[Case of infantile autism with pediatric Wernicke's encephalopathy due to severe eating disorder].

Wernicke's encephalopathy (WE) or thiamine deficiency is fatal if left untreated. We report a case of a 3-year-old boy with infantile autism and a severe eating disorder who developed WE after 3 weeks of starvation without thiamine supplementation. The eating disorder started when he entered preschool. He presented with unconsciousness and a cluster of seizures. Cranial magnetic resonance imaging (MRI) showed high-intensity signal changes in the basal ganglia on T2-weighted images and fluid-attenuated inversion recovery (FLAIR). Treatment with high-dose intravenous thiamine was effective. Pediatric patients with WE tends to show no typical symptoms or brain lesions on MRI as seen in adult WE patients typically along alcoholics. Brain lesions similar to those in hypoxia or mitochondrial diseases such as Leigh's encephalopathy, are observed in patients with pediatric WE, and this makes diagnosis difficult. WE should be considered when patients with severe eating disorders present with unconsciousness and/or frequent seizures, and show basal ganglia lesions on MRI, differential diagnosis should include WE.