Clauss Method and D-dimer Test Quiz

What is the principle of the Clauss method for measuring fibrinogen?

• Measuring fibrin polymerization time

• Determining platelet aggregation rate

• Fibrinogen concentration based on thrombin time of diluted plasma

• Detecting antibody response to fibrinogen

The Clauss method requires pre-warming thrombin reagent at:

• 25°C

• 37°C

• 40°C

• 50°C

In the D-dimer test, what indicates a positive result?

• Clear plasma

• Agglutination of latex particles

• Fibrin thread formation

• Red blood cell lysis

The presence of D-dimers primarily indicates:

• Fibrinolysis

• Platelet aggregation

• Prothrombin activation

• White blood cell activation

The reference plasma in the Clauss method is diluted with:

• Distilled water

• Imidazole buffer

• Sodium chloride

• Normal saline

In the D-dimer test, a sample with no agglutination at 1:8 dilution likely has a D-dimer level of:

• Less than 500 ng/mL

• 500–1000 ng/mL

In Mixing Studies, what does a correction in prolonged PT or APTT indicate?

• Presence of a clotting factor inhibitor

• Clotting factor deficiency

• High platelet count

• Increased D-dimer level

The Anti-Xa assay is primarily used to monitor: ________

• Warfarin therapy

• Low molecular weight heparin

• Aspirin therapy

• Vitamin K levels.

What is the main goal of Mixing Studies?

• Detecting platelet count

• Confirming the presence of inhibitors

• Measuring D-dimer levels

• Diagnosing liver disease.

The therapeutic range of anti-Xa for unfractionated heparin is:

• 0.1–0.3 U/mL

• 0.3–0.7 U/mL

• 0.8–1.2 U/mL

• 1.0–1.5 U/mL