International Journal of Hematology

ISSN 2997-1036

International Journal of Hematology | Vol. 12, No. 5, May 2021 | pp. 33–40
DOI: 10.46882/2021/IJH/000135

Original Article

Title: Screening for lupus anticoagulant using a simplified textrin time and kaolin clotting time mixing protocol in unprovoked deep vein thrombosis

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: Guidelines for diagnosing antiphospholipid syndrome require specific testing parameters that minimize false-positive results caused by circulating clotting factor variations. This prospective diagnostic study evaluated the performance of a combined screening protocol using the textrin time (TT) and the kaolin clotting time (KCT) mix to detect lupus anticoagulant in 70 adult patients presenting with acute, unprovoked lower limb deep vein thrombosis. Patient plasma underwent sequential 1:1 and 4:1 mixing loops with normal pooled plasma, followed by high-phospholipid corrections to calculate confirmatory ratios. Lupus anticoagulant presence was confirmed in 21.4% (15 of 70) of the thromboembolic cohort. The textrin-KCT dual mixing protocol achieved a diagnostic sensitivity of 91.4% and a specificity of 89.1% when cross-validated against international guidelines. Mixing indexes correlated positively with a clinical history of recurrent thrombotic events (r = 0.45, P < 0.05). Notably, the textrin-based step resisted interference from low-molecular-weight heparin due to its direct prothrombin activation pathway, providing a cost-effective and accurate thrombophilia risk-profiling asset for specialized clinical pathology laboratories.

Keywords: Lupus anticoagulant, textrin time, kaolin clotting time, mixing studies, deep vein thrombosis

Manuscript Timeline: Received: February 12, 2021; Revised: March 20, 2021; Accepted: April 05, 2021; Published: May 16, 2021