Management of Posterior Reversible Encephalopathy Syndrome (PRES)

Clinical Presentation and Diagnosis

• PRES presents with acute neurological deficits including altered consciousness, visual disturbances, headaches, and seizures in patients with various underlying conditions, such as cancer or autoimmune diseases 1, 2
• Diagnosis is confirmed by T2-weighted MRI showing hyperintensities in bilateral parietal-occipital lobes, predominantly affecting white matter, which is a characteristic finding in PRES patients 3
• The pathophysiology involves disruption of the blood-brain barrier due to endothelial injury from abrupt blood pressure changes, leading to vasogenic edema, which is a key factor in the development of PRES 4

Management Algorithm

Step 1: Identify and Address Underlying Causes

• Discontinue the offending agent immediately, such as anticancer therapy or immunosuppressants, to prevent further endothelial injury and progression of PRES 1, 2
• Common triggers include pre-existing arterial hypertension, renal impairment, autoimmune diseases, high-dose antineoplastic therapy, allogenic stem-cell transplantation, solid organ transplantation, and immunosuppression, particularly with cyclosporine 1, 3, 4, 2

Step 2: Blood Pressure Management

• Implement very stringent blood pressure control as the cornerstone of management, with a target of gradual reduction of blood pressure to avoid cerebral hypoperfusion, which is crucial for preventing further brain injury 1, 3, 4
• Monitor blood pressure frequently during the acute phase to ensure that it remains within a safe range and to prevent complications 2

Step 3: Seizure Management

• Administer antiepileptic treatment for patients who develop seizures, and consider prophylactic anticonvulsants in high-risk patients with significant neurological deficits, to prevent further brain injury and improve outcomes 1, 4, 2
• Benzodiazepines may be used for symptomatic treatment of acute seizures, but their use should be carefully monitored to avoid adverse effects 3

Step 4: Electrolyte Management

• Correct electrolyte imbalances if present, and monitor renal function, especially in patients with pre-existing renal impairment, to prevent further complications 1, 4

Special Considerations

• For PRES associated with immunotherapy, follow the Society for Immunotherapy of Cancer guidelines for immune-related adverse events, which provide recommendations for the management of immune-related adverse events, including PRES 5
• In cases with persistent symptoms, consider alternative diagnoses or complications, and consult with relevant specialists, such as neurologists or otolaryngologists, to ensure that all possible causes are considered 6
• For PRES during ECMO, neurological consultation is recommended for acute neurological changes, to ensure that patients receive timely and appropriate care 7

Prognosis

• Complete spontaneous remission occurs in most cases without sequelae, but early detection and management are key factors for rapid recovery and good outcomes, highlighting the importance of prompt recognition and treatment of PRES 1

Common Pitfalls to Avoid

• Failure to identify and discontinue the triggering agent, such as anticancer therapy or immunosuppressants, can lead to prolonged illness and increased risk of complications, emphasizing the need for careful evaluation and management of patients with PRES 1, 4
• Missing concomitant conditions that may complicate management, such as sepsis or metabolic disturbances, can also lead to poor outcomes, highlighting the importance of comprehensive care for patients with PRES 3

Management of Posterior Reversible Encephalopathy Syndrome (PRES)

Diagnostic Imaging and Blood Pressure Management

• The European Society of Cardiology recommends implementing stringent blood pressure control as the primary therapeutic intervention, with gradual reduction to avoid cerebral hypoperfusion, especially when blood pressure is markedly elevated and cerebral autoregulation fails, leading to cerebral edema in posterior brain areas 8
• MRI is the gold standard for diagnosis, showing increased signal intensity on T2-weighted or fluid-attenuated inversion recovery (FLAIR) imaging in posterior brain regions, and CT scan can be useful to exclude intracranial hemorrhage when MRI is not feasible 8

