[Movement disorders in adult-onset measles encephalitis]

There are three different neurological complications of measles infections in the brain: acute postinfectious encephalitis, acute progressive infectious encephalitis, and subacute sclerosing panencephalitis. The diagnosis of measles encephalitis (ME) is established when supported by the clinical picture, mainly of juvenile onset, and confirmed by the presence of cerebrospinal measles antibodies. Although ME is clinically characterized by progressive behavioral and mental deterioration associated with myoclonus, prior reports have suggested that adult-onset may have atypical features. We describe a 28 year-old immunocompetent man, admitted into the hospital due to a rapid motor and cognitive decline after an episode of fever and gastroenteritis. His neurological examination was significant for cognitive impairment, cervical dystonia, spontaneous and action induced myoclonus, choreiform movements, parkinsonism and ataxic gait. He was diagnosed of acute postinfectious ME based on the presence of elevated intrathecal synthesis of measles antibodies in his CSF, and a lymphocytic infiltrate of perivascular distribution without viral inclusions, with PCR negative for measles from brain biopsy. The patient continued to deteriorate to an akinetic mutism state, dying a few weeks later. Adult-onset ME is an entity rarely seen in the Western world. Although myoclonus is the most common movement disorder related to juvenile-onset ME, ataxia and other dyskinesias such as chorea, dystonia, and parkinsonism, can result from this infection when presenting in adult life.