Prothrombin fragment 1+2 in urine as a marker on coagulation activity in patients with suspected pulmonary embolism

Role of Noninvasive Urinary Prothrombin Fragment 1 + 2 to Measure Blood Coagulation Indices and Dose of Acenocoumarol

PF1 + 2 plasma levels are a crucial indicator for assessing anticoagulant action in individuals receiving anticoagulant treatment. Urine also has PF1 + 2 levels due to its molecular size. Hence, the present study aims to measure urinary prothrombin fragment 1 + 2 (uPF1 + 2) in patients taking anticoagulants in order to divulge a noninvasive surrogate marker of PT-INR of blood coagulopathy. A total of 205 people participated in the study: 104 patients on acenocoumarol (AC) and 101 healthy controls (HC). Clinical parameters, including PT-INR, urinary creatinine, etc., were measured in all subjects. To evaluate uPF1 + 2 in samples, MALDI-TOF-MS, Western blot analysis, and ELISA tests were used. The MALDI-TOF-MS results showed the presence of uPF1 + 2 in both AC and HC urine samples. The Western blot, ELISA experiment, and unpaired t test results displayed that the patients with AC had significantly increased levels of uPF1 + 2 compared to HC. A regression study showed a strong positive relation between blood-based PT-INR and uPF1 + 2. ROC validation also revealed the clinical efficacy of uPF1 + 2. For the goal to monitor anticoagulant medication, the present study highlights PF1 + 2, which describes the overall hemostatic capacity and might be utilized in addition to or instead of PT-INR.

Thrombin Generation in Patients With Suspected Venous Thromboembolism

Increasing number of patients with clinically suspected venous thromboembolism is referred to radiological departments for definitive diagnosis. A simple assay to exclude the diagnosis and avoid radiological examinations is needed. We have reported correlations between D-dimer and prothrombin fragment 1 + 2 measured in plasma and urine. To further develop an analysis based on urine, more understanding of thrombin generation in these patients is needed. The aim of this study was to compare ex vivo thrombin generation with in vivo markers in plasma and urine in patients with and without venous thromboembolism. Urine and blood samples were collected from patients with suspected venous thromboembolism. Commercially available enzyme-linked immunosorbent assay (ELISA) kits were used to analyze the samples for in vivo thrombin generation. The ex vivo thrombogram parameters were measured by the calibrated automated thrombogram assay. Venous thromboembolism was verified with compression ultrasound of the lower extremity deep veins or with computer tomography of the pulmonary arteries. Venous thromboembolism was diagnosed in 117 of 591 patients, and they had significantly higher levels of urine and plasma prothromin fragment 1 + 2, D-dimer, lag time, time to peak, and endogenous thrombin potential when adjusted for covariates. The pattern of ex vivo and in vivo thrombin generation in patients with suspected venous thromboembolism was comparable when adjusted for covariates. Prothrombin fragment 1 + 2 in plasma and urine reflects thrombin generation ex vivo in the same manner. This indicates that urine may be an alternative substrate to quantify a procoagulant state.