Nimo R E, Carmel R
Department of Medicine, University of Southern California School of Medicine, Los Angeles 90033.
Am J Clin Pathol. 1987 Dec;88(6):729-33. doi: 10.1093/ajcp/88.6.729.
Increasing the ratio of test serum to the intrinsic factor (IF) antigen should increase the sensitivity of anti-IF antibody assay, a useful, specific tool for diagnosing pernicious anemia. We therefore designed an assay in which this ratio was increased 25-fold over that of our current standard assay and 1,000-fold over that of most described methods. This assay was then compared with our standard assay, with one of the original assays, and with a commercial kit. Both of our assays, especially the newer sensitive method, detected antibody in much greater dilutions of positive serum than the other assays. The sensitive assay also detected antibody in 17% of pernicious anemia sera negative by our standard technique. We calculated that anti-IF antibody can be detected with the sensitive assay in 78% of our patients with pernicious anemia, compared with 73% by our standard assay, 65% by the commercial kit, and 61% by the original method of Gottlieb and colleagues. No antibody was detected in 35 control sera with the new assay, which suggests that the increased sensitivity did not come at the expense of diminished specificity. The increased sensitivity enhances the value of the anti-IF antibody as a major screening and diagnostic tool in pernicious anemia.
提高检测血清与内因子（IF）抗原的比例应能提高抗IF抗体检测的灵敏度，这是诊断恶性贫血的一种有用且特异的工具。因此，我们设计了一种检测方法，其中该比例比我们当前的标准检测方法提高了25倍，比大多数已描述的方法提高了1000倍。然后将该检测方法与我们的标准检测方法、一种原始检测方法以及一种商业试剂盒进行比较。我们的两种检测方法，尤其是更新的敏感方法，在阳性血清的更高稀释度下检测到的抗体比其他检测方法多。敏感检测方法还在我们标准技术检测为阴性的17%的恶性贫血血清中检测到了抗体。我们计算得出，使用敏感检测方法可在78%的恶性贫血患者中检测到抗IF抗体，相比之下，我们的标准检测方法为73%，商业试剂盒为65%，Gottlieb及其同事的原始方法为61%。新检测方法在35份对照血清中未检测到抗体，这表明灵敏度的提高并未以特异性降低为代价。灵敏度的提高增强了抗IF抗体作为恶性贫血主要筛查和诊断工具的价值。
