An older related test was the test for "split products". The d-dimer test is helpful in working up blood clotting (thrombotic) disorders so as to detect or rule out evidence of thrombolysis (clot dissolving activity). It is an especially helpful test, by rapid methods, in excluding signs and symptoms being due to venous pulmonary thrombo-emboli (VTE or PTE or PE). [our recent newsletter]

Ours is a quantitative assay available 24/7/365 STAT @ Lexington Medical Center. Our normal-range study indicated "normal" as less than 0.48 ug/ml (literature indicating less than 0.5). Normal levels are 95-99% predictive in excluding (ruling out) the presence of PE ("negative is negative" for PE or any other clotting/thrombotic disorder..."positive" is "indeterminate" in that it only nonspecifically indicates that the blood thrombolytic system is revved up...not necessarily revved up against PE).

Increased levels are reflective of any of the vast number of possible diseases/causes having at least a component of thrombolysis. BUT, one of the higher levels we've seen was a FALSE POSITIVE on an associate with elevated rheumatoid factor...a well-known interference in immunological-type tests.

In conjunction with the Wells Clinical Decision Score [on line calculator], the test can screen out those who almost certainly DO NOT have VTE.

(posted 29 January 2003; update 25 November 2010)