[Bickerstaff's encephalitis]. / Romboencefalitis de Bickerstaff.

INTRODUCTION: The clinical and radiological findings in a case of Bickerstaff encephalitis are described and the relationship with Miller Fisher and Guillain Barré syndromes are discussed. CLINICAL CASE: Subsequently to a respiratory infection,a 44-year-old male developed external ophthalmoplegia and cerebellar-like ataxia; his condition deteriorated and he suffered consciousness disturbances and absent tendon reflexes were noted. An MRI scan was performed showing a lesion affecting the brainstem. The cerebrospinal fluid (CSF) revealed albuminocytologic dissociation and the presence of oligoclonal bands. He received high doses of intravenous immunoglobulins and five months later, he had completely recovered. A follow up MRI scan demonstrated complete resolution of the lesion. CONCLUSIONS: The initial condition was diagnosed as Bickerstaff brainstem encephalitis (BBE) with overlapping peripheral nervous system semiology. The presence during the acute phase of oligoclonal bands in CSF, which decreased with the clinical improvement, supports the hypothesis than an autoimmune mechanism may function in its pathogenesis. Our case suggests that intravenous immunoglobulins therapy should be considered in patients with BBE.