Hereditary haemorrhagic telangiectasia (HHT), also known as Osler–Weber–Rendu syndrome, is a rare autosomal dominant genetic disorder that leads to abnormal blood vessel formation:
Telangiectasia: in the skin and mucous membranes (red or purple spots under the skin)
Arteriovenous malformations (AVMs): in organs such as the lungs, liver and brain
The most common problem is nosebleeds (epistaxis), acute GI blood loss, and chronic GI blood loss, leading to IDA.
Management may include iron supplementation, blood transfusion, laser treatment for telangiectasia and embolisation or surgery for AVMs.