Department of Clinical Laboratory Science, Division of Health Science, Yamaguchi University Graduate School of Medicine, Ube, Yamaguchi 755-8505, Japan.
Diagn Microbiol Infect Dis. 2012 Nov;74(3):230-5. doi: 10.1016/j.diagmicrobio.2012.06.028. Epub 2012 Aug 16.
Conventional IgG-ELISA methods for diagnosing cat scratch disease (CSD) caused by Bartonella hensela are still poor in sensitivity and specificity, which generally employ bacterial whole-cell proteins or N-lauroyl-sarcosine-insoluble proteins as the antigen. By Western blot analysis, we found that sarcosine-soluble fraction of proteins (SSP) showed highly specific reaction to immunofluorescence assay (IFA)-positive sera obtained from CSD patients compared with the above antigens. Clinical utility of the new ELISA employing SSP was evaluated using sera from 118 patients with clinically suspected CSD (sera positive by IFA: titers ≥ 1:256, n = 46; negative: titers <128, n = 72) and 88 sera from healthy individuals. Sensitivity and specificity of distinguishing IFA-positive patients from healthy individuals were 95.7% and 97.7%, respectively. Fifteen discordant results were observed (13 ELISA(+)/IFA(-); 2 ELISA(-)/IFA(+)). However, all 15 sera reacted with SSP by Western blot analysis, indicating superiority of the new ELISA over IFA. The ELISA employing SSP greatly improved the accuracy of diagnosing CSD.
用于诊断由巴尔通体引起的猫抓病（CSD）的常规 IgG-ELISA 方法的灵敏度和特异性仍然较差，通常使用细菌全细胞蛋白或 N-月桂酰肌氨酸不溶性蛋白作为抗原。通过 Western blot 分析，我们发现与上述抗原相比，蛋白质的肌氨酸可溶部分（SSP）在与 IFA 阳性的 CSD 患者血清的免疫荧光分析（IFA）中显示出高度特异性反应。使用来自 118 例临床疑似 CSD 患者的血清（IFA 阳性：滴度≥1：256，n=46；阴性：滴度<128，n=72）和 88 例健康个体的血清评估了使用 SSP 的新 ELISA 的临床实用性。将 IFA 阳性患者与健康个体区分开来的灵敏度和特异性分别为 95.7%和 97.7%。观察到 15 个不一致的结果（13 个 ELISA（+）/IFA（-）；2 个 ELISA（-）/IFA（+））。然而，所有 15 个血清均通过 Western blot 分析与 SSP 反应，表明新 ELISA 优于 IFA。使用 SSP 的 ELISA 大大提高了诊断 CSD 的准确性。
