Febrile seizures – First symptom of Rasmussenencephalitis

Introduction: Rasmussen encephalitis is a rare immune-mediated brain disorder. Intractable seizures and progressive neurologic dysfunction are based on unilateral hemispheric atrophy. Aetiology is not yet clarified. In brain biopsy lymphocytic infiltration and microglial nodules are evident. Microbiological agens are not found. Therapeutic options to stop the brain atrophy are immunmodulation or immunosuppression and should be started in the early phase of the disease. Seizures are mostly intractable despite aggressive treatment. Long term outcome depends on reaction to therapeutic interventions.

Case history: 3rd child of a healthy, unrelated couple from Austria. Pregnancy and delivery were uneventful. Vaccination was done as recommended. On the 2nd birthday a focal febrile seizure occurred. There were no initial signs of hemiparesis. CSF cell count, protein and glucose was normal and no microbiological agent was found. EEG showed slow δ activity on the right temporal side with focal spike waves. On MRI frontal edema and diffuse signal alterations on T2 weighted images were present. Two weeks later the child developed intractable seizures. A diagnostic brain biopsy of the right frontal lobe showed lymphocytic infiltration. Seizures could be successfully treated with the combination of phenytoin, levetiracetam and clobazam. Three months later mild brain atrophy of the right hemisphere was seen and treatment with immunglobulins was initiated. At this time mild hemiparesis on the left side and moderate ataxia were noticed. The child could crawl but not walk without help. Speech was normal.

Conclusions: Rasmussen encephalitis is an orphan disease with limited therapeutic interventions and can be present at a very young age. Early exact diagnosis and early immunmodulation therapy may improve the prognosis of this still poorly understood condition.