Armando Tripodi1, Hannah Cohen2,3, Katrien M J Devreese4. 1. Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center and Fondazione Luigi Villa, Milano, Italy. 2. Haemostasis Research Unit, Department of Haematology, University College London, London, UK. 3. Department of Haematology, University College London Hospitals NHS Foundation Trust, London, UK. 4. Coagulation Laboratory, Department of Diagnostic Sciences, Ghent University Hospital, Ghent, Belgium.
Abstract
BACKGROUND: The laboratory detection of lupus anticoagulants (LA) in anticoagulated patients represents a challenge and there is no consensus on the types of assays/procedures to be adopted. OBJECTIVES: This communication of the International Society on Thrombosis and Haemostasis (ISTH), Scientific and Standardization Committee (SSC) aims to give guidance on the procedures to be adopted. METHODS: Members of the ISTH-SSC on Lupus Anticoagulant/Antiphospholipid Antibodies reviewed the literature to search for evidence on the most appropriate assays/procedures to be adopted. RESULTS: Anticoagulants are able to interfere with the tests used for LA detection, giving rise to occasional false-positive or false-negative LA. Some commercial tests include in their composition heparin-neutralizers able to quench unfractionated or low molecular weight heparin up to 1.0 U/mL. LA tests are less affected by low molecular weight heparin, but caution is needed in the interpretation of results. Vitamin K antagonists (VKAs) may affect LA detection. Dilution of test plasma into pooled normal plasma is not a reliable solution as false-negative or false-positive LA may occur. Direct oral anticoagulants (DOACs) affect LA detection. Hence, it is not recommended to attempt LA detection in those patients. The use of DOAC adsorbents is a promising solution and should be further investigated on LA-positive and LA-negative patient populations. Taipan/Ecarin tests may be a solution for VKAs and anti-FXa DOACs, but independent evidence on their value and standardized kits is needed. CONCLUSIONS: LA detection during anticoagulation remains a challenge, especially for VKAs. DOAC removal by in vitro addition to plasma of appropriate absorbents is promising.
BACKGROUND: The laboratory detection of lupus anticoagulants (LA) in anticoagulated patients represents a challenge and there is no consensus on the types of assays/procedures to be adopted. OBJECTIVES: This communication of the International Society on Thrombosis and Haemostasis (ISTH), Scientific and Standardization Committee (SSC) aims to give guidance on the procedures to be adopted. METHODS: Members of the ISTH-SSC on Lupus Anticoagulant/Antiphospholipid Antibodies reviewed the literature to search for evidence on the most appropriate assays/procedures to be adopted. RESULTS: Anticoagulants are able to interfere with the tests used for LA detection, giving rise to occasional false-positive or false-negative LA. Some commercial tests include in their composition heparin-neutralizers able to quench unfractionated or low molecular weight heparin up to 1.0 U/mL. LA tests are less affected by low molecular weight heparin, but caution is needed in the interpretation of results. Vitamin K antagonists (VKAs) may affect LA detection. Dilution of test plasma into pooled normal plasma is not a reliable solution as false-negative or false-positive LA may occur. Direct oral anticoagulants (DOACs) affect LA detection. Hence, it is not recommended to attempt LA detection in those patients. The use of DOAC adsorbents is a promising solution and should be further investigated on LA-positive and LA-negative patient populations. Taipan/Ecarin tests may be a solution for VKAs and anti-FXaDOACs, but independent evidence on their value and standardized kits is needed. CONCLUSIONS: LA detection during anticoagulation remains a challenge, especially for VKAs. DOAC removal by in vitro addition to plasma of appropriate absorbents is promising.
Authors: Francesco Paciullo; Emanuele Valeriani; Angelo Porfidia; Marcello Di Nisio; Marco P Donadini; Rossella Marcucci; Domenico Prisco; Carlo Cagini; Paolo Gresele; Walter Ageno Journal: Blood Transfus Date: 2022-01-21 Impact factor: 5.752
Authors: Eva K Kempers; Virgil A S H Dalm; Marie Josee E van Rijn; Annemarie G M G J Mulders; Frank W G Leebeek; Moniek P M de Maat; A J Gerard Jansen Journal: Rheumatol Adv Pract Date: 2021-11-27
Authors: Hannah Cohen; Maria J Cuadrado; Doruk Erkan; Ali Duarte-Garcia; David A Isenberg; Jason S Knight; Thomas L Ortel; Anisur Rahman; Jane E Salmon; Maria G Tektonidou; David J Williams; Rohan Willis; Scott C Woller; Danieli Andrade Journal: Lupus Date: 2020-10 Impact factor: 2.911