抗核抗体筛查试验与特异性抗体确认试验的相关性研究

Correlation between screening assay of antinuclear antibody and confirmatory assay of specific antibody

【摘要】目的分析探讨抗核抗体（ANA）筛查试验与特异性抗体确认试验的相关性。方法用间接免疫荧光法（IIF）作为ANA筛查试验，用免疫印迹法（uA）作为抗核抗体谱（ANAs）特异性抗体确认试验，对500份临床就诊患者血清标本进行检测分析，并根据IIF-ANA和LIA-ANAs检测结果分为4组（IIF-ANA^＋／LIA-ANAs^＋组、IIF-ANA^＋／LIA-ANAs^-组、IIF-ANA^-／LIA-ANAs^＋组、IIF-ANA^-／LIA-ANAs^-组）。同时收集IIF-ANA^-／LIA-ANAs^＋组标本，使用ELISA、双向免疫扩散法（DID）进行特异性抗体复查。结果500份患者的标本中IIF-ANA^＋／LIA-ANAs^＋组为247份，IIF-ANA^＋／LIA-ANAs^-组为86份，IIF-ANA^-／LIA-ANAs^-组为152份，IIF-ANA^-／LIA-ANAs^＋组为15份。IIF-ANA^＋／LIA-ANAs^＋组中IIF-ANA滴度以≥1：1280为主，占48.2％，1：80—1：160占23.9％，1：320—1：640占27.9％。在167例IIF-ANA^-患者中LIA-ANAs^＋占9.0％（15／167），15份IIF-ANA^-／LIA-ANAs^＋标本中：包括11份抗SSA抗体和抗Ro52抗体阳性，并与ELISA、DID法复查结果基本-致；抗组蛋白（Histone）、抗scl-70、抗Jo-1、抗线粒体-M2（AMA-M2）抗体阳性各1份。LIA-ANAs与ELISA、DID的阳性符合率为100％、69％。且IIF-ANA^-／LIA-ANAs^＋组患者经临床资料分析明确诊断自身免疫病（AID）者为8例。86份为IIF-ANA^＋／LIA-ANAs^-的标本，以1：80—1：160的滴度为主（50.0％），荧光模式以均质型（H）为主（36.1％），其与IIF-ANA^＋／LIA-ANAs^＋组比较[1：80—1：160的滴度占23.9％，荧光模式均质型（H）占17.0％]，差异有统计学意义（X^2=20.47、12.42，P均〈0.05）。结论ANA临床检测中可先以筛查试验进行检测，若阳性，再进行特异性抗体确认试验。但是，对于临床疑似AID的患者，无论ANA初筛试验阴性与否，均需进行各种针对特异性抗体的确认试验；各种特异性抗体的确认试验不能完全替代ANA的筛查试验。

Objective To investigate the correlation between screening assay of antinuclear antibody （ANA） and confirmatory assay of specific antibody. Methods Five hundred clinical patients＇ serum samples were detected by indirect immunofluorescence （IIF） for screening assay of ANAs and line immunoassay （LIA） for confirmatory assay of specific ANAs. According to the results of IIF-ANA and LIA- ANAs, 500 samples were divided into 4 groups ： IIF-ANA^＋/LIA-ANAs^＋ group, IIF-ANA^＋/LIA-ANAs^- group, IIF-ANA^-/LIA-ANAs^＋ group and IIF-ANA^-/LIA-ANAs^- group. The samples in IIF-ANA^-/LIA-ANAs^＋ group were collected and rechecked by ELISA and DID for detection of specific ANAs. Results Five hundred clinical samples were identified including 247 cases of IIF-ANA^＋/LIA-ANAs^＋, 86 cases of IIF-ANA^＋/LIA-ANAs^-, 152 cases of IIF-ANA^ -/LIA-ANAs^- and 15 cases of IIF-ANA^-/LIA-ANAs^＋. In IIF-ANA^＋/LIA-ANAs^＋ group, 48.2% ,23.9% and 27.9% patients had the titre of IIF-ANA 1：1 280, 1： 80-1：160 and 1：320-1：640. Fifteen cases of LIA-ANAs^＋ were identified in 167 cases of IIF-ANA（9.0%）. Among 15 cases of IIF-ANA^-/LIA-ANAs^＋, 11 positive cases were identified as anti-SSA and anti-Ro52 positive, which were rechecked by ELISA and DID, and the results were consistent with the prior detection. Other positive cases were identified including 1 case of anti-Histone, 1 case of anti-Scl-70, 1 case of anti-Jo-1 and 1 case of anti-AMA-M2. The positive consistent rates between LIA-ANAs and ELISA, DID were 100%, 69% respectively. And 8 cases of IIF-ANA^-/LIA-ANAs^＋ patients were diagnosed with autoimmune disease after clinical data analysis. Among 86 cases of IIF-ANA^＋/LIA-ANAs^- , 50.0% and 36.1% patients had the titre of 1： 80—1：160 and homogeneous fluorescence pattern respectively. There was a significant difference in IIF-ANA^＋/LIA-ANAs^- group and IIF-ANA^＋/LIA-ANAs^＋（X^2= 20.47, 12.42, P 〈 .05）. Conclusions It is recommend that specific antinuclear antibodies can be used once screening assay of ANA is positive. But for clinically suspected AIDS patients, it is necessary to detect for specific antinuclear antibodies regardless of the result of screening assay of ANA. The confirmatory assay of specific antinuclear antibody could not replace the screening assay of antinuclear antibody.