C1q在自身免疫性疾病中的临床意义

Complement 1q determination for autoimmune diseases

目的探讨补体(C)1q检测对自身免疫性疾病(AID)的临床意义。方法选取2014年5月-2015年9月在南昌大学第二附属医院住院的AID患者203例[自身免疫性甲状腺疾病(AITD)86例、系统性红斑狼疮(SLE)56例、类风湿性关节炎(RA)32例、其他结缔组织病29例]及体检健康者(对照组)100名,采用免疫透射比浊法检测C1q、免疫比浊法检测C反应蛋白(CRP)、间接免疫荧光法(IIF)检测抗核抗体(ANA)和抗双链DNA(ds-DNA)抗体、线性免疫印迹法(LIA)检测抗Sm抗体,并对结果进行分析。结果与对照组比较,SLE组C1q水平下降(P<0.05),RA组C1q水平升高(P<0.05)。C1q的水平随ANA滴度升高而降低(P<0.05)。抗ds-DNA抗体(+)且抗Sm抗体(+)组C1q水平显著低于抗ds-DNA抗体(-)且抗Sm抗体(-)组(P<0.05)。CRP的水平在AID各组中均明显升高(P<0.01)。C1q与CRP间的相关系数>0.300(P<0.05),由二者的回归方程计算出C1q的临界值(COV)范围为167.42~198.37 mg/L。定性分析C1q与自身抗体的关系:AID ANA阳性组C1q<COV的异常率高于ANA阴性组,ANA(+)且抗ds-DNA抗体(+)组C1q<COV的异常率明显高于其他自身抗体分布模式组,ANA(+)且抗Sm抗体(+)或抗Sm抗体和抗dsDNA抗体同时阳性的患者C1q<COV的异常率明显升高,ANA阴性组C1q>COV的异常率达67.2%。结论 AID患者C1q水平与CRP呈中度正相关,C1q异常率与某些自身抗体的分布模式、AID患者的病情相关,C1q在AID中具有一定的临床意义。

Objective To evaluate the role of complement(C)1q determination for autoimmune diseases(AID).Methods A total of203AID patients[86cases of autoimmune thyroid disease(AITD),56cases of systemic lupus erythematosus(SLE),32cases of rheumatoid arthritis(RA)and29cases of other connective tissue diseases]and100healthy subjects(healthy control group)were enrolled from the Second Affiliated Hospital of Nanchang University from May2014to September2015.Using transmission turbidimetry,turbidimetric immunoassay,indirect immunofluorescence(IIF)and linear immunoblot assay(LIA),C1q,C-reactive protein(CRP),antinuclear antibody(ANA),anti-double-stranded DNA(ds-DNA)antibody and anti-Sm antibody were determined respectively.Results Compared with healthy control group,C1q level in SLE group was decreased(P<0.05),and that in RA group was increased(P<0.05).The level of C1q decreased with the increasing of ANA titer degrees(P<0.05).The C1q levels in anti-ds-DNA antibody positive and anti-Sm antibody positive group were lower than those in anti-ds-DNA antibody negative and anti-Sm antibody negative group(P<0.05).CRP levels in AID groups were increased(P<0.01).The correlation coefficient between C1q and CRP was>0.300(P<0.05).Regression equation showed that the range of cut-off values(COV)was167.42-198.37mg/L.For C1q and autoantibodies,the abnormal rate(C1q<COV)was higher in ANA positive group than that in ANA negative group,that in ANA positive with anti-ds-DNA positive group was higher than those of other autoantibody distribution types,and that in ANA positive with anti-Sm antibody positive or with anti-Sm and anti-ds-DNA antibodies positive increased.The abnormal rate(C1q>COV)in ANA negative group was67.2%.Conclusions For patients with AID,C1q has moderate correlation with CRP,the abnormal rate of C1q has correlations with some autoantibody distribution types and the status of patients'illness.