[A severe episode in a patient with recurrent disseminated acute encephalitis due to vaccination against hepatitis B. For or against vaccination?].

INTRODUCTION

Several reports of new cases of CNS demyelination or reactivation of MS after hepatitis B vaccination have raised the possibility of a causal relationship. Conversely, some authors have concluded that the risk of developing a demyelinating CNS event after a hepatitis B vaccination is unknown.

PATIENTS AND METHODS

We have observed a 40 year old man, with diabetes mellitus (DM) type 1 and a previous history of recurrent acute demyelinating encephalomyelitis (rADEM). The patient had experienced three episodes of neurological dysfunction and he fulfilled the criteria for definite clinical MS but MRI showed demyelinating lesions in the pons and cerebellum without MRI criteria of MS. CSF analysis showed oligoclonal banding. The patient had been clinically stable during the last 6 years. Yearly MRI during this period had not shown any new disease activity. He was admitted in our MS Clinic due to dizziness, nausea, vomiting and diplopia, 6 weeks after the first of the two injections for hepatitis B vaccine after participating in the national programme of vaccination in DM type 1 patients. Clinical examination showed intranuclear ophtalmoplegia, visual loss in the left eye and worsening of the previous cerebellar and pyramidal signs. MRI showed an increase in the old lesions with high intensity signals on T2 weighted sequences with post gadolinium enhancement on T1 weighted sequences located in the brainstem and mesencephalon. The patient s diabetes mellitus deteriorated with ketoacidosis that needed increased doses of insulin. His condition worsened and he developed partial motor seizures. He improved 15 days later but he still had involvement of the cerebellar and pyramidal systems and occasional dizziness.

CONCLUSIONS

As pointed out by some authors and in view of this observation, it would seem reasonable, as a precautionary measure, to avoid hepatitis B vaccination in patients with a personal or family history of symptoms suggestive of a demyelinating disease of the CNS.