Corticosteroids for viral central nervous system infections

Purpose of review Viruses are frequent causes of central nervous system (CNS) infection. Lacking specific antiviral treatment or inadequate clinical response may lead to treatment with corticosteroids. This review describes the rationale for and clinical experience with the use of adjunctive corticosteroids for viral CNS infections. Recent findings Corticosteroids display anti-inflammatory, immunosuppressive, antiproliferative, and vasoconstrictive effects by genomic and nongenomic regulation of human cells. Recent population-based studies consistently show that empiric dexamethasone during diagnostic work-up for meningitis has neither been associated with improved outcome nor adverse effects in viral meningitis. Myelitis is most often due to noninfectious causes and standard empiric treatment includes high-dose methylprednisolone. There are no convincing data on viral myelitis to support a change of this approach. Corticosteroids have occasionally been employed in different types of viral encephalitis. Observational data and a few randomized clinical trials have not documented any substantial beneficial effects of adjunctive corticosteroids in viral encephalitis. Risks of harm with current treatment regimens remained low in published studies. Summary Except for myelitis, there are no data to support routine use of corticosteroids for viral CNS infections. Large, multidisciplinary syndromic platform trials of all-cause encephalitis may be a viable way to inform treatment guidelines.