A new diagnostic test has recently become available which is highly specific for plasma soluble
fibrin polymers, the
thrombus precursor
protein (
TpP) enzyme immunoassay. In order to evaluate the diagnostic accuracy of this test and that of a new rapid and automated test for the determination of D-dimers, the BC
D-dimer test, in patients with clinically suspected
deep vein thrombosis (DVT), 70 consecutive symptomatic patients underwent laboratory analysis with both tests and with the classic
enzyme-linked
immunosorbent assay (ELISA)
D-dimer test, followed by the execution of a compression ultrasound (
CUS) test of the affected limb. Patients with a positive
CUS test were considered to have DVT (20 of 70), whereas those with a serially negative test and an uneventful 3-month follow-up test were regarded as not having DVT (50 of 70). The sensitivity of the TpP test (45.0%) was significantly lower than that of both the BC
D-dimer test (80.0%; P = 0.02) and the classic ELISA test (90.0%; P = 0.002). The specificity of the TpP test (66.0%) did not differ from that of either
D-dimer test (60.0 and 64.0%, respectively). The negative predictive value of the TpP test (75.0%) was significantly lower than that of the classic ELISA
D-dimer test (94.1%; P = 0.02), which in turn did not differ from that of the BC
D-dimer test (88.2%). The positive predictive value was similarly low for each investigated test (34.6, 44.4, and 50.0%, respectively). In conclusion, the TpP test can neither be used to detect a DVT nor to exclude its development in patients with the clinical suspicion of this disease. By contrast, the BC
D-dimer might safely replace the classic ELISA test for excluding DVT in symptomatic patients.