Osler-Weber-Rendu syndrome (hereditary haemorrhagic telangiectasia, HHT)

• What is Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia)
• Statistics on Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia)
• Risk Factors for Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia)
• Progression of Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia)
• Symptoms of Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia)
• Clinical Examination of Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia)
• How is Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia) Diagnosed?
• Prognosis of Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia)
• How is Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia) Treated?
• Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia) References

What is Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia)

Osler-Weber-Rendu Syndrome is a rare disorder that is genetic, via autosomal dominant inheritance. It is also known as hereditary haemorrhagic telangiectasia, Rendu-Osler-Weber syndrome, familial hemorrhagic angiomatosis, Osler disease, and heredofamilial angiomatosis.

The disorder is one of the blood vessels, which can cause excessive bleeding.

Statistics on Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia)

The worldwide prevalence is 1-2 cases per 100,000 population, with a much higher incidence in the Danish island of Fyn, the Dutch Antilles, and parts of France.

Race: The disease most commonly occurs in white patients, but it has been described in patients of Asian, African, and Arabic descent.

Sex: The syndrome occurs with equal frequency and severity in both sexes.

Age: The syndrome most often presents by the third decade of life but may be clinically silent.

The most common presentation is recurrent nosebleeds (epistaxis), which often develops prior to the second decade of life.

Pulmonary arteriovenous malformations may be congenital and is, therefore, diagnosed within the first year of life.

Risk Factors for Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia)

The disease is a genetically linked disease, with autosomal dominant inheritance.

Progression of Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia)

Because Osler-Weber-Rendu syndrome is an autosomal dominant disease, a family history of telangiectasia and recurrent bleeding in other family members is usually present. Symptoms vary depending on the area of involvement. The main areas of involvement are the nasal mucosa, skin, the GI tract, the pulmonary vasculature, and the brain.

How is Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia) Diagnosed?

1) A complete blood cell count

 

• haemoglobin may be decreased due to chronic bleeding and iron deficiency anaemia
• platelets may be normal or slighly increased
• white blood cell count should be within the reference range unless an infectious complication is present
• 2) Prothrombin time and activated partial prothrombin time should be normal, unless the liver is involved3) Arterial blood gas4) Imaging studies such as MRI, chest x-ray, CT and angiography
  5) Other tests such as a colonoscopy

  Prognosis of Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia)

  Many patients do not know that they have this condition until a family member is diagnosed with it. The disease is not life-threatening and is considered compatible with a long and full life.

  How is Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia) Treated?

  Bleeding in vital areas must be corrected surgically. Frequent or heavy nosebleeds (epistaxis) may be treated with electrocautery or laser surgery.

  Large collections of abnormal blood vessels (arterio-venous malformations) in the lungs may be deliberately “clotted off” in a procedure called “coiling” which is performed by an Interventional Radiologist. Some patients respond to therapy with the combined oral contraceptive pill, which can reduce bleeding episodes.

  Genetic counseling is recommended for prospective parents with a family history of hereditary hemorrhagic telangiectasia. Some strokes and high output heart failure can be prevented by clotting off the abnormal blood vessels in the lung (see above).

  Osler-Weber-Rendu Syndrome (Hereditary hemorrhagic telangiectasia) References

  [1] eMEDICINE
  [2] Kumar P, Clark M. Clinical Medicine. Fourth Ed. WB Saunders, 1998. p457-458
  [3] The Heriditary Haemorrhagic Telangiectasia Foundation International Website www.hht.org