线性免疫印迹法在抗核抗体间接免疫荧光法筛查阴性标本中的临床意义

Detection of specific anti-nuclear antibodies by line immunoassay in indirect immunofluorescence-negative serum samples

目的探讨采用线性免疫印迹法（LIA）在抗核抗体（ANA）间接免疫荧光法（1IF）筛查阴性标本中进行抗核抗体谱（ANAs）特异性抗体检测的价值和临床意义。方法对461例IIF—ANA阴性临床血清标本采用线性免疫印迹法进行15种ANAs特异性抗体（LIA—ANAs）检测。结果216例自身免疫性疾病（AID）组标本中LIA—ANAs阳性数为100例，占46．30％，高于非AID组（2000％）；AID组LIA—ANAs阳性结果按灰度强度分，LIA（3＋）、LIA（2＋）、LIA（1＋）、LIA（±）的阳性率均高于非AID组。差异均有统计学意义（均P〈0．05）。AID组中ANAs特异性抗体中的抗Ro-52、抗SS—A、抗Sm、抗nRNP／Sm、抗SS—B抗体、抗dsDNA和抗rRNP抗体的阳性率分别为2．31％～18．06％，高于非AID组，差异有统计学意义（P〈0．05）。AID组中ANAs特异性抗体阳性强度LIA（1＋）＋LIA（4-）的阳性率高于LIA（3＋）＋LIA（2＋）的阳性率，差异有统计学意义（P〈0．01）。抗nRNP／Sm、抗Ro-52、抗SS—A和抗SSB抗体在AID组中阳性率的差异无统计学意义（P〉0．05）；系统性红斑狼疮（SLE）与非SLE比较，抗Sm和抗dsDNA抗体阳性率高于各组，差异均有统计学意义（均P〈0．05）。结论ANA间接免疫荧光法筛查容易导致AID患者部分具有重要临床意义的ANAs特异性抗体漏检，IIF—ANA的检测不能完全代替LIA—ANAs的检测，对于临床疑似AID的患者，无论IIF—ANA检测结果阴性与否。均需进行ANAs特异性抗体检测。

Objective To evaluate the application of line immunoassay for detection of specific anti-nuclear antibody （ANA） in indirect immnofluorescence （llF）-negative serum samples. Methods Total 461 IIF-ANA-consecutive samples were tested by IIF for 15 specific anti-nuclear antibodies and their clinical significance was analyzed. Results In 216 patients of autoimmune disease （AID） LIA-ANAs＋ was identified in 100 serum samples with a positive rate of 46.30%, which was higher than that of non-AID patients（20.00% ）. In AID patients the positive rate of LIA（3＋）, LIA（2＋）, LIA（I＋） and LIA（＋ ） were higher than those of non-AID patients （P〈0.05）. The positive rates of anti-Ro-52, anti-SSA, anti-dsDNA, anti-AMA-M2, anti-Sin, anti-SSB, anti-dsDNA and anti-rRNP antibodies in AID group were from 2.31% -18.06 %, which were higher than those of non-AID group（P〈0.05 ）. The positive rate of LIA（I＋）＋LIA（ ＋ ） grayscale were higher than LIA（3＋）＋LIA（2＋） in AID group（x2= 18.402, P = 0.000）. There were no differences in positive rate of aiti-nRNP/Sm, anti-Ro-52, anti-SS-A and anti-SSB between two groups （P 〉0.05）. The positive rate of anti-Sm and anti-dsDNA in systemic lupus erythematosus （SLE） were higher than those of non-SLE （P〈0.05）. Conclusion It is recommend to detect serum specific antinuclear antibodies with line immunoassay whether the ANA is positive or negative shown by screening assay of IIF.