What is the treatment for posterior reversible encephalopathy syndrome (PRES)?

Treatment of Posterior Reversible Encephalopathy Syndrome (PRES)

The cornerstone of PRES management is immediate identification and discontinuation of the triggering agent combined with stringent blood pressure control, which leads to complete spontaneous remission in most cases without sequelae. 1

Step 1: Identify and Remove the Trigger

Immediately discontinue any offending medications or therapies that may have precipitated PRES, as failure to do so can lead to prolonged illness and increased risk of complications. 1

Common triggers requiring immediate cessation include:

• Immunosuppressants (particularly cyclosporine) 1
• High-dose antineoplastic therapy 1
• Anti-TNF therapy such as infliximab 1
• Any recently initiated chemotherapy agents 1

Underlying conditions to address:

• Pre-existing arterial hypertension 1
• Renal impairment 1
• Autoimmune disease flares 1
• Post-transplantation status (solid organ or stem cell) 1

Step 2: Blood Pressure Management

Implement very stringent blood pressure control with gradual reduction to avoid cerebral hypoperfusion, which is the primary therapeutic intervention recommended by the European Society of Cardiology. 1

Key principles:

• Target gradual blood pressure reduction rather than rapid normalization to prevent cerebral hypoperfusion 1
• Monitor blood pressure frequently during the acute phase 1
• Use intravenous antihypertensives such as labetalol or nitroprusside for severe hypertension 2
• Avoid overly aggressive reduction that could worsen cerebral perfusion 1

Step 3: Seizure Management

Administer antiepileptic treatment for any patient who develops seizures, as seizures are a common presenting feature and require prompt control. 1

Specific recommendations:

• Use benzodiazepines for acute seizure control: lorazepam 0.05 mg/kg (maximum 1 mg per dose) IV every 8 hours 1
• Consider prophylactic anticonvulsants in high-risk patients with significant neurological deficits 1
• Phenytoin is an alternative option for seizure control 2
• Monitor carefully to avoid CNS depression 1

Step 4: Supportive Care Measures

Elevate the head of the bed to 30 degrees to help reduce intracranial pressure. 1, 3

Additional supportive measures:

• Implement aspiration precautions and intravenous hydration for patients with altered consciousness 1
• Withhold oral intake and assess swallowing function, substituting all oral medications and nutrition with IV forms if swallowing is impaired 1
• Avoid medications that cause CNS depression in patients with encephalopathy 1
• Use low doses of lorazepam or haloperidol only if absolutely necessary for unmanageable agitation, with careful monitoring 1, 3
• Administer anti-edema therapy with mannitol (20%, 60 mL every 3 hours) if significant cerebral edema is present 2

Step 5: Correct Electrolyte Imbalances

Monitor and correct any electrolyte abnormalities, particularly in patients with pre-existing renal impairment. 1

Essential monitoring:

• Check glucose, potassium, magnesium, phosphate, and calcium levels 3
• Monitor renal function closely 1
• Correct imbalances promptly to prevent further complications 1

Step 6: Diagnostic Confirmation and Monitoring

Obtain urgent neurology consultation for comprehensive neurological assessment and management guidance. 1

Diagnostic workup:

• Brain MRI is the gold standard, showing T2-weighted or FLAIR hyperintensities in bilateral parietal-occipital lobes 1, 4
• CT scan can be useful to exclude intracranial hemorrhage when MRI is not immediately available 1
• Consider fundoscopic exam to assess for papilledema 1
• Obtain EEG if seizures are suspected or to rule out non-convulsive status epilepticus 1
• Lumbar puncture with opening pressure measurement may be indicated to exclude alternative diagnoses 1

Special Considerations

For PRES associated with immunotherapy, follow the Society for Immunotherapy of Cancer guidelines for immune-related adverse events. 1

In eclampsia-related PRES, consider induction of vaginal delivery as part of definitive management. 2

For patients on ECMO with PRES, neurological consultation is recommended for acute neurological changes. 1

Airway Protection for Severe Cases

For Grade III-IV encephalopathy with declining level of consciousness, intubate for airway protection and consider propofol for sedation in small doses. 3

Urgent ICU assessment is required for:

• Declining level of consciousness 3
• Need for airway protection and ventilatory support 3
• Inability to protect airway 3

Common Pitfalls to Avoid

Failure to identify and discontinue the triggering agent is the most critical error, leading to prolonged illness and increased risk of permanent neurological damage. 1

Other pitfalls:

• Missing concomitant conditions such as sepsis or metabolic disturbances that may complicate management 1
• Overly aggressive blood pressure reduction causing cerebral hypoperfusion 1
• Delayed neuroimaging leading to missed diagnosis 5, 6
• Using excessive sedation that masks neurological deterioration 1, 3

Prognosis

Complete spontaneous remission occurs in most cases without sequelae when early detection and appropriate management are implemented, though delayed recognition and treatment can result in death, irreversible neurological deficit, or chronic epilepsy. 1, 5 Normalization of clinical findings typically occurs within 7 days, though radiological abnormalities may take longer to resolve. 2