What is the treatment approach for Rhombencephalitis?

Treatment Approach for Rhombencephalitis

Empiric treatment with intravenous aciclovir (10 mg/kg three times daily) and ampicillin should be started immediately in all cases of suspected rhombencephalitis, while awaiting diagnostic confirmation, as Listeria and HSV are the most common treatable causes. 1

Initial Management

• Patients with suspected rhombencephalitis require urgent neurological specialist assessment and should be managed in a setting where clinical neurological review can be obtained as soon as possible and definitely within 24 hours of referral 2
• Immediate neuroimaging with MRI (preferred) or CT should be performed, as nearly 100% of patients with rhombencephalitis have abnormal brain MRI findings 1, 3
• Lumbar puncture should be performed to obtain CSF for analysis, as 75% of patients with rhombencephalitis have CSF pleocytosis 1
• Blood cultures should be obtained before starting antimicrobial therapy, as they are crucial for diagnosing Listeria rhombencephalitis 1

Antimicrobial Therapy

For Suspected Viral Etiology:

• Intravenous aciclovir at 10 mg/kg three times daily should be started within 6 hours of admission if viral encephalitis is suspected 2
• For immunocompetent adults, continue aciclovir for 14-21 days for confirmed HSV encephalitis 2
• For VZV encephalitis, intravenous aciclovir 10-15 mg/kg three times daily is recommended, with dose adjustment for renal impairment 2
• For immunocompromised patients with HSV encephalitis, extend treatment to at least 21 days and perform repeat CSF PCR to confirm viral clearance 2

For Suspected Bacterial Etiology:

• Ampicillin is the treatment of choice for Listeria rhombencephalitis, the most common bacterial cause 1
• Antimicrobial therapy should be initiated as soon as possible after the diagnosis is considered likely, as bacterial meningitis/encephalitis is a neurological emergency 2

Adjunctive Therapy

• For VZV encephalitis with vasculitic component, consider adding a short course of corticosteroids (e.g., 60-80 mg of prednisolone daily for 3-5 days) 2
• For autoimmune or paraneoplastic causes of rhombencephalitis, immunosuppressive therapy with corticosteroids and either plasma exchange or IVIg may be beneficial 2
• Patients with falling level of consciousness require urgent ICU assessment for airway protection, ventilatory support, management of raised intracranial pressure, and optimization of cerebral perfusion 2

Specific Etiologies and Their Management

Listeria Rhombencephalitis:

• Most common infectious cause, primarily occurring in healthy young adults 1
• Presents with a biphasic course: flu-like syndrome followed by brainstem dysfunction 1
• Treatment is with ampicillin; duration should be based on clinical response 1

Viral Rhombencephalitis:

• HSV is the third most common infectious cause (after Listeria and Enterovirus 71) 1
• Mortality with aciclovir treatment is 22% versus 75% without aciclovir 1
• For VZV cerebellitis, antiviral treatments are not normally used as the disease is usually self-limiting 2

Autoimmune Rhombencephalitis:

• Behçet disease is the most common autoimmune etiology 1
• Treatment is with corticosteroids and immunosuppressive agents, but only 25% have complete recovery 1
• For NMDA receptor antibody-associated encephalitis, combination of corticosteroids with either plasma exchange or IVIg is recommended 2

Monitoring and Follow-up

• Repeat CSF PCR at the end of treatment course for HSV encephalitis to confirm clearance 2
• If CSF remains positive for HSV, continue aciclovir intravenously with weekly PCR until negative 2
• MRI is useful for follow-up examinations to assess treatment response 4
• Monitor renal function frequently when using aciclovir, as it can cause renal impairment through crystalluria in up to 20% of patients 2

Special Considerations

• In immunocompromised patients, consider a wider range of pathogens including CMV, EBV, toxoplasma, cryptococcus, and tuberculosis 2
• For immunocompromised children with VZV encephalitis, treatment duration may need to be longer than the standard 10 days 2
• Pediatric patients may present with atypical features such as bradycardia, requiring careful cardiac monitoring 5

Despite appropriate treatment, rhombencephalitis is associated with significant morbidity and mortality, making early diagnosis and prompt initiation of therapy crucial for improving outcomes 1, 6.