Urine test can detect venous thromboembolism

A simple urine test has been developed that can indicate the presence of venous thromboembolism (VTE). This test evaluates the levels of fibrinopeptide B (FPB), a small peptide that is released when a thrombus forms and which excreted via urine.

The researchers had performed a pilot trial that suggested that urine FPB levels could be used as a screening tool for VTE in patients at risk for clots. Based on these findings, the current study was designed.

The advantage of a urine FPB test is that no blood needs to be drawn. Moreover, it can provide more accurate results than the D-dimer test. D-dimer is present in the blood only after a clot is degraded. FPB reflects ongoing clot activity, thus the FPB test has the potential for greater specificity.

The researchers used stored urine samples taken from 344 patients who participated in the Pulmonary Embolism Diagnosis Study (PEDS), a multicenter study of 1417 patients considered likely to have an acute pulmonary embolism. For all urine samples, the researchers measured the FPB concentration and evaluated the sensitivity and specificity of the test at various cut-off points in relation to its ability to predict the presence of VTE.
At concentrations of 2.5 ng/ml, urine FPB demonstrated sensitivity comparable to previously published values for plasma latex and whole blood D-dimer levels, but with greater specificity.

The authors conclude that ‘these results indicate that urine FPB tests may be a useful complement to current biomarkers such as D-dimer to measure for the presence and activity of venous thromboembolism.

The patent for the urine fibrinopeptide B test is held by the University of California Board of Regents. The researchers plan on developing a urine dipstick test for FPB that could be quickly and widely applied. The results of the study were presented at the American Thoracic Society's 2014 International Conference.
 EurekAlert
Fernandes TM, De Santis D, Chiles PG et al. Urine Fibrinopeptide B As A Screening Test For Acute Pulmonary Embolism. American Thoracic Society's 2014 International Conference Abstract 53841