Kim AHJ, et al. - Investigators estimated 155 subjects to assess the relationship between blood levels of complement split product iC3b and serum component C3 with variations in disease activity in subjects with systemic lupus erythematosus (SLE). In multilevel multiple logistic regression analyses, an independent association of relative changes in the iC3b:C3 ratio, levels of anti-double-stranded DNA (anti-dsDNA) antibodies, and use of a supraphysiologic dose of prednisone (>7.5 mg/day) with SLE disease activity was noted. They also found that iC3b:C3 ratio was significantly correlated with clinically vital improvements in disease activity.