Study on Correlation Between C_4 Decrease and Renal and Hematologic Activity Increased in Patients with Systemic Lupus Erythematosus / 中国医师杂志

ABSTRACT

Objective To determine the degree of C 4 changes at precede or coincide with changes in systemic lupus erythematosus (SLE) activity by 5 global activity indices(PGA, M-SLEDAI, M-LAI, SLAM, and M-BILAG), and to evaluate the correlation between changes in C 4 levels and SLE activity in individual organ systems.Methods 53 lupus patients were observed monthly for 1 year in a longitudinal study. Lupus disease activity rate and complement levels were measured at each visit. Disease activity rates were calculated for subgroups defined by previous or concurrent changes in C 4 levels. Logistic regression models were used to determine the significance of the correlation between recent changes in complement levels and disease activity, and between changes in C 4 levels and SLE activity increased in specific organ systems.Results Lupus disease activity occurred at 12%,25%,13% and 12% respectively on PGA,M-SLEDAI,M-LAI,SLAM and M-BILAG. Disease activity by the M-LAI were more frequent when there was a concurrent decrease in C 4. Higher disease activity rates by the SLAM were correlated with previous increases in C 4. Decreases in C 4 were correlated with a concurrent increase in renal disease activity,or related to a concurrent decrease in the hematocrit levels and platelet count.Conclusions Reducing serum in C 4 levels were not consistently correlated with SLE disease activity, decrease in C 4 was correlated with a concurrent increases in renal and hematologic SLE activity.