Beth Israel Deaconess Medical Center, 185 Pilgrim Rd, Palmer 111, Boston, MA, USA.
Clin Auton Res. 2019 Feb;29(1):31-39. doi: 10.1007/s10286-018-0540-0. Epub 2018 Jun 28.
Electrochemical skin conductance (ESC) is a non-invasive test of sweat function developed as a potential marker of small fiber neuropathy. Here we systematically review the evolution of this device and the data obtained from studies of ESC across different diseases.
Electronic databases, including MEDLINE, and Google Scholar were searched through to February 2018. The search strategy included the following terms: "electrochemical skin conductance," "EZSCAN," and "Sudoscan." The data values provided by each paper were extracted, where available, and input into tabular and figure data for direct comparison.
Thirty-seven studies were included this systematic review. ESC did not change by age or gender, and there was significant variability in ESC values between diseases, some of which exceeded control values. Longitudinal studies of disease demonstrated changes in ESC that were not biologically plausible. Of the 37 studies assessed, 25 received support from the device manufacturer. The extracted data did not agree with other published normative values. Prior studies do not support claims that ESC is a measure of small fiber sensory function or autonomic function.
Although many papers report significant differences in ESC values between disease and control subjects, the compiled data assessed in this review raises questions about the technique. Many of the published results violate biologic plausibility. A single funding source with a vested interest in the study outcomes has supported most of the studies. Normative values are inconsistent across publications, and large combined data sets do not support a high sensitivity and specificity. Finally, there is insufficient evidence supporting the claim that Sudoscan tests sudomotor or sensory nerve fiber function.
电化学皮肤电导（ESC）是一种非侵入性的汗液功能测试方法，被开发为小纤维神经病的潜在标志物。本文系统回顾了该设备的发展历程，以及在不同疾病中使用 ESC 进行研究获得的数据。
通过电子数据库（包括 MEDLINE 和 Google Scholar）搜索至 2018 年 2 月的文献。检索策略包括以下术语：“电化学皮肤电导”、“EZSCAN”和“Sudoscan”。如果有可用的数据值，将从各篇论文中提取并输入表格和图形数据中进行直接比较。
本系统评价纳入了 37 项研究。ESC 不受年龄和性别影响，且在不同疾病之间 ESC 值存在显著差异，其中一些疾病的 ESC 值超过了对照值。疾病的纵向研究显示 ESC 发生了变化，但这些变化在生物学上是不合理的。在评估的 37 项研究中，有 25 项得到了设备制造商的支持。提取的数据与其他已发表的正常值不一致。先前的研究不支持 ESC 是小纤维感觉功能或自主功能的测量方法这一说法。
尽管许多论文报告了疾病和对照组之间 ESC 值存在显著差异，但本文汇总的数据对该技术提出了质疑。许多已发表的结果违反了生物学合理性。一个对研究结果有既得利益的单一资金来源支持了大多数研究。不同出版物中的正常值不一致，且大型综合数据集也不支持高灵敏度和特异性。最后，没有足够的证据支持 Sudoscan 测试可用于检测汗腺或感觉神经纤维功能的说法。
