Sanquin Research, Department of Experimental Immunohematology, Amsterdam, The Netherlands.
Landsteiner Laboratory, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands.
Vox Sang. 2020 May;115(4):323-333. doi: 10.1111/vox.12894. Epub 2020 Feb 20.
In adult immune thrombocytopenia (ITP), an acquired autoimmune bleeding disorder, anti-platelet autoantibody testing may be useful as a rule-in test. Childhood ITP has different disease characteristics, and the diagnostic and prognostic value of anti-platelet antibody testing remains uncertain.
To systematically review the diagnostic accuracy of anti-platelet autoantibody testing in childhood ITP.
PubMed and EMBASE were searched for studies evaluating immunoassays in childhood ITP. Study quality was assessed (QUADAS2), and evidence was synthesized descriptively.
In total, 40 studies (1606 patients) were identified. Nine studies reported sufficient data to determine diagnostic accuracy measures. Anti-platelet IgG antibody testing showed a moderate sensitivity (0·36-0·80 platelet-associated IgG [direct test]; 0·19-0·39 circulating IgG [indirect test]). In studies that reported control data, including patients with non-immune thrombocytopenia, specificity was very good (0·80-1·00). Glycoprotein-specific immunoassays showed comparable sensitivity (three studies) and predominantly identified IgG anti-GP IIb/IIIa antibodies, with few IgG anti-GP Ib/IX antibodies. Anti-platelet IgM antibodies were identified in a substantial proportion of children (sensitivity 0·62-0·64 for direct and indirect tests).
The diagnostic evaluation of IgG and IgM anti-platelet antibodies may be useful as a rule-in test for ITP. In children with insufficient platelets for a direct test, indirect tests may be performed instead. A negative test does not rule out the diagnosis of ITP. Future studies should evaluate the value of anti-platelet antibody tests in thrombocytopenic children with suspected ITP.
在成人免疫性血小板减少症（ITP）中，一种获得性自身免疫性出血性疾病，抗血小板自身抗体检测可用作确诊试验。儿童 ITP 具有不同的疾病特征，抗血小板抗体检测的诊断和预后价值仍不确定。
系统评价抗血小板自身抗体检测在儿童 ITP 中的诊断准确性。
检索了评估儿童 ITP 免疫测定的 PubMed 和 EMBASE 数据库。评估了研究质量（QUADAS2），并进行了描述性证据综合。
共确定了 40 项研究（1606 例患者）。有 9 项研究报告了足够的数据来确定诊断准确性指标。抗血小板 IgG 抗体检测显示出中等敏感性（0.36-0.80 血小板相关 IgG[直接检测]；0.19-0.39 循环 IgG[间接检测]）。在报告对照数据的研究中，包括非免疫性血小板减少症患者，特异性非常好（0.80-1.00）。糖蛋白特异性免疫测定显示出相当的敏感性（三项研究），主要识别 IgG 抗 GP IIb/IIIa 抗体，很少识别 IgG 抗 GP Ib/IX 抗体。相当一部分儿童中存在抗血小板 IgM 抗体（直接和间接检测的敏感性分别为 0.62-0.64）。
IgG 和 IgM 抗血小板抗体的诊断评估可用作 ITP 的确诊试验。对于血小板计数不足无法进行直接检测的儿童，可以进行间接检测。阴性检测不能排除 ITP 的诊断。未来的研究应评估抗血小板抗体检测在疑似 ITP 的血小板减少儿童中的价值。
