Résumé : Mild influenza-associated encephalitis/encephalopathy with a reversible splenial lesion is a rare entity recently reported almost exclusively in Asiatic individuals. Hallmarks of this clinical-radiological syndrome include severe encephalopathy at onset, prompt and complete recovery, minimal to absent pleocytosis and rapidly reversible involvement of the splenium of the corpus callosum. We report herein a young Caucasian child who in addition had cerebellar involvement and presented a transient mutism during the recovery phase.