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.