Intensive care management of patients with viral encephalitis.

Viral encephalitis is a severe syndrome that can lead to encephalopathy, seizures, focal deficits, and neurological sequelae and death. It is mainly caused by neurotropic herpes viruses (i.e., HSV and VZV), although other pathogens may be observed in specific geographic regions or conditions. Recent advances in neuroimaging and molecular biology (PCR, metagenomics) allow for faster and more accurate etiological diagnoses, although their benefits need to be confirmed to provide guidelines for their use and interpretation. Despite intravenous acyclovir therapy and supportive care, outcomes remain poor in about two-thirds of herpes encephalitis patients requiring ICU admission. Randomized clinical trials focusing on symptomatic measures (i.e. early ICU admission, fever control, and treatment of seizures/status epilepticus) or adjunctive immunomodulatory therapies (i.e. steroids, intravenous immunoglobulins) to improve neurologic outcomes have not been conducted in the ICU setting. Large prospective multicenter studies combining clinical, electrophysiological, and neuroimaging data are needed to improve current knowledge on care pathways, long-term outcomes, and prognostication.