Department of Clinical Biochemistry, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.
Department of Clinical Biochemistry, Herlev and Gentofte Hospital, Copenhagen University Hospital, Herlev, Denmark.
Scand J Clin Lab Invest. 2020 Dec;80(8):681-686. doi: 10.1080/00365513.2020.1846208. Epub 2020 Nov 13.
Subarachnoid hemorrhage (SAH) is a serious neurological event associated with high morbidity and mortality. Computed tomography of the cerebrum (CTC) is the diagnostic method of choice, but in case of negative CTC but strong suspicion of SAH, lumbar puncture with spectrophotometric analysis of cerebrospinal fluid (CSF) for xanthochromia is performed. We wanted to examine the diagnostic properties of CSF spectrophotometry for xanthochromia testing. We performed a retrospective study of the diagnostic properties of CSF analysis for xanthochromia using spectrophotometry in the diagnosis of SAH. A total of 489 CSF samples were analyzed for xanthochromia, according to international guidelines, from 2009 until 2014 and for 411 of these the patient files were retrieved and examined for final clinical diagnosis and result of CTC. One patient with SAH did not have a positive spectrophotometry report and another patient with SAH had an equivocal report. In four patients did initial CTC not correctly identify SAH. For patients with a negative CTC within six hours of symptom onset spectrophotometry for xanthochromia in the CSF had a diagnostic sensitivity of 100% and a diagnostic specificity of 98.5%. The positive predictive value was 16.7% and the negative predictive value 100%. We conclude that spectrophotometry of CSF for xanthochromia is a sensitive and specific test for diagnosing SAH. However, it seems that an initial CTC identifies almost all patients with SAH. This suggests that in our and similar diagnostic settings, lumbar puncture and testing for xanthochromia might only be relevant in very few cases, if not obsolete.
蛛网膜下腔出血（SAH）是一种严重的神经系统事件，与高发病率和死亡率相关。大脑计算机断层扫描（CTC）是首选的诊断方法，但在 CTC 阴性但强烈怀疑 SAH 的情况下，会进行腰椎穿刺并对脑脊液（CSF）进行分光光度分析以检测黄变。我们想研究 CSF 分光光度法检测黄变的诊断特性。我们进行了一项回顾性研究，评估了 CSF 分析在诊断 SAH 中使用分光光度法检测黄变的诊断特性。根据国际指南，我们对 2009 年至 2014 年期间共 489 份 CSF 样本进行了黄变分光光度分析，其中 411 份样本的患者病历被检索并进行了最终临床诊断和 CTC 结果检查。一位 SAH 患者的分光光度报告为阴性，另一位 SAH 患者的报告为不确定。四位患者的初始 CTC 未正确识别 SAH。对于症状发作后 6 小时内 CTC 为阴性的患者，CSF 分光光度法检测黄变的诊断灵敏度为 100%，特异性为 98.5%。阳性预测值为 16.7%，阴性预测值为 100%。我们的结论是，CSF 分光光度法检测黄变是诊断 SAH 的一种敏感和特异的方法。然而，似乎初始 CTC 可以识别几乎所有的 SAH 患者。这表明在我们和类似的诊断环境中，腰椎穿刺和黄变检测可能只在极少数情况下（如果不是过时的话）才有意义。
