Progressive multifocal leukoencephalopathy (PML), caused by infection with John Cunningham polyoma virus (JCPyV) in immune-compromised patients, is a serious demyelinating disease of the central nervous system. This disease often leads to major neurological impairments and consecutive disability. No effective treatment for PML has been found as yet. As JCPyV-PCR of the cerebrospinal fluid (CSF) may be negative in some cases, a reliable diagnosis might prove to be difficult as well. So far, two case reports suggested CSF-tau to be a promising biomarker for PML. Our study included 10 patients with assured diagnosis of PML and varying underlying diseases. In all but one the CSF-tau concentration was normal. Our results indicate that CSF-tau is not an appropriate biomarker for PML.

中文翻译：

---

进行性多灶性白质脑病患者脑脊液中的 Tau 蛋白浓度未升高

进行性多灶性白质脑病 (PML) 由免疫受损患者感染约翰·坎宁安多瘤病毒 (JCPyV) 引起，是一种严重的中枢神经系统脱髓鞘疾病。这种疾病通常会导致严重的神经损伤和连续残疾。尚未发现 PML 的有效治疗方法。由于在某些情况下脑脊液 (CSF) 的 JCPyV-PCR 可能为阴性，因此也可能难以进行可靠的诊断。到目前为止，有两个病例报告表明 CSF-tau 是 PML 的一个有前途的生物标志物。我们的研究包括 10 名确诊为 PML 和各种潜在疾病的患者。除了一个之外，所有的 CSF-tau 浓度都是正常的。我们的结果表明 CSF-tau 不是 PML 的合适生物标志物。