What Is Factor XI in hemophilia?

Factor XI (FXI) deficiency, also called hemophilia C, plasma thromboplastin antecedent deficiency and Rosenthal syndrome, was first recognized in 1953 in patients who experienced severe bleeding after dental extractions. Its incidence is estimated at 1 in 100,000 in the general population.

Why is hemophilia B called Christmas?

Hemophilia B is also known as Christmas disease. It is named after the first person to be diagnosed with the disorder in 1952, Stephen Christmas. As the second most common type of hemophilia, it occurs in about 1 in 25,000 male births and affects about 4,000 individuals in the United States.

What is factor IX level?

Normal plasma levels of factor IX are 50 to 150 units/dl. Patients with levels less than 1 unit/dl have severe disease, those with levels of 1 to 5 units/dl moderate disease, and those with levels greater than 5 units/dl mild disease. The half-life of factor IX is approximately 18 to 24 hours.

What is the result of deficiency of Factor IX?

Hemophilia B is the result of a deficiency of clotting factor IX. The severity of symptoms can vary, and the severe forms become apparent early on. Bleeding is the main symptom of the disease and sometimes, though not always, occurs if an infant is circumcised.

What is normal factor XI levels?

Results are given in units per deciliter (U/dL). The normal range for factor XI activity levels is 65 to 130 U/dL, or 65% to 130%. If your results are lower than normal, it means you may have factor XI deficiency. This condition is quite rare and happens most often among people with Ashkenazi Jewish background.

What is Factor 9 blood test?

The factor IX assay is a blood test that measures the activity of factor IX. This is one of the proteins in the body that helps the blood clot.

How is Factor 9 activated?

Coagulation factor IX is made in the liver. This protein circulates in the bloodstream in an inactive form until an injury that damages blood vessels occurs. In response to injury, coagulation factor IX is activated by another coagulation factor called factor XIa.

How common is factor XI deficiency?

The incidence of factor XI deficiency is higher in individuals of Ashkenazi Jewish descent where it is estimated to affect 8% of the population. The severe form of the disorder is estimated to affect approximately 1 in 1,000,000 people in the general population.

What is the current treatment for hemophilia?

The current, most-used treatment for hemophilia A is factor replacement therapy. This is done by infusing (giving medication into a vein) a FVIII product into the affected person.

What are the effects of hemophilia?

Hemophilia mainly affects joints and muscles causing spontaneous bleeding after an injury or cut. Person with hemophilia can experience extended bleeding along with bruising leading to inflamed joints. Digestive problems and abdominal bleeding are the common concerns in people with hemophilia.

How do you treat hemophilia?

Treatment of Hemophilia. The best way to treat hemophilia is to replace the missing blood clotting factor so that the blood can clot properly. This is typically done by injecting treatment products, called clotting factor concentrates, into a person’s vein.

What is factor IX activity?

The factor IX assay is a blood test that measures the activity of factor IX. This is one of the proteins in the body that helps the blood clot.