Encephalitis, inflammation of the brain, is associated with the following signs and symptoms: fever, headache, altered mental status, neurologic deficit, hallucinations, behavioral changes, photophobia, seizures, neck stiffness (when associated with meningitis), preceding viral prodrome, recent mosquito/tick/animal bites, and/or immunocompromised state/use of immunosuppressant medications.
The presence of focal neurologic deficit and/or altered mental status is more predictive of encephalitis than meningitis.
The emergent management goal is to rule out and/or empirically treat bacterial meningitis and other treatable infectious sources such as Herpes Simplex Virus (HSV), VaricellaZoster Virus (VZV), and Cytomegalovirus (CMV); these carry significant mortality and morbidity risks. Remember to have patient's cerebrospinal fluid (CSF) specifically analyzed for etiologies such as these (i.e. via PCR).
Treat presumed encephalitis aggressively by adding acyclovir to the antibiotic/steroid regimen administered, particularly when there is altered mental status and/or focal neurologic deficit.
