Meningoencephalitis

Meningoencephalitis
Classification and external resources
ICD-10	G04
ICD-9	323.9
DiseasesDB	22354
MeSH	D888590

Meningoencephalitis (pronounced /mɛˌnɪŋɡɵ.ɛnˌsɛfəˈlaɪtɨs/, from Greek: meninges- membranes; enkephalos brain; and -itis inflammation) is a medical condition that simultaneously resembles both meningitis, which is an infection or inflammation of the meninges, and encephalitis, which is an infection or inflammation of the brain.

Causes

Causative organisms include protozoans, viral and bacterial pathogens.

Specific types include:

Bacterial

• Listeria monocytogenes
• Neisseria meningitidis
• Rickettsia prowazekii

Viral

• Tick-borne meningoencephalitis
• West Nile virus
• Mumps, a relatively common cause of meningoencephalitis. However, most cases are mild, and mumps meningoencephalitis generally does not result in death or neurologic sequalae.^[1]
• HIV, a very small number of individuals exhibit meningoencephalitis at the primary stage of infection.^[2][3]

Other/multiple

• Granulomatous meningoencephalitis
• Other causes include antibodies targeting amyloid beta peptide proteins which have been used during research on Alzheimer's disease.^[4]
• The fungus, Cryptococcus neoformans, can be symptomatically manifested within the CNS as meningoencephalitis with hydrocephalus being a very characteristic finding due to the unique thick polysaccharide capsule of the organism.

Protozoal

• Primary amoebic meningoencephalitis e.g., Naegleria fowleri, Balamuthia mandrillaris, Sappinia diploidea.
• Trypanosoma brucei
• Toxoplasma gondii (sporozoa) (immunocompromised patients)

Ameobic pathogens exist as free-living protozoans. Nevertheless, these pathogens cause rare and uncommon CNS infections. N. fowleri produces primary amebic meningoencephalitis (PAM). The symptoms of PAM are indistinguishable from acute bacterial meningitis. Other amebae cause granulomatous amebic encephalitis (GAE), which is a more subacute and can even a non-symptomatic chronic infection. Ameobic meningoencephalitis can mimic a brain abscess, aseptic or chronic meningitis, or CNS malignancy.^[5]

Prognosis

The disease is associated with high rates of mortality and severe morbidity.^{[citation needed]}

Notable cases

It was the claimed cause of death of the popular British TV presenter Christopher Price.^[6]

In May, 2009 former Premier of New South Wales (Australia) Morris Iemma was admitted to hospital with meningoencephalitis^[7].

See also

• meningism
• ameoba
• Primary amoebic meningoencephalitis
• encephalitis

References

1. ^ Bruyn HB, Sexton HM, Brainerd HD (March 1957). "Mumps meningoencephalitis; a clinical review of 119 cases with one death". Calif Med 86 (3): 153–60. PMC 1512024. PMID 13404512. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1512024. 
2. ^ Newton, PJ; Newsholme, W; Brink, NS; Manji, H; Williams, IG; Miller, RF (2002). "Acute meningoencephalitis and meningitis due to primary HIV infection". BMJ (Clinical research ed.) 325 (7374): 1225–7. PMC 1124692. PMID 12446542. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1124692. 
3. ^ Del Saz, SV; Sued, O; Falcó, V; Agüero, F; Crespo, M; Pumarola, T; Curran, A; Gatell, JM et al. (2008). "Acute meningoencephalitis due to human immunodeficiency virus type 1 infection in 13 patients: clinical description and follow-up". Journal of neurovirology 14 (6): 474–9. doi:10.1080/13550280802195367. PMID 19037815. 
4. ^ Orgogozo JM, Gilman S, Dartigues JF, et al. (2003-07-08). "Subacute meningoencephalitis in a subset of patients with AD after Aß42 immunization". Neurology 61 (1): 46–54. doi:10.1212/01.WNL.0000073623.84147.A8. PMID 12847155. http://www.neurology.org/cgi/content/abstract/61/1/46?ck=nck. Retrieved 2008-05-01. 
5. ^ Amebic Meningoencephalitis at eMedicine
6. ^ "Presenter Killed by Rare Infection". BBC News. 2002-06-19. http://news.bbc.co.uk/1/hi/entertainment/tv_and_radio/2053119.stm. Retrieved 2008-05-01. 
7. ^ Silmalis, Linda (2009-06-28). "Paralysed Iemma fights to walk again". The Sunday Telegraph. http://www.news.com.au/story/0,27574,25702400-421,00.html. Retrieved 2009-06-28.