Hereditary Hemorrhagic Telangiectasia – Symptoms and Causes
Overview
Hereditary Hemorrhagic Telangiectasia (HHT), also known as Osler-Weber-Rendu disease, is an inherited condition. It creates unusual connections between arteries and veins called arteriovenous malformations (AVMs).
These abnormal connections can develop in multiple areas of the body, including the skin, nose, digestive tract, lungs, brain, and liver.
The most common symptom is frequent, unexplained nosebleeds that can occur daily. These nosebleeds, along with bleeding in the digestive system, may lead to iron deficiency anemia and reduced quality of life.
Key facts about HHT:
- It’s passed from parents to children
- Severity varies widely, even within families
- AVMs may grow larger over time
- Bleeding AVMs can cause serious health problems
If you have HHT and are planning a family, consider genetic testing for your children. The condition can affect them even without obvious symptoms. Early detection helps manage potential complications before they become serious health risks.
Signs and Warning Signs
Nosebleeds are a common sign of HHT, often occurring daily and beginning during childhood. Tiny red spots or lacy red vessels (telangiectasias) typically appear on the lips, face, fingertips, tongue, and inside the mouth.
People with HHT may develop iron deficiency anemia from blood loss through the nose or digestive tract. Breathing difficulties and headaches are also frequent complaints.
More serious symptoms include:
- Seizures
- Brain abscess (infection with pus)
- Strokes
- Bone infection (osteomyelitis)
These symptoms vary in severity among patients. Some experience mild signs, while others face more serious complications.
Causes
HHT results from genetic changes passed from parents to children. This condition follows an autosomal dominant pattern of inheritance.
What does this mean for families? If one parent has HHT, each child faces a 50% chance of inheriting the condition. Similarly, if you have HHT, each of your children has the same 50% probability of receiving the affected gene from you.
Risk Factors
The main risk factor for hereditary hemorrhagic telangiectasia (HHT) is having a family history of the condition. This genetic disorder follows an autosomal dominant inheritance pattern, which means:
- A person only needs to inherit one copy of the mutated gene from one parent to develop the condition
- Each child of an affected parent has a 50% chance of inheriting HHT
- The condition does not skip generations
Family history is crucial in identifying those at risk for HHT. Individuals with a parent who has this condition should consider genetic testing and evaluation, especially before symptoms appear.
While family history is the primary risk factor, some important points to note:
- Genetic Mutations: Specific gene mutations cause different types of HHT.
- No Known Prevention: Since HHT is genetic, there are no known ways to prevent inheritance.
- Equal Risk: The condition affects males and females equally.
People with a family history of HHT should consult healthcare providers about screening, even if they don’t have symptoms yet.
