Decades of clinical research have yielded only one useful subset in systemic lupus erythematosus (SLE), which consists of those patients where lupus nephritis is the principal manifestation. Genetic studies have revealed numerous lupus-associated polymorphisms, but none of any practical use. In contrast to these disappointments, multiple molecular and cellular studies in recent years have unexpectedly begun to converge on the pivotal finding that SLE consists of a small number of distinct immunopathological entities, and that these can be identified by standard methods alone or in combination. Moreover, the same subsets can be identified in patient groups with different clinical diagnoses, such as Sjogren’s syndrome, systemic sclerosis, or even rheumatoid arthritis. The results of these studies are not yet fully consistent with one another but gain in importance as multiple targeted therapies for lupus emerge. Thus, I will argue that we are standing on the threshold of a new taxonomy for the systemic autoimmune diseases, based on molecular and cellular analyses, and that such a taxonomy will facilitate more personalised therapeutic approaches.

Learning Objectives

• Explain the limitations of classifications based on clinical criteria

• Discuss recent research demonstrating the clustering of SLE and other systemic autoimmune diseases into distinct subgroups based on molecular and cellular markers

• Describe how a new taxonomy of the systemic autoimmune diseases will faciliate personalised therapeutic approaches