New-Onset Refractory Status Epilepticus Mimicking Herpes Virus Encephalitis
A 41-year-old man presented with a parainfectious syndrome characterized by low-grade fever and vomiting. Within 3 days, he experienced increasingly complex partial epileptic seizures, rapidly changing from tonic-clonic seizures to generalized SE, requiring intubation and admission to the intensive care unit. The patient had borderline intellectual functioning, possibly the expression of very mild perinatal posthypoxic encephalopathy. Clinical testing at the time of admission (as compared with neuroimaging and electroenchephalograpic studies which had been performed when the patient was a child) did not disclose any anatomic brain changes, pathology, or abnormal electric activity. No seizures were ever reported until the onset of SE.\nThe neurological examination, performed in the intensive care unit, revealed no cranial nerve or focal changes, or meningism. Because first-line anticonvulsants were not able to achieve the clinical remission of SE, intravenous anesthetic anticonvulsants were required. Intravenous infusions of propofol or thiopental were used to maintain the patient in an electrographic burst-suppression pattern, while enteral antiepileptic medications were titrated to therapeutic doses (e.g. valproic acid, clobazam, topiramate, phenobarbital, carbamazepine, and levetiracetam) [, ]. Extensive laboratory analyses, including virological, immunological, paraneoplastic, mitochondrial and endocrine tests were performed on blood and CSF with no evidence of infectious, inflammatory, mitochondrial, autoimmune, neoplastic and paraneoplastic pathology. No elevated proteins or pleocytosis were detected in CSF. Brain MRI, carried out 3 days after SE onset, showed signal hyperintensity of the temporal lobe bilaterally and symmetrically in T2 and FLAIR sequences, with involvement of both the cortex and white matter, deep into the hippocampus and pulvinar (fig. ). Signs of laminar necrosis were detected in the superior and medium temporal giri bilaterally (fig. ). Magnetic resonance diffusion-weighted images, including apparent diffusion coefficient mapping, permitted us to identify the presence of vasogenic edema (fig. ). Although some brain MRI findings strongly suggested herpes simplex virus (HSV) encephalitis (i.e. topography of lesions and cortical involvement), the absence of MRI signs of parenchymal hemorrhagic necrosis along with the absence of pleocytosis and hyperproteinorrachia in CSF and viral HSV1 and HSV6 RNA in blood and CSF did not permit the confirmation of that diagnosis. Therefore, a presumptive diagnosis of encephalitis with SE was considered, and acyclovir was empirically added to antibiotics (ceftriaxone, vancomycin) and steroids.\nDuring the following days, each time the tapering of the maximal dose of intravenous anesthetic anticonvulsants was tried, SE began again. Follow-up brain MRI studies, performed within 4 weeks, demonstrated an unvaried neuroradiological picture, but with a reduction of vasogenic edema in the temporal lobes (fig. ) and more evident involvement of the pulvinar bilaterally (fig. ).\nThe patient died 41 days after the onset of SE and an autopsy was not performed. Written informed consent could not be obtained from the deceased patient. Nonetheless, we acquired written informed consent from the patient's parents for the publication of this case report and the accompanying images.