RT Journal Article SR Electronic T1 Randomised prospective trial to assess the clinical utility of multianalyte assay panel with complement activation products for the diagnosis of SLE JF Lupus Science & Medicine JO Lupus Sci Med Lupus Sci Med FD Lupus Foundation of America SP e000349 DO 10.1136/lupus-2019-000349 VO 6 IS 1 A1 Daniel J Wallace A1 Roberta Vezza Alexander A1 Tyler O'Malley A1 Arezou Khosroshahi A1 Mehrnaz Hojjati A1 Konstantinos Loupasakis A1 Jeffrey Alper A1 Yvonne Sherrer A1 Maria Fondal A1 Rajesh Kataria A1 Tami Powell A1 Claudia Ibarra A1 Sonali Narain A1 Elena Massarotti A1 Arthur Weinstein A1 Thierry Dervieux YR 2019 UL http://lupus.bmj.com/content/6/1/e000349.abstract AB Objective We compared the physician-assessed diagnostic likelihood of SLE resulting from standard diagnosis laboratory testing (SDLT) to that resulting from multianalyte assay panel (MAP) with cell-bound complement activation products (MAP/CB-CAPs), which reports a two-tiered index test result having 80% sensitivity and 86% specificity for SLE.Methods Patients (n=145) with a history of positive antinuclear antibody status were evaluated clinically by rheumatologists and randomised to SDLT arm (tests ordered at the discretion of the rheumatologists) or to MAP/CB-CAPs testing arm. The primary endpoint was based on the change in the physician likelihood of SLE on a five-point Likert scale collected before and after testing. Changes in pharmacological treatment based on laboratory results were assessed in both arms. Statistical analysis consisted of Wilcoxon and Fisher’s exact tests.Results At enrolment, patients randomised to SDLT (n=73, age=48±2 years, 94% females) and MAP/CB-CAPs testing arms (n=72, 50±2 years, 93% females) presented with similar pretest likelihood of SLE (1.42±0.06 vs 1.46±0.06 points, respectively; p=0.68). Post-test likelihood of SLE resulting from randomisation in the MAP/CB-CAPs testing arm was significantly lower than that resulting from randomisation to SDLT arm on review of test results (−0.44±0.10 points vs −0.19±0.07 points) and at the 12-week follow-up visit (−0.61±0.10 points vs −0.31±0.10 points) (p<0.05). Among patients randomised to the MAP/CB-CAPs testing arm, two-tiered positive test results associated significantly with initiation of prednisone (p=0.034).Conclusion Our data suggest that MAP/CB-CAPs testing has clinical utility in facilitating SLE diagnosis and treatment decisions.