補體活化產物與系統性紅斑狼瘡和類風濕性關節炎疾病活性之關係

The Usefulness of C3d and C4d in Assessing Disease Activity of Systemic Lupus Erythematosus and Rheumatoid Arthritis

66位系統性紅斑狼瘡患者，32位類風濕性關節炎患者，10位痛風患者，及16位正常對照組，利用酵素免疫分析法測定血中補體活化分解終產物C3d, C4d，與病人臨床疾病活性作進一步的分析。結果顯示只有C4d與紅斑狼瘡病人之疾病活性有正相關，且為狼瘡腎炎的良好指標。但在類風濕性關節炎病人，卻沒有相同的相關性。此結果改變了一般認為的補體活化產物的測定與疾病活性的相關性優於C3, C4的看法。但比較於傳統上以全自動免疫分析儀測定C3, C4，本法仍不失為一種極敏感，且能較動態的反應疾病活性的方法。

Two major complement activation products, C3d and C4d, of patients in four groups, including 66 systemic lupus erythematosus (SLE), 32 rheumatoid arthritis (RA), 10 gout and 16 normal controls, were analysed according to the EIA method and the data are compared with serum C3, C4 and indices and parameters of disease activity for SLE (SLE disease activity index and anti-ds DNA) and RA (Stoke index and C-reactive protein). The results show that only C4d gave improved correlations with the occurrence of active disease of SLE, which was also a good indicator on SLE nephritis. In contrast, the activity correlations were not observable in RA without extra-articular manifestations. The general impression that activation products better reveal disease activity should be revised. Nevertheless determining C3d and C4d according to the EIA method is still a sensitive method that provides more dynamic information to reflect the active status of the disease than do conventional complement measures.