Purpose of review: To compare the recently published European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) classification criteria for SLE with the Systemic Lupus International Collaborating Centers (SLICC) criteria and the earlier ACR criteria, focusing on their key concepts.
Recent findings: Although the SLICC criteria introduced numbers of new criteria items, the new EULAR/ACR criteria added only noninfectious fever, based on an early SLE cohort study and an SLE patient survey, and condensed hematological, mucocutaneous and neurological items. Whereas the SLICC criteria maintained the overall structure familiar from the ACR criteria, the EULAR /ACR criteria use antinuclear antibodies (ANA) as an obligatory entry criterion, have weighted criteria and group these in domains. Where the SLICC criteria greatly increased sensitivity, losing some specificity, the EULAR/ACR criteria increased specificity again, for excellent classification criteria performance.
Summary: Despite differences in structure and statistical performance, the EULAR/ACR and SLICC criteria agree on the importance of both immunological and clinical findings, on the high impact of lupus nephritis by histology, and on most clinical items.