Hereditary Hemorrhagic Telangiectasia

The most characteristic lesions of hereditary hemorrhagic telangiectasia are small red-to-violet telangiectatic lesions on the face, lips, oral and nasal mucosa, and tips of the fingers and toes. Similar lesions may be present throughout the mucosa of the gastrointestinal (GI) tract, resulting in recurrent GI bleeding. Patients may experience recurrent, profuse nosebleeds.

Some patients have pulmonary arteriovenous malformations (AVMs). These AVMs may cause significant right-to-left shunts, which can result in dyspnea, fatigue, cyanosis, or erythrocytosis. However, the first sign of the presence of AVMs may be a brain abscess, transient ischemic attack Transient Ischemic Attack (TIA) A transient ischemic attack (TIA) is focal brain ischemia that causes sudden, transient neurologic deficits and is not accompanied by permanent brain infarction (eg, negative results on diffusion-weighted... read more , or stroke Overview of Stroke Strokes are a heterogeneous group of disorders involving sudden, focal interruption of cerebral blood flow that causes neurologic deficit. Strokes can be Ischemic (80%), typically resulting... read more as a result of infected or noninfected emboli. Cerebral or spinal AVMs occur in some families and may cause subarachnoid hemorrhage Subarachnoid Hemorrhage (SAH) Subarachnoid hemorrhage is sudden bleeding into the subarachnoid space. The most common cause of spontaneous bleeding is a ruptured aneurysm. Symptoms include sudden, severe headache, usually... read more , seizures Seizure Disorders A seizure is an abnormal, unregulated electrical discharge that occurs within the brain’s cortical gray matter and transiently interrupts normal brain function. A seizure typically causes altered... read more , or paraplegia. Hepatic AVMs may lead to liver failure Acute Liver Failure Acute liver failure is caused most often by drugs and hepatitis viruses. Cardinal manifestations are jaundice, coagulopathy, and encephalopathy. Diagnosis is clinical. Treatment is mainly supportive... read more and high output heart failure Heart Failure (HF) Heart failure (HF) is a syndrome of ventricular dysfunction. Left ventricular (LV) failure causes shortness of breath and fatigue, and right ventricular (RV) failure causes peripheral and abdominal... read more .

Chronic iron deficiency anemia Iron Deficiency Anemia Iron deficiency is the most common cause of anemia and usually results from blood loss; malabsorption, such as occurs in celiac disease, is a much less common cause. Symptoms are usually nonspecific... read more is commonly present.

Diagnosis of hereditary hemorrhagic telangiectasia is based on the finding of characteristic arteriovenous malformations on the face, mouth, nose, palms, digits, and/or internal organs in the context of epistaxis and family history. The Curaçao criteria include the following:

Hereditary hemorrhagic telangiectasia is definite if 3 of these criteria are met and possible if 2 are met (1, 2 Diagnosis references Hereditary hemorrhagic telangiectasia is a hereditary disorder of vascular malformation transmitted as an autosomal dominant trait affecting men and women. (See also Overview of Vascular Bleeding... read more ).

Sometimes endoscopy or angiography or both are needed. Laboratory findings are usually normal except for iron deficiency anemia Iron Deficiency Anemia Iron deficiency is the most common cause of anemia and usually results from blood loss; malabsorption, such as occurs in celiac disease, is a much less common cause. Symptoms are usually nonspecific... read more in many patients.

Testing for the ENG,ACVRL1, and SMADH4 (MADH4) mutations may be helpful in some patients with atypical features or for screening asymptomatic family members.

If a family history of pulmonary, hepatic, or cerebral arteriovenous malformations exists, screening at puberty and at the end of adolescence with pulmonary CT, hepatic CT, and cerebral MRI is recommended. Screening also involves checking for iron deficiency anemia due to the chronic blood loss. Screening may also include blood tests for the gene mutations mentioned above.

Treatment for most patients is supportive, but accessible telangiectasias (eg, in the nose or gastrointestinal tract via endoscopy) may be treated with laser ablation. Arteriovenous malformations in the lungs can be treated by surgical resection or coil embolization.

Liver lesions may not be amenable to surgical or endovascular treatment. Measurement of serum ammonia level may help assess the degree of hepatic shunting of blood (1 Treatment references Hereditary hemorrhagic telangiectasia is a hereditary disorder of vascular malformation transmitted as an autosomal dominant trait affecting men and women. (See also Overview of Vascular Bleeding... read more ).

Repeated blood transfusions Blood Products Whole blood can provide improved oxygen-carrying capacity, volume expansion, and replacement of clotting factors and was previously recommended for rapid massive blood loss. However, because... read more may be needed.

Many patients require continuous oral iron therapy to replace iron lost due to repeated mucosal bleeding (see treatment of Iron Deficiency Anemia Treatment Iron deficiency is the most common cause of anemia and usually results from blood loss; malabsorption, such as occurs in celiac disease, is a much less common cause. Symptoms are usually nonspecific... read more ). Many patients also require parenteral (IV) iron, and sometimes recombinant erythropoietin is necessary.

Treatment with medications that inhibit fibrinolysis, such as aminocaproic acid or tranexamic acid, may be beneficial.

Treatment with medications that inhibit angiogenesis such as bevacizumab, pomalidomide, thalidomide, or pazopanib can reduce the number and density of abnormal vessel growth (2 Treatment references Hereditary hemorrhagic telangiectasia is a hereditary disorder of vascular malformation transmitted as an autosomal dominant trait affecting men and women. (See also Overview of Vascular Bleeding... read more ). In addition, bevacizumab has been shown to reduce the incidence of nasal and gastrointestinal bleeding (3, 4, 5 Treatment references Hereditary hemorrhagic telangiectasia is a hereditary disorder of vascular malformation transmitted as an autosomal dominant trait affecting men and women. (See also Overview of Vascular Bleeding... read more ).

To avoid paradoxical embolization of particulate matter to the brain through pulmonary arteriovenous malformations, all IV fluids need to given through a filter.