Abstract - 2018 - Research and Practice in Thrombosis and Haemostasis

Everything You Need To Know About Hemophilia C (Factor XI Deficiency)

Hemophilia C is a rare, inherited blood disorder due to a deficiency of blood clotting protein Factor XI. It's less severe than hemophilia A and B and is inherited differently. Still, it can cause excessive bleeding.

Hemophilia is a rare genetic disorder that prevents your blood from clotting properly. This can lead to heavy bleeding, which can be life threatening.

In healthy people, blood clots when there is damage to a blood vessel. Blood clotting is a complicated process that requires different protein molecules called clotting (or coagulation) factors. There are 13 clotting factors, numbered using Roman numerals from I to XIII.

Hemophilia occurs when there is a mutation (change) in one of the genes that make your clotting factors. There are several types of hemophilia, which doctors classify according to which clotting factor is affected. Hemophilia C results from a mutation in factor XI. It's also called factor XI deficiency or Rosenthal syndrome.

In this article, we'll talk about hemophilia C — its causes, symptoms, diagnosis, treatment, and outlook for people with this condition.

Hemophilia C is an autosomal disease. This means that the F11 gene responsible for this condition is not located in one of the sex chromosomes (X or Y). This is different from hemophilia A and B, both of which are the result of genes in the X chromosome.

Hemophilia C is also a recessive disease. This means you need two copies of the mutated F11 gene (one from each parent) to have symptoms. People with one copy are called carriers and can pass this condition to their children.

In rare cases, some people experience symptoms of hemophilia C with only one copy of the mutated gene.

How common is hemophilia C?

Hemophilia C is very rare. Experts estimate it affects only 1 out of 100,000 people in the world.

But some people may have a higher risk of developing this condition. For example, experts estimate that up to 8% of Ashkenazi Jews living in Israel have this disorder.

A doctor may suspect hemophilia based on your symptoms or if you're related to someone with the condition.

To diagnose hemophilia C, a doctor called a hematologist will likely order a series of blood tests to look at your blood, its coagulation (clotting) properties, and the levels of clotting factors. These tests include:

They may also order a genetic test to confirm the diagnosis and identify the specific genetic mutation responsible for the disorder.

After confirming a diagnosis, your doctor may recommend genetic counseling, especially if you're planning to have children.

Hemophilia C is a rare bleeding disorder caused by a mutation in the F11 gene that makes clotting factor XI. It's mostly an autosomal recessive genetic disorder, meaning you need two copies of the mutated gene to have the condition. Still, there are reported cases where people have hemophilia C with only one mutated gene.

Hemophilia C is different from other types of hemophilia. It's a relatively mild condition that affects all genders equally. Many people with this condition may not know they are affected until they have a procedure, most often dental surgery.

Most people with hemophilia C don't need treatment unless they have severe bleeding. Healthcare professionals can control the bleeding with fresh frozen plasma and certain medications.

Although hemophilia C is potentially life threatening, most people enjoy long and healthy lives. Still, it's important to avoid activities that can cause injuries.

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