Abstract Number: PB0600
Meeting: ISTH 2020 Congress
Background: Fibrin degradation products, D-Dimer and X-oligomers, are biomarkers for activation of coagulation. A normal D-Dimer result (< 0.5 µg fibrinogen equivalent unit [FEU]/mL), in combination with low/intermediate clinical probability assessment, may identify patients at low risk of proximal DVT and PE.
Aims: Evaluate the clinical performance of the new Tina-quant® D-Dimer Gen 2 assay (cobas t 711 analyser; Roche Diagnostics) for identifying patients with low/intermediate pre-test probability (PTP), by Wells score, who are at low risk of proximal DVT/PE.
Methods: Prospective, observational, multi-centre study using samples collected from six European hospital emergency departments and specialist referral centres, or purchased from commercial vendors. Eligible patients: aged ≥ 18 years; presenting with DVT/PE symptoms; low/intermediate PTP for DVT/PE by Wells score. Main exclusion criteria: DVT/PE symptoms for > 7 days; previous DVT and/or PE. Written informed consent was obtained pre-enrolment. DVT and/or PE were diagnosed by physicians via local imaging protocols, and patients followed-up for ≥ 90 days. Patients were assigned to DVT and PE (with/without concomitant DVT) cohorts. Citrated plasma samples were analysed at a central site using the Tina-quant D-Dimer Gen 2 assay, considering a standard 0.5 µg FEU/mL cut-point; negative predictive value (NPV), positive predictive value (PPV), sensitivity and specificity were determined.
Results: The study population comprised 2516 evaluable patients, 1741 in the DVT cohort and 775 in the PE cohort. Overall NPV and sensitivity (95% CI) for ruling out proximal DVT and/or PE were high: 100.0% (99.7-100.0) and 99.3% (96.0-100.0), respectively. Overall PPV and specificity (95% CI) were 20.0% (17.1-23.2) and 77.0% (75.3-78.7), respectively. Table 1 presents results by cohort.
Conclusions: In our study population, a normal result (< 0.5 µg FEU/mL) on the Tina-quant D-Dimer Gen 2 assay (cobas t 711 analyser) excluded proximal DVT and PE with high sensitivity in patients with low/intermediate clinical probability.
| Parameter, % (95% CI) | DVT cohort | PE cohort | ||||
| All (n=1741) | Low PTP (n=140) | Moderate PTP (n=1601) | All (n=775) | Low PTP (n=230) | Moderate PTP (n=545) | |
| NPV | 100.0 (99.7-100.0) | 100.0 (97.0-100.0) | 100.0 (99.7-100.0) | 99.8 (98.8-100.0) | 100.0 (98.0-100.0) | 99.7 (98.1-100.0) |
| PPV | 15.7 (12.2-19.8) | 0.0 (0.0-17.7) | 16.5 (12.8-20.8) | 25.3 (20.6-30.6) | 9.6 (3.2-21.0) | 28.5 (23.1-34.5) |
| Sensitivity | 100.0 (93.9-100.0) | 0.0 (N/A) | 100.0 (93.9-100.0) | 98.7 (93.2-100.0) | 100.0 (47.8-100.0) | 98.7 (92.7-100.0) |
| Specificity | 81.2 (79.2-83.0) | 86.4 (79.6-91.6) | 80.7 (78.6-82.6) | 67.0 (63.3-70.4) | 79.1 (73.2-84.2) | 61.2 (56.6-65.6) |
[Table 1. Clinical performance of the Tina-quant D-Dimer Gen 2 assay by cohort and PTP classification]
To cite this abstract in AMA style:
Bertsch T, Blaschke S, Body R, Davidson S, Guo G, Horner D, Sun Y, Turnes L, Sonner U, Hoffmann M. Clinical Performance of the Tina-Quant D-Dimer Gen 2 Assay on the Cobas t 711 Analyser for Evaluation of Patients with Suspected Deep Vein Thrombosis (DVT) and/or Pulmonary Embolism (PE) [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/clinical-performance-of-the-tina-quant-d-dimer-gen-2-assay-on-the-cobas-t-711-analyser-for-evaluation-of-patients-with-suspected-deep-vein-thrombosis-dvt-and-or-pulmonary-embolism-pe/. Accessed October 2, 2023.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/clinical-performance-of-the-tina-quant-d-dimer-gen-2-assay-on-the-cobas-t-711-analyser-for-evaluation-of-patients-with-suspected-deep-vein-thrombosis-dvt-and-or-pulmonary-embolism-pe/