A study of patients with viral encephalitis reveals that it can lead to serious movement problems.

Researchers at the Cleveland Clinic, Ohio, say that there may be more severe consequences to viral encephalitis than previously realised. They studied a group of 84 patients with the condition, five of whom had West Nile virus. Of these, 11 had to be admitted to neurological intensive care. And four of these developed severe movement disorders.

They experienced tremor, myoclonus (sudden jerking), chorea (writhing) and ballismus, a type of violent flinging movement. These symptoms required very heavy sedation to keep them under control. Patients not affected by movement disorders needed an average stay of 16 days in intensive care, compared to 55 days for those who were affected. One patient recovered fully, two were transferred to chronic care and the remaining one of the four is still in intensive care.

Source

American Academy of Neurology 1st April 2003