Christmas Disease (Hemophilia B)
What Is Christmas Disease?
Published: December 2017
Christmas Disease (Hemophilia B)
What Is Christmas Disease?
Christmas disease, also called hemophilia B or factor IX hemophilia, is a rare genetic disorder in which your blood doesn’t clot properly. If you have Christmas disease, your body produces little or no factor IX. This leads to prolonged or spontaneous bleeding. The less factor IX your body produces, the worse your symptoms are. Without treatment, Christmas disease can be fatal.
A person is born with Christmas disease, but it may not be diagnosed until later in life. It’s estimated that two-thirds of cases are inherited. The other cases are caused by spontaneous gene mutations that occur for unknown reasons during fetal development. The disease almost exclusively in males.
The disease is named for Stephen Christmas, who was the first person diagnosed with the condition in 1952.
How Is Christmas Disease Inherited?
The gene responsible for Christmas disease is carried on the X chromosome. Females have two X chromosomes and males have one X and one Y chromosome. If a male inherits the faulty gene on his X chromosome, he could develop Christmas disease. If a female inherits the faulty gene on one of her X chromosomes, she’ll be a carrier for Christmas disease and may pass the defective gene on to her children.
All daughters of a father who has the defective gene will be Christmas disease carriers. A father doesn’t pass the faulty gene on to his sons. A mother who carries the faulty gene has a 50 percent chance of having a son with Christmas disease and a 50 percent chance of having a daughter who’s a carrier of the disease.
Females are usually only carriers because they have two X chromosomes. If they inherit the faulty gene on one X chromosome, the other X chromosome produces sufficient factor IX for blood clotting. However, female carriers may produce less factor IX than women who aren’t carriers, which can result in mild abnormal bleeding after injuries or surgical procedures. A female can inherit Christmas disease if both of her parents pass the faulty gene on to her, although it’s rare for a female to have two parents with the faulty gene.
Genetic Testing for Christmas Disease
If you’re a woman with a family history of Christmas disease, you can have genetic testing to see if you carry the faulty gene. Genetic testing is a very accurate way to detect the faulty gene.
What Are the Symptoms of Christmas Disease?
Severe cases of Christmas disease are usually diagnosed in babies younger than 1 year old. Mild cases may not be diagnosed until a child reaches their toddler years or sometimes even later. In all cases, diagnosis usually happens after abnormal bleeding from an injury or surgery.
Events that may lead your doctor to suspect Christmas disease include:
prolonged bleeding, such as can occur during circumcision, after surgical procedures or tooth extractions, or from cuts or other wounds
unexplained, excessive bruising or prolonged nosebleeds
unexplained blood in the urine or feces caused by internal bleeding in the gastrointestinal or urinary tract
internal bleeding that pools in the joints, which causes pain and swelling
Severe cases of Christmas disease may cause unexplained bleeding in the skull after childbirth and spontaneous bleeding.
Diagnosing Christmas Disease
If you or your child shows symptoms of Christmas disease, your doctor may order blood tests to confirm the diagnosis, including:
a factor IX test to determine how much of the clotting factor is present in your blood
an activated partial thromboplastin time test to detect how fast your blood clots
a prothrombin time test, which is another test to detect how quickly your blood clots
a fibrinogen test to determine your body’s ability to form a clot
How Is Christmas Disease Treated?
There’s no cure for Christmas disease, but there are treatments for the condition. Regular treatment is essential for managing the symptoms of Christmas disease.
Factor IX Injections
Christmas disease can be treated with factor IX injections to prevent or stop bleeding. The factor IX can be derived from donated human blood or made in a laboratory. Artificial factor IX is called recombinant factor IX and is generally recommended over blood-derived factor because it’s safer. Blood-derived factor IX may contain dangerous pathogens, such as hepatitis or HIV. However, the risks of contracting HIV and hepatitis from factor IX treatment is lower than ever due to improved blood-screening practices.
If you have a mild form of Christmas disease, your doctor may give you a product called desmopressin acetate to apply to small wounds to stop the bleeding. Larger wounds and internal bleeding require medical treatment from your doctor.
If you have a severe form of Christmas disease, you may need preventive blood transfusions to avoid or reduce prolonged and heavy bleeding, which is known as prophylaxis. These are especially important in children. If you receive blood-derived factor or blood transfusions, you should be vaccinated for hepatitis B.
There’s a slight chance that you could die from excessive blood loss, experience bleeding in the brain, or have long-term joint problems from internal bleeding. In rare cases, the treatment for Christmas disease may result in an abnormal thrombosis, or clot formation.
Further complications of Christmas disease may be prevented through annual checkups as and regular blood testing for infections. You should also avoid aspirin and other medications that can interfere with blood platelet function.
With treatment, most people with Christmas disease are likely to lead normal lives. Since there’s no cure for the disease, it’s important to make sure you avoid situations in which excess bleeding could occur. You also can receive blood-clotting therapy before any surgery or after any injury.
Living with Christmas disease can be stressful for those who have it and their families, especially when accidents or injuries that could lead to excessive bleeding occur. Talk to your doctor about ways you can prevent bleeding and ask for tips about how to manage your condition if an injury occurs.