Factor XI Activity Test

Factor XI is a protein which plays an important role in blood clotting. This test is used to measure the amount of factor XI in one’s blood. By not meeting with a sufficient amount of factor XI, the person may develop factor XI deficiency. This deficiency is a bleeding disorder also known as hemophilia C. Due to this deficiency the clotting reaction is blocked and the blood clot is not formed. This test is needed when a doctor may see symptoms of factor XI deficiency. A platelet count may also be done which is always done in case of any bleeding disorder.

No special preparation is needed for the test. However, there might be some complications which one will be facing before-hand, which may affect the outcome of the test. So, it is advisable that one may inform their doctors about all the medicines, herbal medicines, supplements such as vitamins and minerals they are taking. This information ensures that the doctor interprets the results of the test with full accuracy and avoid any chances of misdiagnosis.

After conduction of the test, it is analysed for the count of factor XI in the blood. From the reports, we may conclude: Low value – if the factor XI activity is less than 60%, then the causes can be one of them: Disseminated intravascular coagulation Congenital Deficiency Liver disease High value- if the factor XI activity exceeds the limit of 120% then there is a risk of a condition called venous thromboembolism. These tests are not the only alternative to conclude for the deficiency of Hemophilia C. Some other factors such as platelet count are also taken into consideration.

For this test to be done, patient’s blood sample is collected. This test is similar to the normal blood test. The blood is drawn from a vein in your arm, and the process is known as venipuncture. A needle is inserted into the vein, usually in the middle of the arm, to draw the blood into an attached tube. The blood is then immediately transferred into a container containing the clot activator and is sent to the laboratory for analysis.