Management of Posterior Reversible Encephalopathy Syndrome (PRES)
The management of Posterior Reversible Encephalopathy Syndrome (PRES) requires immediate identification and removal of triggering factors, discontinuation of offending medications, and very stringent blood pressure control to prevent permanent neurological sequelae. 1
Etiology and Risk Factors
PRES is typically caused by:
- Severe hypertension/hypertensive emergency
- Immunosuppressive drugs
- Chemotherapy agents (particularly anti-angiogenic therapy)
- Autoimmune disorders
- Renal impairment
- Pre-eclampsia/eclampsia
Clinical Presentation
Common presenting features include:
- Acute neurological deficits
- Altered consciousness
- Visual disturbances or blindness
- Headaches
- Seizures
Diagnostic Evaluation
- MRI is the gold standard diagnostic tool
- Typical findings: T2-weighted hyperintensities indicating vasogenic edema
- Predominantly affects bilateral parieto-occipital lobes
- White matter more affected than gray matter
Management Algorithm
1. Immediate Interventions
- Identify and remove triggering factors
- Discontinue offending medications (immunosuppressants, chemotherapy)
- Control hypertension
- Target: Gradual blood pressure reduction to avoid cerebral hypoperfusion
- IV antihypertensives for severe hypertension
- Keep systolic blood pressure below 140 mmHg 2
2. Seizure Management
- Administer antiepileptic treatment for active seizures
- Consider prophylactic anticonvulsants in high-risk patients
- Benzodiazepines for acute seizure control
3. Specific Interventions Based on Etiology
- For eclampsia: Immediate delivery to remove triggering factor 3
- For medication-induced PRES: Change or discontinue the offending agent
- Example: Switching from mycophenolate mofetil to everolimus in transplant patients 2
- For autoimmune disease-related PRES: Address underlying autoimmune condition 4
4. Supportive Care
- Vigilant supportive care with aspiration precautions and IV hydration 5
- Elevation of the head to decrease hydrostatic pressure and cerebral edema
- Avoid medications that cause CNS depression
- Neurology consultation for ongoing management
Monitoring and Follow-up
- Frequent neurological evaluations to assess improvement
- Follow-up neuroimaging (MRI preferred) to confirm resolution
- Typical resolution occurs within 2 weeks with appropriate management 1
- Monitor for potential complications such as intracerebral hemorrhage
Prognosis
PRES is typically reversible with appropriate management, with neurological symptoms returning to normal within 48 hours and neuroradiological findings normalizing within 2 weeks 2. However, delayed diagnosis and treatment may lead to permanent neurological sequelae.
Poor Prognostic Factors
- Altered sensorium
- Extensive cerebral edema
- Presence of hemorrhage on imaging
- Delayed control of causative factors
Important Considerations
- Early diagnosis is crucial to prevent irreversible neurological sequelae
- The decision to reintroduce prior anticancer therapy must be carefully considered in cases of chemotherapy-induced PRES
- PRES can occur even in patients without hypertension, though this is less common 6
- Regular monitoring of patients on immunosuppressive therapy is important for early detection