An anti-nuclear antibody-negative patient with systemic lupus erythematosus (SLE) accompanied with anti-ribosomal P antibody (anti-P).

We report a case of an anti-nuclear antibody (ANA)-negative patient with systemic lupus erythematosus (SLE) accompanied with anti-phospholipid antibody syndrome (APS) and lupus nephritis (LN). Histological examination of placenta obtained by an artificially-induced abortion revealed multiple thromboses in the placental villi. Histology of biopsied kidney tissue revealed minimal change with deposits of immunoglobulin and complement. Anti-ribosomal P antibodies (anti-P) and lupus anticoagulant (LAC) were positive and anti-double stranded DNA antibody (anti-DNA) showed only a slightly positive titer in her serum. The intensity of proteinuria of the patient was correlated with the anti-P, but not anti-DNA titers.