Identification of a clinical subset of systemic lupus erythematosus by antibodies to the sm antigen

Abstract
The clinical and renal histologic attributes of 135 systemic lupus erythematosus (SLE) patients with DNA and/or Sm antibodies were compared to determine if the presence of the Sm antibodies served as a marker for a specific subset of SLE. Although Raynaud's phenomenon was more frequent in patients with Sm antibodies (P < 0.005), serious central nervous system disease was over three times as common in patients with DNA antibodies (P < 0.005). Only one of 23 patients with Sm antibodies had diffuse proliferative glomerulonephritis on renal biopsy, whereas 6 of 14 patients with only DNA antibodies had this histologic finding (P = 0.01). The Sm antibody system may therefore identify a subset of SLE patients with milder central nervous system and renal disease.