From the Guidelines
Hereditary hemorrhagic telangiectasia (HHT) should be managed according to the Second International HHT Guidelines, which provide evidence-based recommendations for the diagnosis and management of HHT-related symptoms and complications. The guidelines, developed using the AGREE II framework and GRADE methodology, cover six priority topic areas: epistaxis, gastrointestinal bleeding, anemia and iron deficiency, liver VMs, pediatric care, and pregnancy and delivery 1. Key recommendations include:
- Controlling bleeding episodes and preventing serious complications
- Screening for internal arteriovenous malformations (AVMs) in organs like the lungs, brain, and liver
- Using treatments such as moisturizing nasal sprays, topical medications like tranexamic acid, laser therapy, or surgical interventions for nosebleeds
- Managing anemia with iron supplementation or blood transfusions
- Embolization procedures, surgery, or medications to address internal AVMs. The guidelines highlight new evidence in existing topics and provide guidance in new areas, including anemia, pediatrics, and pregnancy and delivery 1. Regular follow-up with specialists familiar with HHT is essential for optimal management, as the condition is characterized by the presence of vascular malformations (VMs) that can result in chronic bleeding, acute hemorrhage, and complications from shunting through VMs 1. Overall, the management of HHT should prioritize controlling symptoms, preventing complications, and improving quality of life, with a focus on individualized care and regular monitoring 1.
From the Research
Definition and Characteristics of Hereditary Hemorrhagic Telangiectasia
- Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal dominant disorder characterized by vascular malformations 2, 3, 4, 5, 6.
- It is also known as Osler-Rendu-Weber syndrome or Osler-Weber-Rendu syndrome 2, 4, 5.
- The disorder is caused by mutations in genes involved in the transforming growth factor-β signaling pathway, leading to abnormal blood vessel formation 2, 5.
Clinical Manifestations and Complications
- Common manifestations of HHT include telangiectasia on the skin and mucous membranes, and epistaxis (nosebleeds) is a hallmark symptom 2, 4, 5.
- Visceral arteriovenous malformations (AVMs) can occur in the lungs, liver, brain, and gastrointestinal tract, leading to life-threatening complications such as hemorrhage, embolism, and brain abscess 2, 5, 6.
- Anemia can occur due to chronic blood loss from vascular malformations 4.
Diagnosis and Screening
- Diagnosis of HHT requires the presence of at least three out of four clinical criteria, known as the Curaçao criteria: epistaxis, telangiectasias, visceral involvement, and a family history of HHT in a first-degree relative 4, 5.
- Molecular genetic testing can be used to establish the genetic subtype of HHT and for early diagnosis to allow for appropriate screening and preventive treatment 5.
- Routine screening for AVMs is indicated in patients diagnosed with HHT to prevent severe complications 6.
Management and Treatment
- Management of HHT involves a multidisciplinary approach, including interventional radiology techniques, surgery, and medical therapy 2, 3, 6.
- Embolization of the afferent arteries of AVMs is a minimally invasive procedure with high efficacy and low morbidity and mortality 6.
- Other therapeutic modalities include surgery (resection) and stereotactic radiosurgery (using radiation) 6.