| Encephalitis lethargica | |
|---|---|
| Other names | Economo's disease; von Economo's encephalitis[1] |
 | |
| An illustration from von Economo's Die Encephalitis lethargica (1918) showing brain tissue of an affected monkey seen under a microscope | |
| Specialty | Neurology |
| Symptoms | Fever, headache, double vision, psychosis, lethargy[2] |
| Complications | Coma, Parkinson's, epilepsy[2][1] |
| Usual onset | Within 2 months of exposure[1] |
| Causes | Unknown[2] |
| Diagnostic method | Based on symptoms after ruling out other potential causes[1] |
| Treatment | Symptomatic treatment, levodopa[2] |
| Prognosis | Frequent long-term disability[1] |
| Frequency | Currently rare[1] |
| Deaths | 30% mortality[1] |
Encephalitis lethargica (EL) is a form of brain inflamation initially characterized by fever, headache, double vision, psychosis, and lethargy.[2] In most cases, this gradually results in some degree of coma.[1] Parkinson's or epilepsy may develop in the years following the initial illness.[2][1]
The cause is unknown.[2] Proposal include an infection such as influenza or an autoimmune process.[1] In at least some cases, the disease appeared to spread between people.[1] In pregnancy, the baby may also be affected.[1] The underlying mechanism involved inflammation of specific parts of the brain, the mesencephalon and the diencephalon.[1] Diagnosis was based on symptoms after ruling out other potential cases.[1]
Treatment is based on the symptoms.[2] Levodopa may result in significant, though temporary improvement.[2][1] Outcomes depend on the associated complications.[2] About a third of people died.[3] Many of those who survived were left with permanent disabled.[1]
Outbreaks of disease occurred around the world starting in 1916 until 1930 and affected about 5 million people.[2][1][3] Outbreaks are believed to have occurred prior, and less than 20 cases have been documented since.[1] The condition was first described by in 1917 by Constantin von Economo and Jean-René Cruchet.[4][5][1] It has also been called "sleeping sickness" or "sleepy sickness";[1] though is not related to tsetse fly-transmitted sleeping sickness.[3]
References edit
- ^ a b c d e f g h i j k l m n o p q r s t Berger JR, Vilensky JA (2014). "Encephalitis lethargica (von Economo's encephalitis)". Handbook of Clinical Neurology. 123: 745–761. doi:10.1016/B978-0-444-53488-0.00036-5. ISBN 9780444534880. PMID 25015515.
- ^ a b c d e f g h i j k "Encephalitis Lethargica Information Page | National Institute of Neurological Disorders and Stroke". www.ninds.nih.gov. Archived from the original on 4 January 2017. Retrieved 6 July 2021.
- ^ a b c Harley, Trevor A. (18 February 2021). The Science of Consciousness. Cambridge University Press. p. 282. ISBN 978-1-107-12528-5. Archived from the original on 28 August 2021. Retrieved 6 July 2021.
- ^ Economo's disease at Who Named It?
- ^ von Economo, K. (May 10, 1917). "Die Encephalitis lethargica". Wiener klinische Wochenschrift [Vienna clinical weekly] (in German). 30. Leipzig and Vienna: Franz Deuticke 1918: 581–585.