Fortgens Philip H, Omar Fierdoz
Department of Clinical Laboratory Sciences, Division of Chemical Pathology, University of Cape Town, South Africa.
National Health Laboratory Service, Groote Schuur Hospital, South Africa.
Afr J Lab Med. 2013 Dec 3;2(1):23. doi: 10.4102/ajlm.v2i1.23. eCollection 2013.
Immunoassays are prone to interference by various substances which may cause inaccurate results. This type of interference is difficult to detect analytically.
A case of CARDIAC Troponin T Quantitative reader (Roche Diagnostics) assay failure was detected and investigated in order to ascertain the likely cause.
Patient whole blood was mixed with cardiac troponin T-positive blood, patient and control sera were denuded of immunoglobulin G by protein A-affinity chromatography and patient sera were mixed with mouse serum. Samples were analysed on a CARDIAC Troponin T Quantitative reader.
A mixture of patient whole blood and cardiac troponin T-positive blood resulted in assay failure; removal of immunoglobulin G from patient sera reversed the cardiac troponin T assay failure; the addition of mouse serum as a heterophile antibody blocking agent had no effect.
It is proposed that the interference resulting in assay failure may not be because of a heterophile antibody, but rather a result of a circulating autoantibody to cardiac troponin T, which may compete with antibody assay reagents for binding sites.
免疫测定容易受到各种物质的干扰，这可能会导致结果不准确。这种干扰在分析上很难检测到。
检测并调查一例心肌肌钙蛋白T定量分析仪（罗氏诊断公司）检测失败的病例，以确定可能的原因。
将患者全血与心肌肌钙蛋白T阳性血液混合，通过蛋白A亲和色谱法去除患者和对照血清中的免疫球蛋白G，并将患者血清与小鼠血清混合。在心肌肌钙蛋白T定量分析仪上对样本进行分析。
患者全血与心肌肌钙蛋白T阳性血液的混合物导致检测失败；从患者血清中去除免疫球蛋白G可逆转心肌肌钙蛋白T检测失败；添加小鼠血清作为嗜异性抗体阻断剂没有效果。
有人提出，导致检测失败的干扰可能不是由于嗜异性抗体，而是由于循环中的心肌肌钙蛋白T自身抗体，它可能与抗体检测试剂竞争结合位点。
