Brainstem Encephalitis

Clinic

• BE represents around 20% of all cases of encephalitis
• BE is a rare severe inflammation of CNS.
• It is largely associated with infectious and autoimmune causes.

Sign / Symptoms

• Ataxia
• Cranial neuropathies
• Altered levels of consciousness, and long tract involvement.

Causes

• Demyelinating diseases
• Susac syndrome
• Behcet disease
• Chronic lymphocytic inflammation with Pontine perivascular enhancement responsive to steroids (CLIPPERS)
• Hashimoto’s encephalopathy

Infectious etiologies

• Listeria monocytogenes: A common etiology of infectious rhombencephalitis.
• Enterovirus
• Flaviviruses
• Herpes viruses

It has unique clinical features includes:

• Opsoclonus-myoclonus syndrome (OMS)
• Bickerstaff encephalitis
• Paraneoplastic brainstem encephalitis

Related disease

Rhombencephalitis

		Miasm
Opsoclonus-myoclonus syndrome	Involuntary, conjugate, multi directional eye movements (Saccades) Myoclonus Ataxia, Dysarthria Irritability Dementia Altered level of consciousness
Bickerstaff encephalitis	External ophthalmoplegia Ataxia Lower limb arreflexia Extensor plantar response Disturbance of consciousness Dysarthria Hyperreflexia Limb weakness
Rhombencephalitis	Ataxia In 100% of patients with paraneoplastic syndromes and EBV In 10% of patients with Behçet Ataxia was seen in diseases that predominantly affected the cerebellum, such as subacute cerebellar degeneration and EBV encephalitis, whereas involvement of the long tracts was not noted in these patients. In contrast, the long tracts were the most commonly affected structures in patients with Behçet disease, whereas ataxia was seen in only 17%. Rostral brainstem involvement has been reported in Behçet disease. Low level of consciousness MS and Behçet disease do not have it In 17% of those with paraneoplastic syndromes In 78% of patients with Listeria Fever and meningeal signs Present in Listeria Absent in MS Fever without meningeal signs in EBV Spino-thalamic Corticospinal tracts Spasticity Weakness Slowing of rapid alternating movements Hyper reflexia Positive Babinski sign Posterior column

Note

• The main causes of OMS are paraneoplastic, post-infectious, and idiopathic; it is likely that they share an immune-mediated pathophysiology, although neuronal antibodies only occur in a subgroup of patients with OMS and breast cancer who develop Ri antibodies.
• Other paraneoplastic brainstem encephalitis can associate with Ma2 and Hu antibodies.
• Bickerstaff encephalitis frequently overlap with Miller–Fisher syndrome.
• The identification of GQ1b antibodies in both BBE and MFS suggests that they are part of the same spectrum of disease that has been designated anti-GQ1b syndrome.
• The diagnosis of CLIPPERS is mainly based on the presence of suggestive brain MRI abnormalities. However, similar MRI lesions can occur in systemic autoimmune diseases that may affect the brainstem, particularly Behçet disease or sarcoidosis, and in primary lymphoma of the central nervous system.

• Bilateral ophthalmoplegia
• Ataxia
• Areflexia
• Abnormal muscle coordination

	Ophthalmoplegia / Diplopia	Ataxia	Hypo Reflexia	Extensor Plantar Response	Coma	Dysarthria	Hyper Reflexia	Limb weakness	Nystagmus	Myoclonus	Dementia	Cerebellar ataxia	Meningitis
Bickerstaff encephalitis	+++	+++	+++	+++	+++	++	++	++
Miller–Fisher syndrome	+++	+++	+++
Rhombencephalitis					+++							+++	+++
Opsoclonus-myoclonus syndrome		+++			+++	+++			+++	+++