Test 3: D-Dimer Test (Latex Assay)

Question 1

the major clot lysing enzyme
can cleave both fibrinogen and fibrin to yield various degradation products.

Answer 1

Plasmin

Question 2

When plasmin lyses fibrinogen, it produces…

Answer 2

Fibrinogen Degradation Products (FDPs, also known as Fibrin Split Products, or FSPs: fragments X, Y, D & E).

Question 3

A pos. D-Dimer test means…

Answer 3

fibrin lysis

Question 4

a neg. D-Dimer rules out…

Answer 4

DIC or any other type of thromboembolism

Question 5

the best use of D-Dimer is as a ___________ predictive index

Answer 5

negative

Question 6

FDPs/FSPs may be assayed for by qualitative/semi-quantitative _____________ tests

Answer 6

latex agglutination

Question 7

D-Dimers may be assayed for by similar latex tests, as well as by automated ______ methodology, or by the reference standard method of immunoturbidimetry.

Answer 7

ELISA

Question 8

Specimen Requirements for D-dimer test

Answer 8

Fresh plasma collected in citrate, EDTA or heparin.
Procedure:

Question 9

Positive D-dimer test…

Answer 9

> 0.25 ug/mL

Question 10

negative D-dimer test…

Answer 10

< 0.25 ug/mL

Question 11

What can cause a positive D-dimer result?

Answer 11

DVTs, PEs, and DIC

Question 12

What can cause a false positive?

Answer 12

rheumatoid arthritis