Hegen Harald, Auer Michael, Zeileis Achim, Deisenhammer Florian
Clin Chem Lab Med. 2016 Feb;54(2):285-92. doi: 10.1515/cclm-2015-0253.
Determination of cerebrospinal fluid (CSF) total protein (TP) as well as of CSF/serum albumin quotient (Qalb) is part of the routine CSF work-up. However, currently used upper reference limits (URL) are not well validated leading to over-reporting of blood-CSF barrier dysfunction in approximately 15% of patients without neurological disease. The objective of this study was to determine age-related URL for CSF TP and Qalb in a cohort of control patients.
A total of 332 paired CSF and serum samples of patients without objective clinical and paraclinical findings of a neurological disease were analyzed for CSF TP and Qalb. CSF TP was measured by spectrophotometry and albumin in CSF and serum by nephelometry.
CSF TP concentration and Qalb significantly correlated with age. In subjects at the age of 18-70 years, median CSF TP ranged from 320 to 460 mg/L and URL defined as the 95th percentile were 530-690 mg/L. Median Qalb ranged from 4.1 to 6.1 and URL from 8.7 up to 11.0. For URL of Qalb we calculated the following formula: age/25+8.
Age-dependent URL for CSF TP and Qalb are presented here in a large cohort of control patients. They are higher than those currently recommended and this probably explains why isolated blood-CSF barrier dysfunction has been apparently over-reported. These new URL might be considered in a future revision of CSF guidelines.
脑脊液（CSF）总蛋白（TP）以及脑脊液/血清白蛋白商（Qalb）的测定是脑脊液常规检查的一部分。然而，目前使用的参考上限（URL）并未得到充分验证，导致在约15%无神经系统疾病的患者中过度报告血脑脊液屏障功能障碍。本研究的目的是确定一组对照患者中脑脊液TP和Qalb的年龄相关URL。
对332例无神经系统疾病客观临床和辅助检查结果患者的配对脑脊液和血清样本进行脑脊液TP和Qalb分析。脑脊液TP采用分光光度法测定，脑脊液和血清中的白蛋白采用散射比浊法测定。
脑脊液TP浓度和Qalb与年龄显著相关。在18至70岁的受试者中，脑脊液TP中位数范围为320至460mg/L，定义为第95百分位数的URL为530至690mg/L。Qalb中位数范围为4.1至6.1，URL为8.7至11.0。对于Qalb的URL，我们计算了以下公式：年龄/25 + 8。
本文给出了一大组对照患者中脑脊液TP和Qalb的年龄依赖性URL。它们高于目前推荐的值，这可能解释了为什么孤立的血脑脊液屏障功能障碍明显被过度报告。这些新的URL可能会在未来修订脑脊液指南时被考虑。
