What is the management of Posterior Reversible Encephalopathy Syndrome (PRES)?

Management of Posterior Reversible Encephalopathy Syndrome (PRES)

Immediately discontinue any offending agent (immunosuppressants, chemotherapy, or other triggering medications) and implement stringent blood pressure control with gradual reduction to avoid cerebral hypoperfusion—these are the two cornerstone interventions that determine whether PRES remains reversible or progresses to permanent neurological damage. 1, 2

Immediate Actions (First Hours)

Step 1: Identify and Remove Triggers

• Stop the causative agent immediately if PRES is associated with anticancer therapy, immunosuppressants (particularly cyclosporine), infliximab, or other medications 1, 3
• Common triggers include pre-existing hypertension, renal impairment, autoimmune diseases, high-dose chemotherapy, stem-cell or solid organ transplantation, and immunosuppression 1
• For ifosfamide-induced encephalopathy specifically, administer thiamine 100 mg IV every 8 hours (resolves symptoms within 10-30 hours) or methylene blue 50 mg IV every 4-6 hours as alternative 3

Step 2: Blood Pressure Management

• Implement very stringent blood pressure control with gradual reduction—this is the primary therapeutic intervention 1, 2, 4
• Target gradual reduction to avoid cerebral hypoperfusion, particularly when blood pressure is markedly elevated and cerebral autoregulation has failed 1
• Monitor blood pressure frequently during the acute phase to maintain safe range 1
• In hemodialysis patients, strict volume control may be a key element for both treatment and prevention 5

Step 3: Seizure Management

• Administer antiepileptic treatment for patients who develop seizures 1, 4
• Consider prophylactic anticonvulsants in high-risk patients with significant neurological deficits 1
• Use benzodiazepines for symptomatic treatment of acute seizures or status epilepticus 1, 3
• Status epilepticus is a typical presentation that requires immediate intervention 4, 6

Step 4: Supportive Care

• Implement aspiration precautions and intravenous hydration for patients with altered consciousness 1
• Avoid medications that cause CNS depression in patients with encephalopathy 1
• Maintain airway protection and consider ICU transfer for Grade III-IV encephalopathy (severe somnolence, coma, or seizures) 3
• Correct electrolyte imbalances (particularly hyponatremia) and monitor renal function 1, 3

Diagnostic Confirmation

Imaging Requirements

• MRI is the gold standard, showing increased signal intensity on T2-weighted or FLAIR imaging in bilateral parietal-occipital lobes, predominantly affecting white matter 1, 2
• The characteristic finding is vasogenic edema in posterior brain regions without infarction 2, 4
• CT scan can be useful to exclude intracranial hemorrhage when MRI is not immediately feasible 1
• Obtain brain MRI with DWI, T2 FLAIR, and T2* GRE or SWI sequences 7

Laboratory Workup

• Blood tests for electrolytes, glucose, calcium, complete blood count, inflammatory markers, blood urea, and creatinine 1, 7
• Review medication history, particularly immunosuppressants, chemotherapy, and recent drug changes 7
• Document blood pressure history and monitor for hypertension 7

Monitoring During Recovery

• Obtain neurological assessments every 4-6 hours until complete resolution 3
• Most patients recover completely within 3-5 days without neurological sequelae when promptly treated 3, 2
• Complete spontaneous remission occurs in most cases without sequelae, but early detection and management are key factors for rapid recovery 1
• Follow-up imaging should document resolution of vasogenic edema 2

Special Clinical Contexts

Immunotherapy-Associated PRES

• Follow Society for Immunotherapy of Cancer guidelines for immune-related adverse events 1
• Neurological consultation is recommended for acute neurological changes during ECMO 1

Perioperative PRES

• Consider PRES in differential diagnosis for delayed emergence from anesthesia 8
• Anesthesiologists should be vigilant during perioperative period, particularly with elevated mean arterial pressures 6, 8

Critical Pitfalls to Avoid

• Failure to discontinue the triggering agent leads to prolonged illness and increased risk of irreversible complications 1, 2
• Delayed diagnosis and treatment may result in death or irreversible neurological sequelae 4
• Missing concomitant conditions such as sepsis or metabolic disturbances complicates management 1
• Overly aggressive blood pressure reduction can cause cerebral hypoperfusion—reduction must be gradual 1, 2
• The reversibility of clinical and radiologic abnormalities is contingent on prompt blood pressure control and/or discontinuing the offending drug 2