Cerebellar encephalitis in adults.

We examined 11 adult patients with cerebellar encephalitis (CE) during the acute phase of the disease and at least 12 months later. Five patients were aged between 23 and 31 years, 3 patients between 43 and 44 years and 3 patients between 60 and 64 years. Serological tests gave evidence of Epstein-Barr virus infection in 4 of the 5 young patients. Two patients had serological evidence of varicella-zoster virus reactivation, whereas the serological findings were negative in all other cases. All patients in the younger and middle age groups recovered within 3-30 weeks after onset of CE. If at all, they had only minor cerebellar deficits at the follow-up examination. Magnetic resonance imaging (MRI) examination performed at the follow-up examination was normal in all of them. In contrast, 2 of 3 patients older than 60 years had persistent cerebellar ataxia following CE. In these patients, MRI revealed infratentorial atrophy. Our data show that the clinical spectrum of CE in adults is wider than assumed so far. In addition to typical cases of CE in young male patients with good recovery, CE may also occur in older patients and give rise to persistent cerebellar ataxia.