ISSN 2997-1036
International Journal of Hematology | Vol. 9, No. 9, September 2018 | pp. 65–72
DOI: 10.46882/2018/IJH/000105
Original Article
Title: Screening for lupus anticoagulant using an integrated dRVVT and dilute Russell's viper venom clotting time mix protocol in patients with unprovoked lower limb venous 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: Phospholipid-dependent autoantibodies require precise laboratory confirmation parameters to differentiate circulating anticoagulants from coagulation factor deficiencies. This prospective diagnostic study evaluated the performance of an integrated dilute Russell’s viper venom time (dRVVT) screening and confirmation mix protocol in 70 adult patients presenting with acute, unprovoked lower limb deep vein thrombosis. Patient plasma underwent initial 1:1 mixing steps with normal pooled plasma to exclude simple factor deficiencies, 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 integrated mix-confirmation protocol achieved a diagnostic sensitivity of 93.7% and a specificity of 90.7% when cross-validated against standard international guidelines. Mixing indexes correlated positively with a history of recurrent thrombotic episodes (r = 0.48, P < 0.05). Utilizing this integrated mix loop reduces false-positive results caused by baseline variations in clotting factors, providing a cost-effective and accurate thrombophilia risk-profiling asset for specialized clinical pathology laboratories.
Keywords: Lupus anticoagulant, diluted Russell’s viper venom time, mixing studies, venous thrombosis, thrombophilia screening
Manuscript Timeline: Received: June 14, 2018; Revised: July 22, 2018; Accepted: August 11, 2018; Published: September 15, 2018