Some authors define UCTD as an autoimmune condition with ANA, non-specific autoantibodies (i.e. anti-Ro/SSA) and non-specific clinical features (arthralgia and RP), while, in the “autoimmune” route to SLE, UCTD patients progressively developed malar rash and new SLE-specific autoantibodies, such as anti-Sm and anti-dsDNA [27, 29]. Here, CALR is linked to systemic lupus erythematosus.