ISSN 2997-1036
International Journal of Hematology | Vol. 12, No. 6, June 2021 | pp. 41–48
DOI: 10.46882/2021/IJH/000136
Original Article
Title: Evaluation of baseline plasma protein S functional activity as an independent predictor of thromboembolic recurrence in active lupus nephritis
Names of Authors: E. F. Chinedu¹, G. H. Haruna², I. J. Balogun³
Authors’ Affiliations: ¹Department of Haematology, University of Nigeria Teaching Hospital, Enugu, Nigeria; ²Department of Medicine, Lagos State University Teaching Hospital, Ikeja, Nigeria; ³Department of Chemical Pathology, University of Ilorin, Ilorin, Nigeria
Abstract: Massive renal wasting of natural anticoagulant factors establishes a profound hypercoagulable state in nephrotic-range lupus nephritis, yet the clinical utility of functional protein S monitoring remains under-studied. This prospective study evaluated baseline plasma free protein S functional activity in 54 adult patients with active lupus nephritis to track its correlation with serum albumin depletion and 1-year thromboembolic recurrence outcomes. Protein S activity was quantified via chromogenic substrate assays prior to initiating immunosuppressive therapy. Severe protein S activity reduction (< 50.0%) was identified in 31.4% (17 of 54) of the patients. Multivariable Cox proportional hazards analysis revealed that baseline protein S functional activity below 50.0% was an independent predictor of acute deep vein thrombosis or pulmonary embolism within a 12-month follow-up window (hazard ratio = 3.64, P < 0.01). Protein S depression correlated inversely with serum albumin levels (r = -0.62, P < 0.001) and positively with D-dimer concentrations. Screening for functional protein S profiles provides clear prognostic utility, helping identify high-risk autoimmune nephropathy populations requiring early prophylactic anticoagulation.
Keywords: Lupus nephritis, protein S activity, hypercoagulability, albuminuria, thromboembolism
Manuscript Timeline: Received: March 14, 2021; Revised: April 25, 2021; Accepted: May 12, 2021; Published: June 19, 2021