Meningoencephalitis resembles both meningitis, which is an infection or inflammation of the meninges, and encephalitis, which is an infection or inflammation of the brain.
Causative organisms include protozoans, viral and bacterial pathogens.
Bacterial agents include: Listeria monocytogenes, Neisseria meningitidis, Rickettsia prowazekii, Mycoplasma pneumoniae, Tuberculosis, Borrelia (Lyme disease), Leptospirosis, and H. Influenzae.
Viral agents include: Tick-borne meningoencephalitis, West Nile virus, Measles, Epstein-Barr virus, Varicella-zoster virus, Enterovirus, Herpes simplex virus type 1, Herpes simplex virus type 2, mumps, HIV
Mumps is a relatively common cause of meningoencephalitis, but is mild, and usually does not result in death or neurologic sequelae.
Cryptococcus neoformans fungus infection of the CNS can manifest as meningoencephalitis with hydrocephalus.
Ameobic pathogens cause rare and uncommon CNS infections, and ameobic meningoencephalitis can mimic a brain abscess, aseptic or chronic meningitis, or CNS malignancy.
Meningoencephalitis is associated with high rates of mortality and severe morbidity.
The cause of acute meningoencephalitis is not identified in approximately 50% of cases.
Metagenomic next generation sequencing allows a comprehensive spectrum of potential causes from viral, bacterial, fungal, and parasitic identification by a single essay.
Failure to have a timely diagnosis in such a disease contributes to poor patient outcomes, increased anxiety, and a high cost burden to the healthcare system.