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Author Topic: D-Dimer ? what is it and what does it mean if test postive ?  (Read 6941 times)

neilep

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I have a friend who has tested positive for D-Dimer ?

I don't have a clue what this is (im just a sheep !)

Any chance of a plain english definition and what the implications are ?


Thanks

Sheepy
xxx

CliffordK

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Of course there is a Wikipedia page on D-Dimer.

So, it is a product of the breakdown of blood clots.  It is indicative of a few conditions including:
  • Deep Venous Thrombosis (DVT), or clots in the blood veins, typically in the legs
  • Pulmonary Embolism (PE). often a blood clot that has migrated from the leg (DVT) up through the right heart, and gets stuck in the lungs
  • Disseminated Intravascular Coagulation (DIC), a clotting malfunction that causes multiple mini-clots in the arterial/venous system.

RD

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Apparently itís only 50% specific for blood-clotting disease, ( i.e. only half the people with a positive result will actually have  developed blood clot(s) , the other half are false positive due to some other disease or old age ) ...

Quote
Various kits have a 93-95% sensitivity and about 50% specificity in the diagnosis of thrombotic disease.
   False positive readings can be due to various causes: liver disease, high rheumatoid factor, inflammation, malignancy, trauma, pregnancy, recent surgery as well as advanced age
https://en.wikipedia.org/wiki/D-dimer#Test_properties
« Last Edit: 04/11/2012 13:38:03 by RD »

neilep

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Thank ewe both CliffordK and RD for your kind responses. I will pass this info on to her.

circa late 20s, female.

CliffordK

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It says it can also occur with pregnancy.

According to Wikipedia, a negative result is better for excluding certain disease conditions, as a positive result may not be specific. 

I would assume there was a reason the test was conducted.

cheryl j

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The value of the test is that if it's negative, it almost completely rules out a blood clot so you can cross that diagnosis off the list. But if its positive it doesnt necessarily mean there is pulmonary embolism or other clot.

neilep

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Thank you again and also cheryl J.

After further inquiries she admits a history of blood clotting. You have all mentioned this. I'll consider this topic finalised now as it seems that her "treatment" is going through due process related to this.


RD

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Disseminated Intravascular Coagulation (DIC), a clotting malfunction that causes multiple mini-clots in the arterial/venous system.

Hopefully not DIC, given its backronym ...
Quote
... DIC is generally associated with an adverse outcome by most clinicians, and its acronym has been synonymous with "Death Is Coming."   
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC259170/
« Last Edit: 05/11/2012 06:11:22 by RD »

 

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