New Classification Criteria for Systemic Lupus Erythematosus

Abstract

Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease with highly variable clinical and immunological manifestations. Classification and diagnosis of SLE are complicated by the multi-organ nature of the disease and by our incomplete understanding of its pathophysiology. The 1997 update of the 1982 American College of Rheumatology (ACR) criteria for SLE has been widely used for classification of SLE. In order to improve clinical relevance and early diagnosis, the Systemic Lupus Erythematosus International Collaborating Clinics (SLICC) group suggested the 2012 SLICC criteria. These sets of classification criteria have unweighted lists of various serological and clinical findings typical of SLE, can be fulfilled by reaching a sum score of points. The only exception is biopsy-proven lupus nephritis with autoantibodies in the 2012 SLICC criteria. In an attempt to overcome limitations of the previous sets of SLE classification criteria, the new 2019 SLE European League Against Rheumatism/American College of Rheumatology (EULAR/ACR) classification criteria for SLE have been recently published. The 2019 EULAR/ACR criteria include positive ANA at least once as obligatory entry criterion; followed by additive hierarchically clustered and weighted criteria. The structure and weighting of criteria constitute a paradigm shift in the classification of SLE. In the validation cohort, the new criteria had a sensitivity of 96.1% and specificity of 93.4%. This review attempts to delineate the history, performance and limitations of the current sets of SLE criteria.