Two patients with acute rotavirus encephalitis associated with cerebellar signs and symptoms.

Rotavirus, one of the major causes of severe gastroenteritis in children, occasionally causes central nervous system complications. Recently several patients with acute encephalitis/encephalopathy due to rotavirus associated with cerebellar signs and symptoms have been reported. The condition is characterized by disturbances of consciousness at onset and cerebellar signs and symptoms such as hypotonia, ataxia, dysmetria, and speech disorders, including mutism, slow speech, and dysarthria at convalescence. We report two patients (3-year-old girl, 2-year-old boy) who developed acute encephalitis due to rotavirus and showed cerebellar signs and symptoms. Both patients had characteristic history of consciousness disturbances subsequent to several days of diarrhea, vomiting and fever, and cerebellar symptoms such as hypotonia, ataxia, dysmetria, and speech disorders during the recovery period. Electroencephalography showed diffuse high-voltage delta wave activity in each patient. Brain magnetic resonance imaging showed cerebellar edema in the acute phase followed by cerebellar atrophy on follow-up images in both patients. In the first patient, diffusion-weighted images (DWI) revealed high signals at the left cerebellar peduncle region and apparent diffusion coefficient (ADC) maps showed decreased ADC values of the lesion in the acute phase. The first patient had dysmetria at 1-year follow-up. However, she had normal motor and cognitive functions and could lead her daily life without impairment. In the second patient, no further symptoms were apparent at 1-year follow-up. Acute encephalitis/encephalopathy due to rotavirus with cerebellar signs and symptoms might be diagnosed on DWI, by demonstrating decreased ADC values in acute phase.