Case Description:A 59-year-old woman with history of large granular lymphocytic leukemia with neutropenia presented with a few days of malaise,headache,stiff neck,fevers,nausea,vomiting, confusion, and diplopia.She was empirically treated for presumed meningoencephalitIs.Lumbar puncture revealed WBC count of 703/μL with neutrophilic predominance(76%) and protein of 69 mg/dL.MRI obtained four days after fever onset showed subtle increased signal within the dorsal pons and midbrain on the T2-weighted and FLAIR sequences and subtle contrast enhancement in left midbrain and left medial temporal lobes on T1 sequences.She was then transferred to Tufts Medical Center(TMC) where she developed left gaze deviation with extensor posturing and tonic rigidity concerning for status epilepticus.She was orally intubated,sedated with propofol,and received therapeutic doses of both fosphenytoin and levetiracetam.EEG on hospital day 2 revealed bilateral periodic epileptiform discharges that organized into ictal continuum.Burst suppression was achieved with addition of lacosamide and pentobarbital.CSF analysis on hospital day 6 showed WBC count of 140/μL with lymphocytic predominance(74%) and protein of 163g/dL.MRI brain obtained twelve days after fever onset revealed interval development of marked increased signal within the bilateral deep gray nuclei,mesial temporal lobes,external capsules, and brainstem on the T2-weighted and FLAIR sequences as well as a new intraparenchymal hemorrhage centered within the mid pons.Restricted diffusion was seen along the corticospinal tracts bilaterally.EEE IgM antibody was positive in the serum and CSF.Post-mortem pathology demonstrated perivascular lymphocytic cuffing with diffuse microglial activation in the brain parenchyma,lymphocytic infiltration of the leptomeninges and severe ischemic changes in the hippocampus.