Rabello A, Luquetti A O, Moreira E F, Gadelha M de F, dos Santos J A, de Melo L, Schwind P
Centro de Pesquisas René Rachou-Fiocruz, MG, Brasil.
Mem Inst Oswaldo Cruz. 1999 Jan-Feb;94(1):77-82. doi: 10.1590/s0074-02761999000100016.
The ID-Chagas test is a particle gel immunoassay (PaGIA). Red coloured particles are sensitised with three different synthetic peptides representing antigen sequences of Trypanosoma cruzi: Ag2, TcD and TcE. When these particles are mixed with serum containing specific antibodies, they agglutinate. The reaction mixture is centrifuged through a gel filtration matrix allowing free agglutinated particles to remain trapped on the top or distributed within the gel. The result can be read visually. In order to investigate the ability of the ID-PaGIA to discriminate negative and positive sera, 111 negative and 119 positive, collected in four different Brazilian institutions, were tested by each of the participants. All sera were previously classified as positive or negative according to results obtained with three conventional tests (indirect immunofluorescence, indirect hemaglutination, and enzyme linked immunosorbent assay). Sensitivity rates of ID-PaGIA varied from 95.7% to 97.4% with mean sensitivity of 96.8% and specificity rates varied from 93.8 to 98.8% with mean specificity of 94.6%. The overall Kappa test was 0.94. The assay presents as advantages the simplicity of operation and the reaction time of 20 min. In this study, ID-PaGIA showed to be highly sensitive and specific.
ID-查加斯检测是一种颗粒凝胶免疫测定法（PaGIA）。红色颗粒用代表克氏锥虫抗原序列的三种不同合成肽进行致敏：Ag2、TcD和TcE。当这些颗粒与含有特异性抗体的血清混合时，它们会发生凝集。将反应混合物通过凝胶过滤基质进行离心，使游离的凝集颗粒滞留在顶部或分布在凝胶内。结果可以通过肉眼读取。为了研究ID-PaGIA区分阴性和阳性血清的能力，来自四个不同巴西机构收集的111份阴性血清和119份阳性血清由每位参与者进行检测。所有血清先前已根据三种传统检测方法（间接免疫荧光法、间接血凝法和酶联免疫吸附测定法）获得的结果分为阳性或阴性。ID-PaGIA的灵敏度率在95.7%至97.4%之间，平均灵敏度为96.8%，特异性率在93.8%至98.8%之间，平均特异性为94.6%。总体kappa检验为0.94。该检测方法的优点是操作简单且反应时间为20分钟。在本研究中，ID-PaGIA显示出高度的敏感性和特异性。
