Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune College of Medicine, Jilin University, Changchun, Jilin, China.
School of life Science, Jilin University, Jilin Province, China.
J Med Virol. 2021 Jul;93(7):4247-4257. doi: 10.1002/jmv.26943. Epub 2021 Mar 25.
To provide instructive clues for clinical practice and further research of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, we analyzed the existing literature on viral neuroinvasion of SARS-CoV-2 in coronavirus disease 2019 (COVID-19) patients. To date, SARS-CoV-2 has been detected in the cerebrospinal fluid (CSF) or brain parenchyma in quite a few patients, which provide undeniable evidence for the neuroinvasive potential of this novel coronavirus. In contrast with the cerebrum and cerebellum, the detection rate of SARS-CoV-2 was higher in the olfactory system and the brainstem, both of which also showed severe microgliosis and lymphocytic infiltrations. As compared with the number of patients who underwent viral testing in the central nervous system (CNS), the number of patients showing positive results seems very small. However, it seems too early to conclude that the neuroinvasion of SARS-CoV-2 is rare in COVID-19 patients because the detection methods or sampling procedures in some studies may not be suitable or sufficient to reveal the CNS infection induced by neurotropic viruses. Moreover, the primary symptoms and/or causes of death were distinctly different among examined patients, which probably caused more conspicuous pathological changes than those due to the direct infection that usually localized to specific brain areas. Unfortunately, most autopsy studies did not provide sufficient details about neurological symptoms or suspected diagnoses of the examined patients, and the documentation of neuropathological changes was often incomplete. Given the complex pathophysiology of COVID-19 and the characteristics of neurotropic viruses, it is understandable that any study of the CNS infection may inevitably have limitations.
为了为严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）感染的临床实践和进一步研究提供有指导意义的线索，我们分析了现有关于 2019 年冠状病毒病（COVID-19）患者中 SARS-CoV-2 病毒神经入侵的文献。迄今为止，已经在相当多的患者的脑脊液（CSF）或脑组织中检测到了 SARS-CoV-2，这为这种新型冠状病毒的神经入侵潜力提供了不可否认的证据。与大脑和小脑相比，SARS-CoV-2 在嗅觉系统和脑干中的检测率更高，这两个部位也显示出严重的小胶质细胞增生和淋巴细胞浸润。与接受中枢神经系统（CNS）病毒检测的患者数量相比，呈阳性结果的患者数量似乎很少。然而，现在就得出结论认为 SARS-CoV-2 在 COVID-19 患者中很少发生神经入侵还为时过早，因为一些研究中的检测方法或采样程序可能不适合或不足以揭示神经嗜性病毒引起的中枢神经系统感染。此外，检查患者的主要症状和/或死亡原因明显不同，这可能导致比通常局限于特定脑区的直接感染更明显的病理变化。不幸的是，大多数尸检研究没有提供关于检查患者的神经症状或疑似诊断的足够详细信息，神经病理学变化的记录往往也不完整。鉴于 COVID-19 的复杂病理生理学和神经嗜性病毒的特征，任何对中枢神经系统感染的研究都不可避免地存在局限性是可以理解的。
