Acute hemorrhagic leukoencephalitis in a COVID-19 patient-a case report with literature review.

PURPOSE: Acute hemorrhagic leukoencephalitis (AHLE) is a rare and severe form of acute disseminated encephalomyelitis (ADEM). Only a few reports of AHLE in coronavirus disease 2019 (COVID-19) patients have been described to date. We report a case of COVID-19-related AHLE along with a literature review describing salient clinical and imaging characteristics. METHODS: A literature search was performed on Medline (2020-present), PubMed, Cochrane Library, CINAHL, and Google scholar on 28 January 2021 for all articles published using MeSH terms "COVID-19" or "SARS-CoV-2" with "Acute hemorrhagic leukoencephalitis" or "Acute hemorrhagic encephalitis." Relevant case reports and case series describing clinical and imaging features of AHLE associated with SARS-CoV-2 infection were included, data compiled, and critically reviewed. RESULTS: Acute onset encephalopathy and rapidly deteriorating neurological status is the common clinical presentation in AHLE. CSF analysis reveals elevated proteins and lymphocytic pleocytosis. Typical neuroimaging features include multifocal, variable-sized, poorly defined cerebral white matter lesions with cortical sparing. Involvement of the brainstem, cerebellar peduncles, and deep grey matter can also occur, although rarely. Lesions are hyperintense on T2-weighted (T2W) and fluid-attenuated inversion recovery (FLAIR) images, hypointense on T1W images, and show microhemorrhages, variable diffusion restriction, and post-contrast enhancement. Extensive microhemorrhages, brainstem involvement, and gross hemorrhage often portend a poor prognosis. CONCLUSION: Heightened awareness about the clinical and imaging presentation of COVID-19-related AHLE can positively alter the outcome in a select few by enabling early diagnosis and aggressive management.

Update on Neurological Manifestations of SARS-CoV-2.

Severe acute respiratory syndrome coronavirus 2, the source of COVID-19, causes numerous clinical findings including respiratory and gastrointestinal findings. Evidence is now growing for increasing neurological symptoms. This is thought to be from direct in-situ effects in the olfactory bulb caused by the virus. Angiotensin-converting enzyme 2 receptors likely serve as a key receptor for cell entry for most coronaviridae as they are present in multiple organ tissues in the body, notably neurons, and in type 2 alveolar cells in the lung. Hematogenous spread to the nervous system has been described, with viral transmission along neuronal synapses in a retrograde fashion. The penetration of the virus to the central nervous system (CNS) allows for the resulting intracranial cytokine storm, which can result in a myriad of CNS complications. There have been reported cases of associated cerebrovascular accidents with large vessel occlusions, cerebral venous sinus thrombosis, posterior reversible encephalopathy syndrome, meningoencephalitis, acute necrotizing encephalopathy, epilepsy, and myasthenia gravis. Peripheral nervous system effects such as hyposmia, hypogeusia, ophthalmoparesis, Guillain-Barré syndrome, and motor peripheral neuropathy have also been reported. In this review, we update the clinical manifestations of COVID-19 concentrating on the neurological associations that have been described, including broad ranges in both central and peripheral nervous systems.