1. Encephalitis Lethargica Lewis Tan Maria Perwein

2. What it is Ethiology: Greek: enképhalos “brain”, Latin: lethargica „lethargic, somnolent Definition: “Encephalitis lethargica” or ”von Economo disease” is an atypical form of encephalitis, also known as a type of "sleepy sickness“ =Encephalitis that causes lethargy, uncontrollable sleep attacks and a temporary parkinson like dysfunction

3. What it is Discovery: First described in 1917 by the neurologist Constantin von Economo and the pathologist Jean-Rene Cruchet 1915-1926 an epidemic of LE spread around the world at the same time as the influenza (since then only isolated cases occur)

4. Causes Not known for certain Originally some scientist thought that EL was caused by the influenza pandemic in 1918 Von Economo concluded that the influenza virus is not related to EL at the same time

5. Causes Today’s statements: encephalitis of midbrain and BG with lymphatic infiltration EL might be immune-mediated (beneficial effects of steroid treatments many diseased people had pharyngitis and evidence linking the reaction to prior streptococcal throat that caused an immune response was found

6. Symptoms High fever Sore throat Headache Lethargy Double vision Delayed physical and mental response Sleep inversion and catatonia Muscular pain and tremors In severe cases patients may enter a coma-like state that can ultimate in death

7. Prevalences Mostly found within European countries Based on 112 cases from the years 1915 to 1940, most died within 2 weeks of EL onset  analysis revealed:  cortical damage in 75%  damage to the meninges and brainstem in 50%  Substantia Nigra in 13%

8. Differential diagnosis Trypanosomiasis (sleepy sickness) transmitted via Tsetse fly Parkinsonism Postencephalitic Parkinson Disease Narcolepsy

9. Treatment Oral and i.v.: Zolpidem and steroids artificial respiration physical, speech and occupational therapy Music therapy http://www.youtube.com/watch?v=piX-htWIh7I&feature=youtu.be

10. Any questions?

11. Sources http://www.ncbi.nlm.nih.gov/pubmed/19490429 http://www.ncbi.nlm.nih.gov/pubmed/11594935 http://en.wikipedia.org/wiki/Encephalitis_lethargica http://brain.oxfordjournals.org/content/127/1/21 http://www.medlink.com/medlinkcontent.asp