Osler-Weber-Rendu disease (Hereditary Hemorrhagic Telangiectasia, HHT) is a rare autosomal dominant disorder that results in vascular dysplasia, causing abnormal blood vessel development throughout the body and a predisposition to bleeding. We present a case of a 27-year-old female with hypoxemia, recurrent spontaneous epistaxis, and pulmonary arteriovenous malformations (AVMs), diagnosed through radiological workup. She was successfully treated with embolization of the AVM.
Osler-Weber-Rendu Syndrome, or Hereditary Hemorrhagic Telangiectasia (HHT), is a genetic disorder that causes abnormal blood vessel formation, leading to the development of telangiectasias and arteriovenous malformations (AVMs) in both mucocutaneous structures and various organs such as the lungs, liver, brain, and gastrointestinal system. Its prevalence ranges from 1 in 5,000 to 1 in 8,000, with an estimated 85,000 affected individuals globally. As an autosomal dominant condition, it affects males and females equally, although some studies suggest that females may experience more severe liver and pulmonary involvement.
There are three major types of HHT: Type 1, Type 2, and HHT-Juvenile polyposis overlap syndrome, each caused by mutations in different genes (ENG, ACVRL1, and SMAD4, respectively). These mutations disrupt the TGFβ (transforming growth factor-beta) pathway, which plays a crucial role in regulating angiogenesis, thus promoting the formation of abnormal blood vessels throughout the body.
Symptoms of HHT include recurrent epistaxis (nosebleeds) in about 90% of patients, gastrointestinal bleeding (25-30%), pulmonary AVMs (50%), cerebral AVMs (10%), and hepatic AVMs (40-70%). Pulmonary AVMs, in particular, can lead to dyspnea, hemoptysis, paradoxical emboli, and even cerebral abscesses.
The diagnosis of HHT is supported by the Curacao criteria, which include: recurrent spontaneous nosebleeds, mucocutaneous telangiectasias, visceral involvement, and a first-degree family history of the disease. A definitive diagnosis is made when at least three criteria are met, while two criteria suggest suspicion of the disease, and fewer than two criteria make HHT unlikely. Genetic testing can confirm the diagnosis and screen family members for mutations.
Treatment is multimodal, with the primary goal of managing bleeding episodes, correcting anemia, and addressing visceral AVMs. Treatments include nasal ointments, saline sprays, laser ablation, oral tranexamic acid, and embolization for larger or more symptomatic AVMs. Anti-VEGF agents such as bevacizumab may be used in severe cases but come with the risk of thromboembolism, hypertension, and peripheral neuropathy.
A 27-year-old female with known Hereditary Haemorrhagic Telangiectasia presented to the emergency department with symptoms of dizziness, breathlessness, desaturation, and epistaxis. Her initial workup revealed a low haemoglobin level (8.4 g/dL), and she was treated with 1 unit of PRBC transfusion. Serum ferritin levels were also low. The patient has a family history of HHT, with both her mother and sister diagnosed with the same condition.
Given her symptoms, including hypoxemia, embolization of pulmonary AVMs was planned. The procedure was successful, with the embolization of hypertrophied pulmonary arteries, dilated venous sacs, and early draining veins of the AVM. No significant filling was seen from the occluded branches.
Osler-Weber-Rendu Disease was first described by Henri Rendu in 1896, then by William Osler in 1902, and finally by Francis P. Weber in 1907, each reporting family cases of spontaneous epistaxis and cutaneous telangiectasias. Diagnosis of HHT is often based on the Curacao criteria, which require the presence of at least three features: recurrent epistaxis, mucocutaneous telangiectasias, visceral AVMs, and a family history of the disease. In cases where genetic testing is necessary, asymptomatic children of parents with HHT should be considered carriers unless the disease is excluded by genetic testing.
Pulmonary AVMs, commonly seen in HHT, typically present with round or oval areas of increased density on radiological imaging. These can be successfully treated with embolization, which is considered the gold standard of care. Surgery is reserved for patients who cannot undergo embolization or those with ruptured AVMs leading to haemothorax.
It is recommended that patients with pulmonary AVMs be screened every 3-5 years, particularly if they exhibit symptoms. Early intervention can significantly improve outcomes and quality of life for patients with this condition.
This case highlights the importance of timely diagnosis and treatment in managing the complications of Hereditary Haemorrhagic Telangiectasia, particularly in cases involving pulmonary AVMs. The use of embolization in this patient was successful, preventing further complications and improving her clinical status.
Ms. Sakthi Physician Assistant Kauvery Hospital Chennai
Mentor:
Dr. Anantha Subramanian Consultant Pulmonologist Kauvery Hospital, Chennai
