This article was guest written by Dr. Scott Olitsky, MD, MBA. Dr. Olitsky is the Chief Medical Officer for Cure HHT, the leading non-profit organization in the world working to advance awareness, research and treatments for Hereditary hemorrhagic telangiectasia (HHT).
Nosebleeds are not uncommon in the general population, and many people that experience nosebleeds do so with no obvious underlying cause for them. Nosebleeds can occur due to environmental reasons such as allergies or dry weather. Nosebleeds may occur in people who are on medications that alter coagulation which are used to treat a number of conditions such as atrial fibrillation, deep vein thrombosis, or to protect implanted stents after heart surgery. High blood pressure can lead to nosebleeds, as can less common medical conditions such as clotting disorders. For most people, a nosebleed is harmless and self-limited. However, there are times when recurrent nosebleeds can be linked to an underlying disorder that should not be overlooked.
Hereditary hemorrhagic telangiectasia (HHT) is a genetic disorder that causes recurrent nosebleeds in 90% of people with it. HHT is the second most common genetic bleeding disorder and is caused by several genetic mutations that lead to the development of abnormal blood vessels throughout the body. It is uncommon but not rare and is estimated to occur in 1 in 5000 people worldwide -- but only 10% of people with HHT have been diagnosed with it. The abnormal blood vessels that develop in HHT are fragile and tend to bleed easily. These abnormal blood vessels can occur on the skin, GI tract, and nose, leading to nosebleeds that range in severity from something that is little more than a nuisance to those that are life-threatening. They can also occur in the GI tract, where they can cause bleeding, as well as in the liver, lungs, and brain, where they can lead to heart failure, shortness of breath, and stroke. HHT is inherited in an autosomal dominant fashion, meaning that if you get just one abnormal gene from a parent, you will inherit the disease, and each parent has a 50% chance of giving it to a child. HHT does not skip generations.
Because the potential complications of HHT extend beyond nosebleeds, it is important to consider the possibility of the disease in people who experience frequent nosebleeds. How often do you need to have nosebleeds to warrant considering a diagnosis of HHT? A study done at the University of Utah showed that adults who have more than four nosebleeds a year are more likely to have HHT. However, it should be remembered that not everyone with more than this number of nosebleeds will have HHT and that some people with HHT never have one. Other clues in a person’s family history and physical examination can also be helpful in identifying those who may have HHT. If other family members also experience frequent nosebleeds, this would be important information to discuss with your doctor. Chronic anemia, GI bleeding, heart failure, and stroke can also be valuable clues if present in someone’s family.
The small abnormal blood vessels that occur on the skin are called telangiectasia. They appear as red dots on the skin that blanche when pressed. They may occur on any part of the body, but the most distinctive places to be seen in HHT include the lips and palms of the hands. When two or more telangiectasia are present in these locations, the likelihood of having HHT is much higher than when they are present in other regions of the skin.
Many of the more serious consequences of HHT can be avoided if a patient is known to have HHT and preventative screening is performed. That is why it is so important to consider HHT as a potential cause for recurrent nosebleeds. If one family member is identified, other family members must be screened or tested for the disease to prevent potentially catastrophic events. This often starts by discussing the possibility of HHT in someone with frequent nosebleeds.
In summary, HHT is an uncommon, but not rare, disease frequently characterized by recurrent nosebleeds. Having frequent nosebleeds, other family members with nosebleeds, a family history of anemia, GI bleeding and/or stroke along with possible red dots in certain areas of the skin, or any combination of these should raise a concern about the presence of HHT. They should be discussed with a physician that is knowledgeable about the disease.