Testing of Fibrinolysis

Question 1

Fibrinolytic System

Answer 1

Often the PT and APPT is normal in pts with fibrinolytic system abnormalities.
TCT may be abnormal

Question 2

Fibrin Degradation Products (FDPs)

Answer 2

Plasmin cleaves fibrin and yields FDPs.
Designated X, Y, D, E
*Detection of FDPs indicates increased fibrinolytic activity

Question 3

Increased FDPs seen in

Answer 3

DIC, deep vein thrombosis, pulmonary embolism, liver diseases, alcoholic cirrhosis, kidney disease, cardiac disease, postsurgical complications, carcinoma, myocardial infarction, eclampsia

Question 4

FDPs Assay Test based on

Answer 4

Antigen-Antibody reaction using latex agglutination immunoassay.
Results:
Negative: 2-10 ug/mL
Positive: >10 ug/mL

Question 5

D-Dimer Assay

Answer 5

More specific test for plasmin lysis of fibrin.
As fibrin digests clots, D-fragments are released from fibrin as D-Dimers (generated from factor XIIIa crosslinked fibrin)

Question 6

D-Dimer Assay is an excellent marker for

Answer 6

DIC (but can also be positive in liver disease and pulmonary embolism).
D-dimer test uses monoclonal antibodies against the D-dimer fragment.

Question 7

D-Dimer Assay (3 Test Methodologies)

Answer 7

Semiquantitative: assay that utilizes macroscopic latex agglutination.
Quantitative: technique using the ELISA format
Automated Procedure: latex agglutination