No, HHT Does Not Cause Bone Cysts
Hereditary hemorrhagic telangiectasia (HHT) is not associated with bone cysts and should not be considered as a cause of this finding. HHT is a vascular disorder that exclusively affects blood vessels, not bone tissue.
What HHT Actually Affects
HHT is characterized by abnormal blood vessel formation (vascular malformations) in specific locations 1, 2:
- Mucocutaneous sites: Skin and mucous membranes (nose, gastrointestinal tract)
- Visceral organs:
- Lungs (pulmonary arteriovenous malformations)
- Liver (hepatic vascular malformations)
- Brain and spinal cord (cerebral arteriovenous malformations)
The disease results from mutations in genes encoding proteins of the BMP signaling pathway (primarily ENG and ACVRL1), which leads to dysregulated angiogenesis—the formation of abnormal blood vessels 2.
Clinical Manifestations of HHT
The Second International HHT Guidelines 1 identify the following priority manifestations:
- Epistaxis (recurrent nosebleeds) - occurs in >90% of adults
- Gastrointestinal bleeding from telangiectasias
- Anemia and iron deficiency from chronic bleeding
- Complications from arteriovenous malformations in lungs, liver, and brain
- Telangiectasias on skin and mucous membranes
Notably absent from all comprehensive HHT guidelines and recent literature is any mention of bone involvement or cyst formation 1, 3, 2.
Important Caveat
If a patient presents with both bone cysts and features suggestive of HHT, these are likely two separate conditions requiring independent evaluation. The bone cysts warrant their own diagnostic workup based on their imaging characteristics, location, and clinical context—completely separate from any HHT evaluation.