Fredrik Wexels’ PhD theses shows that urine samples can offer valuable information in the assessment of patients with suspected venous thromboembolism.

MAIN RESULTS:

1. Higher levels of prothrombin fragment 1+2 in urine was associated with deep vein thrombosis, but not pulmonary embolism.
2. Urine prothrombin fragment 1+2 is not as accurate as plasma prothrombin fragment 1+2 or D-dimer for detecting venous thromboembolism.

3. Prothrombin fragment 1 + 2 in plasma and urine reflects thrombin generation ex vivo in the same manner.

THESIS DEFENCE:

Thesis: Markers of coagulation in urine and plasma in patients with suspected deep vein thrombosis and pulmonary embolism
Candidate: Fredrik Wexels
Time: March 15, 2018 at 13:15
Place: Domus Academica, University of Oslo: Gamle festsal
Link to university website (in Norwegian)

SUMMARY:

(1) Out of 534 patients with suspected deep vein thrombosis, the diagnosis was confirmed by imaging in 108. These patients had higher levels of prothrombin fragment 1+2 in urine compared to patients without deep vein thrombosis. The association was also confirmed in most patients with coexisting conditions, such as ongoing malignancy and pregnancy, but not in patients with infections and traumas.

(3) The same association could not be found in patients with pulmonary embolism. However, the subgroup of patients without comorbidities had higher levels of prothrombin fragment 1+2 in urine if they had confirmed pulmonary embolism. The diagnosis was confirmed in 44 of 197 included patients. 

(2) D-dimer in plasma had higher diagnostic accuracy than prothrombin fragment 1 + 2 in plasma and urine. There was a significant correlation between the three biomarkers, and all markers were increased in patients with imaging-confirmed venous thromboembolism.

(4) The pattern of thrombin generation analysed in plasma and urine was comparable in patients with suspected venous thromboembolism. Thus, urine samples could be an alternative to blood tests in the quantification of a procoagulant state.

REFERENCES:

(1) Wexels, F., Haslund, A., Dahl, O. E., Pripp, A. H., Gudmundsen, T. E., Laszlo, F., Seljeflot, I., Borris, L. C., & Lassen, M. R. (2013). Thrombin split products (prothrombin fragment 1+ 2) in urine in patients with suspected deep vein thrombosis admitted for radiological verification. Thrombosis research, 131(6), 560-563.

(2) Wexels, F., Dahl, O. E., Pripp, A. H., Seljeflot, I., Borris, L. C., Haslund, A., Gudmundsen, T. E., Lauritzen, T., & Lassen, M. R. (2014). Prothrombin fragment 1+ 2 in urine as a marker on coagulation activity in patients with suspected pulmonary embolism. Thrombosis research, 134(1), 68-71.

(3) Wexels, F., Seljeflot, I., Pripp, A. H., & Dahl, O. E. (2016). D-Dimer and prothrombin fragment 1+ 2 in urine and plasma in patients with clinically suspected venous thromboembolism. Blood Coagulation & Fibrinolysis, 27(4), 396-400.

(4) Wexels, F., Dahl, O. E., Pripp, A. H., & Seljeflot, I. (2017). Thrombin Generation in Patients With Suspected Venous Thromboembolism. Clinical and Applied Thrombosis/Hemostasis, 23(5), 416-421.