Some Patients Classified With UCTD Meet Criteria for SLE

When a team of investigators applied the 2019 European Alliance of Associations for Rheumatology (EULAR)/American College of Rheumatology (ACR) classification criteria for systemic lupus erythematosus (SLE) to a cohort of female patients previously described as having undifferentiated connective tissue disease (UCTD), they found that up to 17% of these patients met the criteria for SLE.

When admitted to the study, none of these 133 women met classification criteria for other defined systemic connective tissue disease. After the researchers applied the 2019 EULAR/ACR classification criteria, they found that 22 patients (17%) fulfilled these criteria for SLE.

“Patients classified as having SLE had significantly higher frequencies of mucocutaneous manifestations (23% versus 5%; P = 0.007), arthritis (59% versus 17%; P < 0.001), isolated urine abnormalities (18% versus 1%; P < 0.001), and highly specific antibodies (50% versus 15%; P < 0.001) compared to the other patients with UCTD,” the authors wrote. “At follow-up, these patients were statistically significantly more likely to also meet the 1997 ACR revised SLE criteria and the Systemic Lupus International Collaborating Clinics (SLICC) criteria (18.2% versus 1.8%; P < 0.001) compared to the other UCTD patients.”

The investigators concluded, “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.”

—Rebecca Mashaw

Reference:
Radin M, Schreiber K, Cecchi I, et al. Impact of the 2019 European Alliance of Associations for Rheumatology/American College of Rrheumatology classification criteria for systemic lupus erythematosus in a multicenter cohort study of 133 women with undifferentiated connective tissue disease.  Arthritis Care Res. 2021;73(12):1804-1808