Bickerstaff's brainstem encephalitis with overlapping Guillain-Barré syndrome: Usefulness of sequential nerve conduction studies

Bickerstaff's brainstem encephalitis (BBE) is a rare immune-mediated disorder characterized by ophthalmoplegia, ataxia and disturbance of consciousness, which may overlap with Guillain-Barré syndrome (GBS) if there is additional limb weakness. We report a 7-month-old boy presented with ophthalmoplegia followed by a rapidly ascending paralysis of all four limbs and disturbance of consciousness. The initial impression was BBE with overlapping GBS. This was supported by sequential nerve conduction study (NCS) findings compatible with an acute inflammatory demyelinating polyneuropathy (AIDP). He received intravenous pulse methylprednisolone, intravenous immunoglobulin and plasmapharesis with complete clinical recovery after 6 weeks of illness and improved NCS findings from week 16. This is the first case of paediatric BBE with overlapping GBS with an AIDP subtype of GBS. It expands the clinical spectrum of this condition in children. Our case highlights the importance of sequential NCS in paediatric BBE with overlapping GBS for accurate electrophysiological diagnosis and prognosis particularly if the first NCS findings are not informative.