;91(1):66-7. doi: 10.1002/(sici)1096-8628(20000306)91:1<66::aid-ajmg12>3.0.co;2-p. PMID: 10751092

Supplemental Content

Table of contents

    Clinical resources

    Practice guidelines

    • PubMed
      See practice and clinical guidelines in PubMed. The search results may include broader topics and may not capture all published guidelines. See the FAQ for details.

    Recent activity

    Your browsing activity is empty.

    Activity recording is turned off.

    Turn recording back on

    See more...