Marta E. Martinuzzo, Laboratorio Central, Sección Hematología-Hemostasia, Hospital Italiano de Buenos Aires; Departamento de Bioquímica Aplicada, Instituto Universitario del Hospital Italiano de Buenos Aires; Ciudad Autónoma de Buenos Aires, Argentina
Emanuel Sueldo, Laboratorio de Hemostasia, Unidad Asistencial Dr. César Milstein, Ciudad Autónoma de Buenos Aires, Argentina
Cristina Duboscq, Grupo Cooperativo Latinoamericano de Hemostasia y Trombosis (CLAHT), Montevideo, Uruguay; Hospital Británico de Buenos Aires, Buenos Aires, Argentina
José M. Ceresetto, Laboratorio de Hemostasia, Unidad Asistencial Dr. César Milstein, Ciudad Autónoma de Buenos Aires, Argentina
Marina S. López, Laboratorio Central, Sección Hematología-Hemostasia, Hospital Italiano de Buenos Aires; Departamento de Bioquímica Aplicada, Instituto Universitario del Hospital Italiano de Buenos Aires; Ciudad Autónoma de Buenos Aires, Argentina
Arias Mirta, Laboratorio de Hemostasia, Unidad Asistencial Dr. César Milstein, Ciudad Autónoma de Buenos Aires, Argentina
Introduction: In clinical practice, coagulation factors levels measurement is used to detect possible factor deficiency in patients with bleeding manifestations or to explain the origin of prolonged routine coagulation tests results. Objectives: The aim was to evaluate factor VIII (FVIII), factor IX (FIX), and Factor XI (FXI) assay performed with silica clotting time confirm (SCTC) reagent in LA positive (AL+), normal controls (NC), and factors deficient (D) samples. Materials and methods: Citrated plasmas: 73 AL+, 45 NC; 77 D: 40 FVIII, 22 FIX, and 15 FXI. FVIII, FIX, and FXI D. (1) SynthASil activated partial thromboplastin time (APTT) (SYNT); (2) SCTC (3) FVIII chromogenic assay (FVIIICHROM). Results: NC: slightly lower FVIIISCTC than FVIIISYNT and FIXSYNT than FIXSCTC. No differences FXISYNT versus FXISCTC. D: No differences between FVIIISCTC, FVIIISYNT, and FVIIICHROM, or FXISYNT versus FXISCTC. FIX SYNT is slightly higher than FIXSCTC. NC+C: FVIII, FIX and FXI SCTC-SYNT r > 0.970. AL+: 36.7% FVIIISYNT, 66.1% FIXSYNT, and 86.2% FXISYNT nonparallel dilution curves. FVIIISYNT1/40, FVIIISCTC, and FVIII: CHROM comparable results. FVIIISCTC-FVIIICHROM, r: 0.949, FVIIISCTC-FVIIISYNT, r: 0.759. Low FIXSCTC-FIXSYNT, no correlation FXISCTC-FXISYNT. Conclusion: FVIII, FIX, and FXI assays with SCTC seem to be useful to measure factor levels in AL+ samples.
Keywords: Coagulation factors dosage. Lupus anticoagulant. Silica clotting time confirm.
