[Acute encephalitis presenting with symmetrical involvement of the bilateral basal ganglia].

A 8-year-old girl was hospitalized with consciousness disturbance and involuntary movements five days after the onset of fever. Cranial MRI revealed symmetrical involvement of the bilateral basal ganglia with elevated ADC mapping, suggesting vasogenic edema.Her clinical symptoms improved with methylprednisolone pulse therapy without neurological sequelae. The rapid antigen test for group A beta-hemolytic streptococcus was positive and serum ASO was elevated. Myelin basic protein in cerebrospinal fluid was elevated. We suggest that the pathophysiological mechanism in the present case was not necrotic/cytotoxic but autoimmune inflammation, which is compatible with acute disseminated encephalomyelitis associated with streptococcal infection.