Research News
10 January 2025
New Research Highlights Advances in Understanding and Managing Hereditary Haemorrhagic Telangiectasia (HHT)
A newly published study titled “Hereditary haemorrhagic telangiectasia” provides a comprehensive look at this rare genetic vascular disorder. The paper delves into the underlying causes, key clinical features, and the latest advancements in treatment, offering hope for improved care and quality of life for individuals affected by this condition. Read the full study here.
What is Hereditary Haemorrhagic Telangiectasia?
Hereditary haemorrhagic telangiectasia (HHT), also known as Osler-Weber-Rendu syndrome, is a genetic vascular disorder inherited in an autosomal dominant pattern. It is caused by mutations in genes involved in the BMP (bone morphogenetic protein) signalling pathway, which plays a critical role in vascular development.
According to the study, 90% of HHT cases are linked to mutations in the ENG and ACVRL1 genes, while rarer cases involve SMAD4 and GDF2. These genetic abnormalities lead to fragile blood vessels and the formation of abnormal vascular structures known as telangiectases and arteriovenous malformations (AVMs).
Common symptoms and complications
The research highlights the most frequent symptoms and complications of HHT:
- Nosebleeds (epistaxis): Recurrent and often severe nosebleeds are the hallmark symptom in adults, frequently leading to iron deficiency anaemia.
- Gastrointestinal bleeding: This is caused by telangiectases in the gastrointestinal tract, further contributing to anaemia.
Serious complications arise from arteriovenous malformations (AVMs) in major organs, which include:
- Pulmonary AVMs: These cause abnormal blood flow (right-to-left shunting), increasing the risk of ischaemic stroke or brain abscesses.
- Systemic AVMs: These result in left-to-right shunting, potentially leading to high-output heart failure.
- AVMs in the liver and central nervous system can lead to a variety of severe and complex symptoms.
In children, isolated nosebleeds are the most common sign of HHT. However, in rare cases, significant complications may arise from large AVMs in the lungs or brain.
Diagnosis and treatment approaches
The article underscores the importance of early diagnosis and comprehensive management for HHT. The main goals of care include:
- Managing bleeding and anaemia: Control of recurrent epistaxis and gastrointestinal bleeding is essential, alongside the treatment of iron deficiency with or without anaemia.
- Screening for and managing AVMs: Early identification and treatment of AVMs in vital organs can prevent life-threatening complications.
- Genetic counselling: Assessing and supporting at-risk family members through genetic evaluation is a key component of care.
Promising new treatments
One of the most exciting areas of research in HHT is the development of systemic antiangiogenic therapies. These novel treatments aim to stabilise blood vessels, reduce bleeding, and improve overall outcomes. Although still under investigation, these therapies represent a significant step forward in the management of this complex condition.
Improving outcomes for people with HHT
While HHT is associated with increased morbidity, the study highlights that appropriate screening, early treatment of AVMs, and effective management of bleeding and anaemia can greatly enhance quality of life and long-term survival.
This research offers valuable insights for healthcare professionals, patients, and families affected by HHT. It also reinforces the importance of a multidisciplinary approach to care, integrating advances in genetics, medicine, and supportive therapies.