Question

NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE Ms. Gonzalez and the team look over the results from Tristan's bloodwork and discuss the possible outcomes. The extended PTT values, combined with the elevated platelets, make the team decide to call in the local hematology/ oncology specialist. Upon viewing the results the hematologist requests a factor VIII assay. Again you are curious as to what a factor VIII test is, and Dr. Johnson explains. Factor VII Assay This is a blood rest that measures the activity of factor VIII. Factor VIII or factor 8 is a large protein that is important to the clotting cascade. It accelerates the activation of factor X. Factor VIII is not an enzyme, but ir plays a large role in the activation of factor X. The factor VIII assay measures the percentage of factor VIII present in the blood. Results are represented as a percentage of factor VIII neded to from a clot. Normal levels range from 50-200%. When results are low, this test can be used to diagnose hemophilia A, Von Willebrand's disease, and presence of factor VIII inhibitor (an antibody). For hemophilia A, levels less than 19%% constitute severe hemophilia, 1-5% signifies moderate hemophilia, and values of 6-496 are diagnostic of mild hemophilia. When values are too high, this test can be used to diagnose/as a marker for diabetes, liver discase, inflammation, obesity, or pregnancy. Results from Tristan's test are listed below, Factor VII Assay Results-T. Hunter Measure Value Normal Factor VIII 0.27% 50-200% O Questions 6. What is factor VIII? Why would having a decreased/absent amount of factor VIII be problematic? 7. What can an abnormal factor VIII test result mean? Do any of these conditions overlap with the possible outcomes from the PTT test? Based on the combined results, what is the most likely diagnosis? "Black and Blue with Love" by Mell and Harris Page 6

Answer 1

6.what Is Factor VIII? Why would having a dacreased/ absent amount of factor VIII problematic?

Answer : Factor VIII is an essential blood clotting factor which helps in the clotting of blood.

It is also known as anti hemophilic factor.

In human factor VIII is encoded by the gene F8.

Defect in this gene result into a Haemophilia A recessive X- linked disorder.

People with high level of Factor VIII have a risk of Deep vein thrombosis and pulmonary embolism.

If you have abnormaly low level of Factor VIII it could caused by the following things

• inherited factor VIII deficiency.
• Disseminated intravascular Coagulation
• Von Willebrand's disease a disease that causes abnormal blood clotting.

Decreased/ absent amount leads to haemophilia condition.

Where due to deficiency of Factor VIII Blood will not clot or clot very slowly.

Factor VIII is involved in the last step of clotting process

Factor VIII , with factor IX, is involved in the last step of the clotting process

It involve in the formation of a "net" that closes a torn blood vessel. When an abnormal gene causes a child to be deficient in factor VIII, the result is a bleeding disorder known as hemophilia A.

7.what can an abnormal factor VIII test results mean, do any condition overlap with the possible out come from PTT test?

Based on combine result what is most likely diagnosed?

This test is done to check the level of factor VIII in the body.

As already told in the above question.

The abnormal level of factor VIII test means the patient may have deep vein thrombosis,or pulmonary embolism.

. PTT TEST. :.. This test is done to check the activity is factor VIII Blood protein.

PTT.. - partial thromboplastin time (PTT) and prothrombin time (PT) are usually the first step in hemophilia testing. These tests focus on clotting pathways.Even if you have hemophilia, the results of your PTT and PT tests may be normal, so the blood test for factor VIII is used to confirm the diagnosis.her you have hamophila A or other clotting disorders.

The abnormal factor test result mean you may have a hamophila A or other clotting disorders.

Test results are usually reported as a percentage of a Normal- result of 100%. Normal ranges for factor VIII levels are 50% to 150%.

If your factor VIII activity level is < 50%, you may have hemophilia A, but severity is depends on the percentage

If you have bleeding problems with normal to decreased level of factor VIII, you may have von Willebrand disease.

The combine result will tell you that you have any deficiency of any factor or of you have the problem the clotting of the blood.