COVID‐19 associated brain/spinal cord lesions and leptomeningeal enhancement: A meta‐analysis of the relationship to CSF SARS‐CoV‐2

ABSTRACT Background and Purpose We reviewed the literature to evaluate cerebrospinal fluid (CSF) results from patients with coronavirus disease 2019 (COVID‐19) who had neurological symptoms and had an MRI that showed (1) central nervous system (CNS) hyperintense lesions not attributed to ischemia and/or (2) leptomeningeal enhancement. We sought to determine if these findings were associated with a positive CSF severe acute respiratory syndrome associated coronavirus 2 (SARS‐CoV‐2) polymerase chain reaction (PCR). Methods We performed a systematic review of Medline and Embase from December 1, 2019 to November 18, 2020. CSF results were evaluated based on the presence/absence of (1) ≥ 1 CNS hyperintense lesion and (2) leptomeningeal enhancement. Results In 117 publications, we identified 193 patients with COVID‐19 who had an MRI of the CNS and CSF testing. There were 125 (65%) patients with CNS hyperintense lesions. Patients with CNS hyperintense lesions were significantly more likely to have a positive CSF SARS‐CoV‐2 PCR (10% [9/87] vs. 0% [0/43], p = 0.029). Of 75 patients who had a contrast MRI, there were 20 (27%) patients who had leptomeningeal enhancement. Patients with leptomeningeal enhancement were significantly more likely to have a positive CSF SARS‐CoV‐2 PCR (25% [4/16] vs. 5% [2/42], p = 0.024). Conclusion The presence of CNS hyperintense lesions or leptomeningeal enhancement on neuroimaging from patients with COVID‐19 is associated with increased likelihood of a positive CSF SARS‐CoV‐2 PCR. However, a positive CSF SARS‐CoV‐2 PCR is uncommon in patients with these neuroimaging findings, suggesting they are often related to other etiologies, such as inflammation, hypoxia, or ischemia.