Bickerstaff's Brainstem Encephalitis

Bickerstaff's brainstem encephalitis is an immune disorder of unknown aetiology with acute, progressive cranial nerve dysfunction, associated with cerebellar ataxia and coma. Bickerstaff brainstem encephalitis is associated with the presence of anti-GQ1b antibodies.¹

• It may result in apnoea and a reversible brain death picture.
• No structural brain damage has been demonstrated.
• Bickerstaff reported eight patients who, in addition to acute ophthalmoplegia (diplopia) and ataxia, showed drowsiness, extensor plantar responses or hemisensory loss.²

There is a clinical continuum between Bickerstaff brainstem encephalitis and Fisher syndrome.³

• Very rare. Mostly reported in adults but cases affecting children have also been reported.⁴
• Very often follows preceding illness and an association with certain infections, including cytomegalovirus, Campylobacter jejuni, typhoid fever and Mycoplasma pneumoniae, has been documented.^1,5,6

• Acute diplopia
• Ataxia
• Pyramidal tract paralysis
• Disturbance of consciousness
• Headache is common
• Progressive, symmetrical ophthalmoplegia, ataxia and either disturbance of consciousness or hyperreflexia
• Facial palsy, extensor plantar reflex, pupillary abnormality, nystagmus and bulbar palsy

MRI scan abnormalities; multiple sclerosis, Behcet's disease , Lyme Disease, progressive multifocal leukoencephalopathy, sarcoidosis, Whipple's disease, listeria rhombencephalitis, vasculitis due to systemic lupus erythematosus (SLE), and acute disseminated encephalomyelitis all produce similar inflammatory lesions in the brainstem and cerebellum.⁷

• One review of 62 patients found positive serum anti-GQ1b IgG antibody in 66%, and brain abnormality on MRI scan in 30% of patients.⁸
• The presence of anti- GQ1b antibodies and an abnormal brain MRI can help to support its diagnosis but absence of anti-GQ1b antibodies and a normal MRI do not exclude the diagnosis, which remains based on clinical criteria and exclusion of other aetiologies.⁹
• Electrodiagnostic study results suggested peripheral motor axonal degeneration.

• A large number of patients have associated Guillain-Barre syndrome, suggesting that the two disorders are closely related.¹⁰
• Miller Fisher syndrome:¹¹ syndrome of ophthalmoplegia, ataxia and absent reflexes.

• Success has been achieved with treatment with steroids plus double filtration plasmapheresis¹² and also with immunoglobulin therapy.¹³
• However there are no randomised controlled trials of immunomodulatory therapy.¹⁴

• Although the initial presentation is severe, there is usually a good outcome with complete resolution.¹⁵
• Cases of recurrent Bickerstaff's brainstem encephalitis have been reported.⁹