Hemophilia C

What is hemophilia C?

Hemophilia C (also known as Factor XI Deficiency or Rosenthal syndrome) is a rare form of hemophilia. Hemophilia is a blood disorder that happens when your blood doesn’t clot so your bleeding slows down or stops. People who have hemophilia C are missing a specific blood protein, or clotting factors, that helps make blood clots. Hemophilia C causes less serious symptoms than other hemophilia types. But people who have hemophilia C may still bleed more than usual if they have surgery or certain dental treatments. Healthcare providers treat hemophilia C by giving people fresh frozen plasma from donated blood. The donated plasma helps blood to clot.

Is hemophilia C a common condition?

No, it’s very rare. Hemophilia C affects 1 in 100,000 men and women (or people assigned male/female at birth) in the United States. In comparison, hemophilia A affects about 12 in 100,000 men and hemophilia B affects about 4 in 100,000 men. Researchers aren’t sure how many women may have hemophilia A or B.

What’s the difference among hemophilia A, B and C?

All three hemophilia types are inherited blood disorders that happen when a genetic mutation affects the blood clotting process. Here are some of the differences among the three hemophilia types:

• Hemophilia A and B happen when someone inherits a mutated gene from one of their biological parents. In hemophilia C, people may inherit abnormal genes from both biological parents.
• Unlike people with hemophilia A or B, people with hemophilia C don’t have bleeding issues that affect their joints or muscles.
• In general, people with hemophilia A or B have symptoms that align with certain blood clotting proteins or factors. For example, someone who has severe hemophilia A symptoms also has very low factor levels. People with hemophilia C may have very mild symptoms even though they have very low factor levels.
• Hemophilia A and B affect all races and ethnic groups. People of Ashkenazi Jewish descent are more likely to have hemophilia C.
• Hemophilia A and B are more common in men than women. Hemophilia C affects both sexes equally.

What are hemophilia C symptoms?

People with hemophilia C may develop uncontrollable or prolonged bleeding after major surgery, a very serious injury or giving birth. But they don’t have spontaneous bleeding, which happens when people bleed for no apparent reason. Most often, people with hemophilia C have unusual bleeding after dental surgery, having a tooth removed or surgery to remove their tonsils. Other symptoms include:

• Nosebleeds.
• Bruising easily.
• Blood in pee.
• Excessive bleeding after circumcision.
• Painful, swollen bruises after surgery.
• Unusually heavy or long-lasting periods.

What causes hemophilia C?

Hemophilia C is an inherited blood disorder. It happens when you don’t have one of the 13 clotting factors, or blood proteins, that help slow or stop blood flow. In hemophilia C, you don’t have the clotting factor or blood protein XI, sometimes called factor 11, because you didn’t inherit the F11 gene.

Normally, the F11 gene carries instructions on how to create factor XI. Hemophilia C happens when that gene mutates and becomes an abnormal gene. This abnormal gene may not make enough factor XI or may not make factor XI.

Males and females inherit hemophilia C when both biological parents pass on the mutated gene. People who inherit a normal F11 gene and an abnormal gene will carry hemophilia C, but they won’t have symptoms. Here’s information on what may happen if people with the abnormal gene have children:

• There’s a 25% chance that children born to parents who have the F11 gene will have hemophilia C.
• There’s a 50% chance children born to those parents will carry the gene but won’t have the condition.
• There’s a 25% chance children born to those parents will inherit a normal F11 gene.

How do healthcare providers diagnose hemophilia C?

Healthcare providers diagnose hemophilia C by doing a physical examination, evaluating symptoms like bloody noses or bleeding after dental treatment, and asking about any biological family history of hemophilia or blood disorders.

What tests do healthcare providers use to diagnose hemophilia C?

There are two main tests that your healthcare provider will use to confirm your diagnosis:

• Activated partial thromboplastin time test: This hemophilia screening test tells your healthcare provider how long it takes your blood to clot.
• Clotting factor test: This blood test shows the hemophilia type and severity.

In some cases, your healthcare provider may also request other tests, including:

• Complete blood count: Healthcare providers use this test to measure and study blood cells.
• Prothrombin time (PT) test: Healthcare providers use this test to see how quickly your blood clots.
• Fibrinogen test: This blood test measures the amount of blood protein fibrinogen, which helps with clotting.

Hemophilia C is sometimes difficult to diagnose because blood tests results, particularly clotting factor test results, don’t align with people’s symptoms. For example, a clotting factor test may show you have a very low level of clotting factor, but you don’t have any symptoms. Conversely, you can have hemophilia C symptoms even though your clotting factor level is normal.

How do healthcare providers treat hemophilia C?

People with hemophilia C may not need treatment unless they’re going to have surgery or other procedures. When they do, healthcare providers use a combination of fresh frozen plasma from donated blood and medication that keeps replacement clotting factors from breaking down. They may prescribe birth control pills for women who have unusually heavy or long-lasting periods.

Can I prevent hemophilia C?

No, you can’t prevent hemophilia C because it’s an inherited blood disorder.

What can I expect if I have hemophilia C?

Most people who have hemophilia C have mild symptoms that don’t cause serious medical

A note from Cleveland Clinic

Hemophilia C is very rare and rarely causes serious medical issues. Most people with hemophilia C don’t have symptoms until they’re adults, and those symptoms are usually quite mild. That said, you may develop bleeding problems after surgery or dental treatment. If you have hemophilia C, ask your healthcare provider about precautions you should take.