Bickerstaff brainstem encephalitis with Guillain-Barré syndrome overlap following chlamydia infection.

Bickerstaff brainstem encephalitis (BBE) is a rare autoimmune encephalitis characterised by ataxia, ophthalmoplegia and altered consciousness. An overlap between BBE with Guillain-Barré syndrome (GBS) shows similar clinical and immunological features. We report a case of BBE with GBS overlap secondary to Chlamydia pneumoniae infection. The triad of altered consciousness, ataxia and ophthalmoplegia were present in the patient. The investigations included cerebrospinal fluid cytoalbuminological dissociation, nerve conduction test that showed prolonged or absent F wave latencies, hyperintensity in the left occipital region on brain MRI and diffuse slow activity on the electroencephalogram. The chlamydia serology was positive indicating a postinfectious cause of BBE syndrome. He required artificial ventilation as his consciousness level deteriorated with tetraparesis, oropharyngeal and respiratory muscle weakness. Immunotherapy with intravenous immunoglobulin and methylprednisolone was commenced. He made good recovery with the treatment. Prompt recognition of this rare condition following chlamydia infection is important to guide the management.