Insights on the Quality of Coagulation Testing

Transcription

1 Insights on the Quality of Coagulation Testing Piet Meijer ECAT Foundation The Netherlands

2 No conflicts of interest

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4 HAEMOSTATIC BALANCE BLEEDING

5 HAEMOSTATIC BALANCE THROMBOSIS

6 HAEMOSTATIC BALANCE Thrombosis Clotting Factors Inhibitors (AT, PC, PS) APC Resistance Bleeding Coagulation Factors Von Willebrand Factor Specific Inhibitors Lupus Anticoagulant D-Dimer

7 HAEMOSTATIC BALANCE Global Tests APTT PT Specific Tests Coagulation Factors Thrombophilia Markers Von Willebrand Factor Lupus Anticoagulant Specific Inhibitors D-Dimer

8 Global Tests Intrinsic Pathway Extrinsic Pathway XII APTT XI IX VII PT Intrinsic + Common VIII Common X V Pathway Extrinsic + Common II Fibrinogen Fibrin Clot

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10 Results in EQA survey Activator N Normal Plasma AC patient (INR ~2.5) Beijing Succeeder APTT I.L. HemosIL SynthAsil Siemens Actin FS Siemens Actin FSL Siemens Pathromtin SL Stago PTT Autom./STA APTT Stago Cephalin/Kaolin/CK Prest Stago Cephascreen

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13 Clinical cause for a prolonged APTT PROLONGED APTT Clotting Factor Deficiency Specific Inhibitor A-specific Inhibitor Treatment with anticoagulant

14 Ajzner et al. Clin Chem Lab Med 2015; 53(10):

15 Ajzner et al. Clin Chem Lab Med 2015; 53(10):

16 Global Tests Intrinsic Pathway Extrinsic Pathway APTT XII XI IX Vit. K dep. CF VII PT Intrinsic + Common VIII Common X V Pathway Extrinsic + Common II Fibrinogen Fibrin Clot

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18 Results in EQA survey Thromboplastin N Normal Plasma AC patient (INR ~2.5) I.L. HemosIL ReadiPlasTin I.L. HemosIL Recombiplastin 2G Siemens Innovin Siemens Thromborel S Stago (STA) Neoplastin CI Plus

19 International Normalised Ratio (INR) Classical laboratory parameter for monitoring anticoagulation therapy. Measurement of Prothrombin Time (PT) Harmonisation of test results to INR

20 Results in EQA survey Thromboplastin N Normal Plasma AC patient (INR ~2.5) I.L. HemosIL ReadiPlasTin I.L. HemosIL Recombiplastin 2G Siemens Innovin Siemens Thromborel S Stago (STA) Neoplastin CI Plus

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23 THROMBOSIS

24 Measurement uncertainty Thrombosis: D-Dimer An estimate of measurement uncertainty (MU) provides an interval of values within which the true value is believed to lie with a stated probability, and is therefore a quantitative indication of the reliability of a measurement. Clin Biochem Rev Vol 29 Suppl (i) 2008 S53 S60

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26 Assigned value: mg/l CV: % Measured value: 0.50 mg/l Relative MU: 10% Range:

27 Thrombosis: Lupus Anticoagulant Classification Lupus Anticoagulant samples Sample Negative Borderline Positive Neg. Cotrol 96% 2% 2% Weakly pos % 10 20% 45 70% Positive 5% 6% 89% Strongly pos. 0% < 0.5% > 99.5%

28 Lupus Anticoagulant Weak positive Relationship no. of testpanels? N - ± % 14% 72% % 20% 53% % 32% 22% > %

29 Screen Lupus Anticoagulant Normalisation of test results

30 BLEEDING

31 Bleeding: von Willebrand Factor Diagnose Von Willebrand Disease De Jong A, Eikenboom J. Developments in the diagnostic procedures for von Willebrand disease. J Thromb Haemost 2016;14:

32 Bleeding: von Willebrand Factor Classifications Type plasma Normal Type 1 Type 2 Type 3 No conclusion Nothing indicated Normal 91.5% 2.5% 6.0% 0.0% 10% 22% Type 1 1.1% 86.6% 12.3% 0.0% 14% 24% Type 2 0.6% 31.1% 68.3% 0.0% 18% 25% Type 2 1.1% 18.4% 80.4% 0.0% 13% 24%

33 Type % ratio Rco/Ag 44.7% ratio act/ag 18.1% ratio CB/Ag

34 Favaloro et al, Thrombosis Research (2018), in press

35 Bleeding: FVIII Van Moort et al, submitted

36 Bleeding: FVIII Van Moort et al, submitted

37 Take Home Messages External quality assessment (EQA) plays an important role in assuring the accuracy of measurement. From EQA results important insight could be obtained into the quality of coagulation testing. Participation in an EQA programme may benefit the laboratory to reveal problems in coagulation testing, get insight in their own performance and work on quality improvement in coagulation testing.