The most common symptom of HHT is recurrent, heavy rhinorrhea; therefore, patients are most often seen in otolaryngology. The earliest case report was seen in 1864 and is an autosomal dominant disorder caused by a genetic mutation. 1. How do I know if I have HHT? There are 4 diagnostic criteria: ① rhinorrhea; ② capillary dilation of the skin mucosa; ③ arteriovenous malformation of the internal organs; ④ family history and mutation gene. If all 4 items are met, or 3 items are met, the diagnosis is clinically confirmed. If 2 items are met, it is suspicious. The first symptom in patients with HHT is recurrent spontaneous rhinorrhea, but it is usually asymptomatic in childhood. more than 50% of patients present with recurrent heavy rhinorrhea between 12 and 16 years of age, and more than 90% of patients have recurrent rhinorrhea by age 30. another symptom of HHT is islands or clusters of dilated capillary masses, mostly in the lips, tongue, and palms and fingers. Gastrointestinal bleeding occurs in 20% of patients. 5% of patients may develop severe brain, liver, and lung complications. If you are over 30 years old and do not have nasal bleeding and island-shaped dilated capillary masses, then you are very unlikely to have HHT. 2. What is the probability that HHT will be passed on to my children? There is a 50% chance that the affected parent will pass on the disease-causing gene to their child. Each child of a person with HHT has a 50% chance of developing the disease. This inheritance pattern is independent of the sex of the child and whether or not the child already has the disease. Even if you have four children with HHT, the risk of having a fifth child with the disease is still 50%. Also, siblings of the patient have a 50% risk of developing the disease. Genetic screening is required for patients with confirmed or suspected HHT. When the causative mutation is identified, asymptomatic children and sisters need to be screened for the mutation for early control to avoid serious complications of HHT. If the genetic screening results are negative, their family members do not need to be screened and the patient himself only needs to have regular check-ups of his internal organs. 3.I have been diagnosed with HHT, do I still need to have any more tests? If you have frequent nosebleeds or gastrointestinal bleeding, you need to have regular blood tests to see if you are anemic. Depending on the situation, give oral iron or blood transfusions if needed. About 20% of HHT patients have pulmonary arteriovenous malformations, which can have serious consequences if left untreated. A chest CT is recommended for every patient with HHT to screen for and rule out pulmonary arteriovenous malformations. If you have a family member with a pulmonary arteriovenous malformation, your own screening is even more important. Other complications of HHT require specialized testing. If necessary, your doctor will recommend a brain MRI and ultrasound of the liver, gallbladder, pancreas, spleen and kidneys. 4. What treatment is currently available? Anemia: Patients with recurrent bleeding are likely to have iron deficiency anemia due to excessive blood loss. Frequent oral iron preparations and/or blood transfusions are required. Oral iron preparations are used as much as possible when the disease permits, and blood transfusions are given for severe bleeding. Rhinorrhea: A variety of methods have received some efficacy in the treatment of rhinorrhea, but there is no complete cure. Cauterization of the diseased blood vessels can relieve the condition in the short term, but the long-term effect is poor. Estrogen therapy has some efficacy, but it is mainly used for female patients. It has significant side effects and cannot be used for male patients. Laser therapy: In the same way as cautery, this treatment also works on specific bleeding sites. Laser therapy is less effective for multiple capillary dilation in the nasal cavity or intestine; it is more effective when there are fewer bleeding sites. However, laser treatment is more expensive equipment. Skin grafting: When nasal bleeding is very severe and uncontrollable, skin grafting can be done in the nasal cavity. Pulmonary arteriovenous malformation: Most pulmonary arteriovenous malformations can be cured by radiological interventional embolization. A proximal vessel is cannulated through the upper or lower extremity, and a laminated balloon or steel ring is inserted through the cannula to block the abnormal vessel. Obstruction of the abnormal vessel reduces the complications of pulmonary arteriovenous malformation. Gastrointestinal bleeding: If the patient has frequent black stools or blood in the stool, gastroscopy is recommended to stop the bleeding under gastroscopy or take surgical procedures. 5.What does the patient need to pay attention to in general? Avoid blowing nose hard, use lubricant if nasal cavity is dry; anticoagulants are prohibited for patients with severe nasal bleeding or gastrointestinal bleeding. 6.Will the vascular malformation of internal organs gradually expand? The vascular malformation of the brain can remain unchanged, while the vascular malformation of the lungs will gradually expand. The malformed blood vessels in adolescents grow the fastest; in adults, they can be enlarged 1 times every 5~10 years. It is recommended that when pulmonary vascular malformations are found, regular checkups are performed so that timely surgery can be performed. 7.What is the current research progress? Four genes have been identified, HHT1, HHT2, HHT3, and HHT4. In addition, Smad4 is also associated with HHT and juvenile polyposis. We are working on HHT gene research in Chinese people, including screening for pathogenic genes in HHT patients, genetic screening for early diagnosis and early intervention in phenotypically “normal” HHT families, and screening for localization and cloning of new HHT pathogenic genes.