ISSN 2997-1036
International Journal of Hematology | Vol. 7, No. 3, March 2016 | pp. 17–24
DOI: 10.46882/2016/IJH/000075
Original Article
Title: Screening for lupus anticoagulant utilizing an integrated dRVVT and Silica Clot Time ratio algorithm in unprovoked 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: Guidelines for diagnosing antiphospholipid antibodies recommend utilizing at least two separate phospholipid-dependent clotting assays to minimize false-negative results. This prospective study evaluated the diagnostic efficiency of combining the diluted Russell’s viper venom time (dRVVT) with the Silica Clot Time (SCT) in an integrated screening algorithm for 76 adult patients presenting with unprovoked lower limb venous thrombosis. Both test methodologies included initial screening steps followed by high-phospholipid confirmation steps to establish diagnostic ratios. Lupus anticoagulant presence was confirmed in 23.6% (18 of 76) of the thromboembolic cohort. The diluted Russell's venom assay demonstrated an isolated sensitivity of 77.7%, missing 4 positive patients who were subsequently captured by the Silica Clot Time protocol. The combined dual-assay testing algorithm achieved an overall diagnostic sensitivity of 94.4% and a specificity of 91.3%. Utilizing both mechanisms reduces test gaps caused by varying autoantibody specificities, improving the accuracy of long-term thrombophilia risk profiling.
Keywords: Lupus anticoagulant, diluted Russell’s viper venom time, Silica Clot Time, venous thrombosis, thrombophilia screening
Manuscript Timeline: Received: December 04, 2015; Revised: January 15, 2016; Accepted: February 10, 2016; Published: March 17, 2016