Objective: The aim of this study was to determine the immunologic profile associated with disease flares in patients with systemic lupus erythematosus (SLE) and to investigate the clinical significance of any differences observed between patients during and following a flare.
Methods: Multiparameter flow cytometry was used to examine 47 immune populations within the peripheral blood of 16 healthy controls, 25 patients with clinically quiescent SLE, and 46 patients with SLE experiencing a flare at baseline and at 6- and 12-month follow-up visits. Unsupervised clustering was used to identify patients with similar immune profiles and to track changes over time.