A case of Bickerstaff brainstem encephalitis associated with spindle coma and decorticate posture

Abstract

A 25-years-old man experienced fever and diarrhea. Ten days later he noticed difficulty walking (day 1). On admission neurological examination revealed lethargy, dysarthria and weakness of limbs. Oculocephalic response was not be elicited and extensor toe signs were positive. In spite of treatment with aciclovir and methylprednisolone, he continued to show progressive deterioration developing to coma with decorticate posture. Autonomic symptoms (hyperhidrosis, hypersalivation and fever) and groaning were observed. Brain magnetic resonance image and brainstem evoked potential presented no abnormality, but electroencephalographic study showed a spindle pattern indicating spindle coma. Laboratory tests including cerebrospinal fluids showed no specific results. High-dose immunoglobulin was administered from day 6, and his consciousness level improved. External ophthalomoplegia and ataxic gait were observed after he became more alert. Because he had IgG type anti-GQ1b antibodies in the serum, a diagnosis was made of Bickerstaff's brainstem encephalitis (BBE). Six months after discharge he had complete resolution of his symptoms. This is the first report of spindle coma observed in a case of serologically confirmed BBE.