Complement component 3 levels in cerebrospinal fluid and serum.

<p>(A) Comparison of cerebrospinal fluid (CSF) and complement component 3 (C3) level between neuropsychiatric systemic lupus erythematosus (NPSLE) and non-NPSLE. (B) Comparison of CSF C3 level among the subsets of NPSLE. ACS, acute confusional state; non-ACS, diffuse NPSLE other than ACS; Focal, focal NPSLE. (C) Comparison of serum C3 level between NPSLE and non-NPSLE. (D) Correlation between serum C3 level and CSF C3 level. In (A), (B), and (C), data are shown as box plots. The boxes indicate the upper and lower interquartile range (IQR), the lines within the boxes indicate the median, the whiskers indicate the minimum and maximum IQR. Each dot represents an individual sample. Statistical analysis was performed using the Mann-Whitney <i>U</i>-test. In (D), statistical analysis was performed using Spearman’s rank correlation test.