GFAP and B-cell chronic lymphocytic leukemia: CAD, coronary artery disease; CLL, chronic lymphocytic leukemia; CSF, cerebrospinal fluid; DM, diabetes mellitus; DM, diabetes mellitus; FLAIR, fluid-attenuated inversion recovery; GFAP, glial fibrillary acidic protein; HLD, hyperlipidemia; HTN, hypertension; IgG, immunoglobulin G; IL-6, interleukin-6; IVIG, intravenous immunoglobulin; MRI, magnetic resonance imaging; MRI, magnetic resonance imaging; MV, mechanical ventilation; OCB, oligoclonal bands; PCR, polymerase chain reaction; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2; SWI, susceptibility-weighted imaging