Systemic lupus erythematosus and overlap: A clinician perspective

Autoimmune inflammatory rheumatic diseases, also termed as autoimmune collagen vascular diseases, as the name suggests are the group of illness arising from a combination of loss of tolerance to self-antigens and shifting of the immune system into self-destructive overdrive. These are commonly classified under six mutually exclusive diseases which include systemic lupus erythematosus (SLE), systemic sclerosis (SSc), dermatomyositis, polymyositis, rheumatoid arthritis (RA), and primary Sjögren syndrome, the so-called definitive connective tissue diseases. Undifferentiated and mixed connective tissue disease and overlap syndrome have also been added to the classification. An initially undifferentiated connective tissue disease may later evolve into a differentiated connective tissue disease. Here, we define the various connective tissue diseases and elaborate more upon SLE and its overlap, including the overlap of RA (RHUPUS).