ISSN 2997-1036
International Journal of Hematology | Vol. 14, No. 1, January 2023 | pp. 1–8
DOI: 10.46882/2023/IJH/000155
Original Article
Title: Screening for lupus anticoagulant using a simplified textrin time and thromboplastin time mixing protocol in unprovoked venous thromboembolism
Names of Authors: Y. Z. Ibrahim¹, A. B. Okafor², C. D. Danjuma³
Authors’ Affiliations: ¹Department of Haematology, Usmanu Danfodiyo University Teaching Hospital, Sokoto, Nigeria; ²Department of Pathology, University of Ibadan, Ibadan, Nigeria; ³Department of Haematology, University of Maiduguri, Maiduguri, Nigeria
Abstract: Diagnosing antiphospholipid syndrome requires robust laboratory testing parameters that can successfully isolate circulating inhibitors from baseline clotting factor variations. This prospective diagnostic study evaluated the performance of a combined screening protocol using the textrin time (TT) and the standard activated partial thromboplastin time (aPTT) mix loop to detect lupus anticoagulant in 70 adult patients presenting with unprovoked lower limb venous thrombosis. Patient matrices underwent sequential 1:1 mixing steps with normal pooled plasma, followed by high-phospholipid corrections to calculate confirmatory ratios. Lupus anticoagulant presence was confirmed in 22.8% (16 of 70) of the thromboembolic cohort. The textrin-aPTT mixing protocol achieved a diagnostic sensitivity of 92.8% and a specificity of 90.1% when cross-validated against international guidelines. Mixing indexes correlated positively with a history of recurrent thrombotic episodes (r = 0.48, P < 0.05). Notably, the textrin step resisted interference from low-molecular-weight heparin due to its specific prothrombin-activating mechanism, providing a highly reliable and cost-effective screening asset for regional laboratories handling patients on active anticoagulation.
Keywords: Lupus anticoagulant, textrin time, activated partial thromboplastin time, mixing studies, venous thromboembolism
Manuscript Timeline: Received: October 14, 2022; Revised: November 20, 2022; Accepted: December 08, 2022; Published: January 14, 2023