Encephalitis after hepatitis B vaccination - Recurrent disseminated encephalitis or MS?

Objective: To describe clinical and MRI features of patients with a disease suggestive of CNS inflammation after hepatitis B vaccination. Methods: Eig ht patients with confirmed CNS inflammation occurring less than 10 Reeks af ter hepatitis B vaccination are described. They received follow-up clinical ly and on MRI for a mean period of 18 months. Results: Clinical and MRI fin dings were compatible with acute disseminated encephalomyelitis. However, c linical follow-up, repeated MRI, or both showed the persistence of inflamma tory activity, which makes this encephalitis more suggestive of MS than of acute disseminated encephalomyelitis. Conclusion: The persistent inflammato ry activity observed clinically and on MRI in these patients is comparable with that usually observed in RIS, Epidemiologic studies are currently test ing the hypothesis of a triggering role of hepatitis B vaccination in CNS d emyelination.