Management of Posterior Reversible Encephalopathy Syndrome (PRES)
The management of PRES requires immediate discontinuation of the triggering agent, very stringent blood pressure control, and antiepileptic treatment for seizures, with most cases resolving within 2 weeks with appropriate supportive care. 1
Clinical Presentation and Diagnosis
PRES presents with:
- Acute neurological deficits
- Altered consciousness
- Visual disturbances (including blindness)
- Headaches
- Seizures
Diagnosis is confirmed by:
- Clinical presentation
- T2-weighted MRI showing hyperintensities in bilateral parietal-occipital lobes, predominantly in white matter
- Exclusion of other causes of encephalopathy
Pathophysiology and Risk Factors
PRES results from disruption of the blood-brain barrier due to endothelial injury caused by abrupt blood pressure changes, leading to vasogenic edema 1. Key risk factors include:
- Pre-existing arterial hypertension
- Renal impairment
- Autoimmune diseases
- High-dose antineoplastic therapy
- Allogenic stem-cell transplantation
- Solid organ transplantation
- Immunosuppression (e.g., ciclosporin)
- Eclampsia
- Cancer chemotherapy
Management Algorithm
Step 1: Immediate Interventions
- Discontinue the triggering agent (e.g., anticancer therapy, immunosuppressants) 1
- Control blood pressure very stringently 1
- Target: Gradual reduction to avoid cerebral hypoperfusion
- Use IV antihypertensives in severe cases
Step 2: Symptomatic Management
- Treat seizures with antiepileptic medications 1
- Benzodiazepines for acute seizure control
- Consider short-term antiepileptic drugs if recurrent seizures
- Correct electrolyte imbalances if present 1
Step 3: Supportive Care
- Monitor neurological status closely
- Provide appropriate ICU care if severe symptoms
- Address any underlying conditions (e.g., renal dysfunction, autoimmune disorders)
Step 4: Follow-up
- Most cases resolve within 2 weeks with appropriate management 1
- Follow-up MRI to confirm resolution of vasogenic edema
- Decision regarding reintroduction of prior anticancer therapy should be made on an individual basis 1
Special Considerations
Immunotherapy-Related PRES
For PRES associated with immune checkpoint inhibitors:
- Permanently discontinue the immunotherapy for grade 3-4 events 1
- Consider IV corticosteroids (1-2 mg/kg/day methylprednisolone equivalents) for severe cases 1
- Consider plasmapheresis if no improvement after 3 days of corticosteroid treatment 1
Hypertensive Emergency with PRES
When PRES occurs in the setting of hypertensive emergency:
- Careful blood pressure reduction is crucial to prevent further endothelial injury 1
- MRI with FLAIR imaging is valuable to confirm diagnosis and monitor response 1
Prognosis and Outcomes
With prompt recognition and appropriate management:
- Most patients experience complete clinical and radiological recovery
- PRES is typically reversible with supportive management within 2 weeks 1
- Some patients may have residual neurological deficits if treatment is delayed
Pitfalls and Caveats
Delayed diagnosis: PRES can mimic other neurological conditions; maintain high index of suspicion in at-risk patients with acute neurological symptoms.
Overly aggressive BP reduction: Too rapid reduction in blood pressure can lead to cerebral hypoperfusion and ischemia.
Incomplete workup: Always exclude other causes of encephalopathy (stroke, infection, metabolic disorders).
Failure to remove the triggering agent: Continued exposure to the causative agent may lead to irreversible neurological damage.
Inadequate follow-up: Some patients may develop recurrent PRES or have incomplete resolution of symptoms.