Acute encephalopathy with biphasic seizures and late reduced diffusion in Kawasaki disease.

Herein we describe the case of a 7-month-old girl with Kawasaki disease (KD) in whom status epilepticus with fever developed on day 3 and cluster of seizures on day 6 of illness, followed by severe disturbance of consciousness afterward. Diffusion-weighted magnetic resonance imaging on day 6 of illness showed diffuse high signals in the bilateral subcortical white matter, while electroencephalogram indicated low-voltage slow waves. This indicated acute encephalopathy with biphasic seizures and late reduced diffusion (AESD); severe neurological sequelae remained. This is the first report of AESD as a complication of KD.