Correlation Analysis Between Serum C5a Level And SLEDAI Score

Objective: To investigate the relationship between C5 a level and the activity of systemic lupus erythematosus(SLE)and its role in the pathogenesis of lupus nephilitis(LN).Methods: Peripheral blood was collected from 32 cases of SLE activity group,28 cases of stable group and 20 cases of healthy control group.Peripheral blood of 32 SLE patients treated with prednisone acetate combined with cyclophosphamide for 6 months was collected.60 cases of SLE were divided into lupus nephritis group and non-LN group.The serum C5 a levels were measured by ELISA method.Levels of C5 a,C3,C4,erythrocyte sedimentation rate(ESR),C-reactive protein(CRP)?immunoglobulin G(Ig G)?white blood cells(WBC),24 hour urine protein and anti-ds DNA were compared among different groups.Differences before and after treatment of the 32 cases active SLE were also had been done.Meanwhlie we analyzed the correlation between serum C5 a and other laboratory indexes as well as the SLEDAI score.Comparison of age and C5 a level among groups using variance analysis and multiple comparisons.The comparison between the two groups was performed by independent sample t test(Mann-Whitney U test when non-normal distribution was used).Paired t test was used before and after treatment in the active group.Spearman correlation test was used for correlation analysis of metrological data.Results:1.The C5 a level in the active SLE group was significantly higher than the stable group(55.17 ±24.22 vs 35.90 ±19.41 P=0.000),while there was no statistical difference was found between the stable and healthy control group(35.90 ±19.41 vs 31.62 ±10.34 P>0.05).2.There were a positive correlations between C5 a and SLEDAI scores,anti-ds DNA as well as 24 hour urinary protein quantification with statistically significance(R=0.592,P?0.01;R=0.304,P=0.018;R=0.287,P=0.026 respectively).And negtive correlation was found between C5 a and C3 with statistically significance(R=-0.328,P=0.010).No significant correlation was found between serum C5 a level and WBC(R=-0.171,P=0.130),ESR(R=-0.111,P=0.400),C-reactive protein(R=-0.132,P=0.315),immunoglobulin G(R=-0.186,P=0.154)and C4(R=-0.50,P=0.704)in SLE patients.3.The level of C5 a in LN group(59.89±27.20)was significantly higher than that in non-LN group(40.75±20.48)and healthy control group(31.62±10.34),and the differences were statistically significant(P=0.001,P=0.000).Significant difference was also found between non-LN group and healthy control group(P=0.001).After the treatment,the level of C5 a in the active SLE group was significantly decreased with statistically significance(38.05 ±19.81 vs 55.17 ±24.22 P=0.000),but still higher than the health controls(38.05 ±19.81 vs 31.62 ±10.34 P=0.002).Conclusion:1.There is a positive correlation between disease activity and C5 a level.2.C5 a level is positively correlated with LN activity.3.C5 a level can be used as an important index to evaluate disease activity and therapeutic efficacy,and to predict target organ damage.