IL6 and COVID-19: that the IL-6 and TNF-alpha CSF/serum ratios and indices may be worthwhile being investigated in future studies on CSF findings in COVID-19 as potential markers of CNS infection with SARS-CoV-2, given that the only patient positive also exhibited increased SARS-CoV-2-IgG, -IgM and -IgA AI as well as marked CSF pleocytosis; (vii).