Impact of the 2019 European Alliance of Associations for Rheumatology/American College of Rheumatology Classification Criteria for Systemic Lupus Erythematosus in a Multicenter Cohort Study of 133 Women With Undifferentiated Connective Tissue Disease.

When applying the 2019 EULAR/ACR criteria for SLE in a cohort of patients with UCTD, we observed that in up to 17% of cases the original classification could be challenged. New implementation will help to identify earlier patients at higher risk of developing more severe CTD manifestations.