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Hereditary hemorrhagic telangiectasia (HHT), also known as Osler-Weber-Rendu syndrome, is a genetic disorder characterized by abnormal blood vessel formation, leading to fragile, dilated blood vessels called telangiectasias and arteriovenous malformations (AVMs). Here's an overview of its symptoms, treatment plan, diagnosis, and testing.

1. Nosebleeds (epistaxis): Recurrent nosebleeds, often starting in childhood and becoming more frequent with age, are a hallmark symptom of HHT.
2. Telangiectasias: Small, red or purple blood vessels visible on the skin, particularly on the face, lips, fingertips, and mucous membranes (e.g., inside the nose, mouth, and gastrointestinal tract).
3. AVMs: Abnormal connections between arteries and veins that may develop in various organs, most commonly the lungs, liver, brain, and gastrointestinal tract, leading to symptoms such as:
   • Shortness of breath or difficulty breathing: Due to pulmonary AVMs.
   • Liver complications: Such as cirrhosis, portal hypertension, or liver failure due to hepatic AVMs.
   • Neurological symptoms: Such as headaches, seizures, or stroke-like symptoms due to cerebral AVMs.
   • Gastrointestinal bleeding: Due to gastrointestinal AVMs, which can cause blood in the stool or anemia.

1. Management of symptoms: Treatment focuses on controlling symptoms and complications associated with HHT, such as:
   • Nosebleed management: Including nasal saline sprays, humidification, nasal packing, and cauterization procedures.
   • Monitoring and treatment of AVMs: Depending on the location and severity, treatment may involve embolization (blocking blood flow to the AVM), surgery, or other interventional procedures.
   • Blood transfusions: For severe anemia resulting from recurrent bleeding episodes.
2. Iron supplementation: To address iron deficiency anemia resulting from chronic bleeding.
3. Anticoagulation management: Due to the risk of clot formation in certain individuals with HHT, careful management of anticoagulant medications may be necessary.
4. Genetic counseling: HHT is an inherited disorder, and genetic counseling can provide information about the risk of passing the condition to offspring and available reproductive options.

1. Clinical evaluation: A healthcare provider will inquire about symptoms, family history, and perform a physical examination to identify characteristic signs of HHT, such as nosebleeds, telangiectasias, and signs of organ involvement.
2. Imaging studies: Imaging tests such as contrast-enhanced CT scans, MRI, or Doppler ultrasound may be performed to evaluate for the presence of AVMs in various organs.
3. Genetic testing: Molecular genetic testing can identify mutations in genes associated with HHT, including ENG (endoglin), ACVRL1 (ALK1), and SMAD4. However, not all individuals with HHT will have identifiable mutations.
4. Endoscopy: Upper endoscopy or colonoscopy may be performed to evaluate for gastrointestinal telangiectasias or AVMs in individuals with symptoms such as gastrointestinal bleeding or iron deficiency anemia.