Department of Pathology & Laboratory Medicine, The University of Texas Health Science Center at Houston, Houston, Texas.
J Clin Lab Anal. 2014 Jan;28(1):42-6. doi: 10.1002/jcla.21641. Epub 2013 Dec 27.
Capillary zone electrophoresis (CZE) is a newer method of performing serum protein electrophoresis and is considered to be faster and more efficient than agarose gel method. We decided to evaluate CZE as an efficient screening tool for monoclonal gammopathies, and we began recommending immunofixation studies in cases with such minor/subtle distortions to avoid missing monoclonal gammopathies.
We evaluated 163 serum protein agarose gel electrophoresis (SPAGE) samples between October and November 2011, and 447 serum protein CZE (SPCZE) samples between January 2012 to February 2012 and August 2012 to September 2012.
Immunofixation studies were recommended in 51 of 163 cases (31.3%) performed by SPAGE, and in 274 of 447 cases (61.3%) performed by SPCZE. While using SPAGE, of the 51 cases recommended for immunofixation (24 were performed to date), six cases (25.0%) were positive for monoclonal gammopathy. In contrast, while using SPCZE, of the 274 cases recommended for immunofixation (118 were performed to date), 18 cases (15.2%) were positive for monoclonal gammopathy. Using the SPCZE method, of these 18 cases, five (27.8%) had minor/subtle distortions without obvious peaks. Our recommendation rate for immunofixation studies has thus almost doubled (61.3% vs. 31.3%) with the adoption of SPCZE. Yet, using SPCZE has not translated to detecting more cases of true monoclonal gammopathies.
Therefore, we conclude that there is a high false-positive rate for monoclonal gammopathy using CE alone.
毛细管区带电泳（CZE）是一种新的血清蛋白电泳方法，被认为比琼脂糖凝胶法更快、更有效。我们决定评估 CZE 作为单克隆丙种球蛋白病的有效筛查工具，并开始建议在出现微小/细微扭曲的情况下进行免疫固定研究，以避免漏诊单克隆丙种球蛋白病。
我们评估了 2011 年 10 月至 11 月期间的 163 例血清蛋白琼脂糖凝胶电泳（SPAGE）样本，以及 2012 年 1 月至 2 月和 2012 年 8 月至 9 月期间的 447 例血清蛋白毛细管区带电泳（SPCZE）样本。
SPAGE 检测的 163 例中，有 51 例（31.3%）建议进行免疫固定研究，SPCZE 检测的 447 例中，有 274 例（61.3%）建议进行免疫固定研究。使用 SPAGE 时，建议进行免疫固定的 51 例（其中 24 例已进行）中，有 6 例（25.0%）为单克隆丙种球蛋白病阳性。相比之下，使用 SPCZE 时，建议进行免疫固定的 274 例（其中 118 例已进行）中，有 18 例（15.2%）为单克隆丙种球蛋白病阳性。使用 SPCZE 方法，这 18 例中，有 5 例（27.8%）微小/细微扭曲无明显峰。因此，采用 SPCZE 后，我们建议进行免疫固定研究的比例几乎翻了一番（61.3% vs. 31.3%）。然而，使用 SPCZE 并没有检测到更多真正的单克隆丙种球蛋白病病例。
因此，我们得出结论，单独使用 CZE 检测单克隆丙种球蛋白病存在高假阳性率。