Supportive Care

• The European Society of Medical Oncology suggests implementing aspiration precautions and intravenous hydration for patients with altered consciousness, and avoiding medications that cause CNS depression in patients with encephalopathy 9

Posterior Reversible Encephalopathy Syndrome Causes and Associations

Medication-Related Causes

• Infliximab, an anti-TNF therapy, has been reported to cause PRES in patients with Crohn's disease, highlighting the need for vigilance in patients receiving this medication 10

Management of Posterior Reversible Encephalopathy Syndrome (PRES)

Supportive Care Measures

• The American Society of Clinical Oncology recommends administering antiepileptic treatment for patients who develop seizures, with careful monitoring to avoid CNS depression, and consider prophylactic anticonvulsants in high-risk patients with significant neurological deficits to prevent further brain injury, using medications such as benzodiazepines, with a recommended dose of lorazepam 0.05 mg/kg, maximum 1 mg per dose IV every 8 hours, for symptomatic treatment 11
• Elevate the head of the bed to 30 degrees to help reduce intracranial pressure, implement aspiration precautions and intravenous hydration for patients with altered consciousness, and avoid medications that cause CNS depression in patients with encephalopathy, using low doses of lorazepam or haloperidol with careful monitoring 11
• Withhold oral intake and assess swallowing function, substituting all oral medications and nutrition with IV forms if swallowing is impaired, to prevent complications 11

Diagnostic Confirmation and Monitoring

• Obtain neurology consultation for comprehensive neurological assessment and management guidance, and consider additional diagnostic workup, including fundoscopic exam to assess for papilledema, EEG if seizures are suspected or to rule out non-convulsive status epilepticus, and lumbar puncture with opening pressure measurement if indicated, according to the Society for Neuro-Oncology guidelines 11

Posterior Reversible Encephalopathy Syndrome (PRES) Pathophysiology

Mechanisms and Associations

• The American Academy of Neurology suggests that reactivation of Varicella-Zoster Virus (VZV), especially in immunocompromised patients, can precipitate PRES even without significant hypertension 12
• The pathogenic process in VZV encephalitis is considered an immune-mediated reaction to low-level viral replication, rather than direct viral cytopathology 12

PRES in the Context of VZV Infection

• The Infectious Diseases Society of America notes that VZV infection causes direct endothelial dysfunction and disruption of the blood-brain barrier, which can be exacerbated by associated vasculopathy 12
• The combination of VZV infection, immunocompromised state, and vasculopathy creates a scenario of multiple insults to the cerebral endothelium, contributing to the development of PRES 12

Posterior Reversible Encephalopathy Syndrome (PRES) Diagnosis and Management

Imaging Characteristics

• The European Society of Cardiology recommends that CT scans be used to rule out intracranial hemorrhage, particularly in emergency settings where MRI is not immediately available 13, 14
• CT scans have limited sensitivity in detecting PRES, especially in the early stages, and may appear normal in up to 37% of confirmed cases 13, 14

Clinical Presentation and Diagnosis

• The European Heart Journal notes that PRES is characterized by acute neurological deficits, including decreased consciousness, seizures, visual disturbances, and headache, and that MRI with FLAIR sequences is more sensitive in detecting characteristic lesions than CT 13
• Patients may experience somnolence, lethargy, tonic-clonic seizures, and cortical blindness, which can progress to loss of consciousness 13

Optimal Imaging Recommendations

• The American College of Radiology suggests that MRI should be performed promptly if CT scans are normal but clinical symptoms suggest PRES, as MRI is the diagnostic modality of choice 14
• CT without contrast remains useful in emergency settings to rule out intracranial hemorrhage, especially if MRI is not immediately available 13, 14

Management and Treatment

• The European Heart Journal recommends that precipitating agents such as anticancer therapy, immunosuppressants, or vasoactive drugs be discontinued immediately to prevent further endothelial injury 13
• Strict blood pressure control is essential, with a gradual reduction in blood pressure to avoid cerebral hypoperfusion 13