Hereditary Hemorrhagic Telangiectasia: More Than a Nosebleed

A 50 year-old Caucasian male had a spontaneous episode of epistaxis (nose bleed) while sitting at his desk. Despite cold compresses and pinching his nose while leaning forward, the bleeding continued. He was seen in an ER and treated with nasal packing. The episode resolved after several days. Past medical history was unremarkable. His only medication was Viagra.

One week later, he had a second spontaneous episode of epistaxis. He was examined by an ENT physician who visualized arteriovenous malformations in his nasal mucosa. He was treated with cauterization.

On further questioning, the patient recalled that his father also had several episodes of epistaxis. One week after the patient's cauterization, his 30 year-old son had a spontaneous episode of epistaxis. Due to this family history, the patient had MRI of the chest and abdomen which were unremarkable.

Hereditary Hemorrhagic Telangiectasia (HHT, or Osler-Weber-Rendu Syndrome) is an inherited vascular dysplasia. The main features are epistaxis, mucocutaneous telangiectasias, gastrointestinal bleeding and iron-deficiency anemia.

HHT is definitively diagnosed by the triad of epistaxis, telangiectasia and a suitable family history. However, the triad occurs in only a small number of cases; consequently, HHT can be presumptively diagnosed with only two criteria present. If less than two criteria, HHT is unlikely.

HHT is inherited in an autosomal dominant manner; consequently, one half of children (sons or daughters) of an affected parent inherit the disease. Many affected individuals are not diagnosed and at risk of complications of hemorrhage of visceral arteriovenous malformations, especially in the pulmonary or cerebral circulations.

There is no agreement on the number of episodes or severity of epistaxis necessary to satisfy a diagnosis of HHT. Epistaxis should occur spontaneously on more than one occasion.

Two HHT disease-causing genes (endoglin and ALK-1) have been identified. However, for the majority of patients, only a clinical diagnosis can be made.

Bevacizumab, an anti-VEGF antibody (vascular endothelial growth factor) has been shown to be effective in case reports, however the effects are not permanent and maintenance therapy may be required.

It has been hypothesized that Robert Louis Stevenson (RLS) may have died at age 44 years due to HHT. He had a chronic illness manifested by respiratory complaints, recurrent pulmonary hemorrhage and a probable cerebral hemorrhage. It would also explain his mother's death at age 38 years due to an apparent stroke. In the era of molecular genetics, it might be possible to examine hair or tissue from RLS to prove the case.