Reversible Posterior Leukoencephalopathy Syndrome

• Reversible Posterior Leukoencephalopathy Syndrome (RPLES) is an acute neurological disorder affecting the brain’s posterior white matter.
• It is often triggered by severe hypertension, eclampsia, certain medications, or autoimmune diseases.
• Common symptoms include headache, seizures, visual disturbances, and altered mental status.
• Early diagnosis and management of the underlying cause are crucial for successful treatment and reversibility.
• With prompt intervention, most patients experience significant improvement or complete resolution of symptoms and brain changes.

What is Reversible Posterior Leukoencephalopathy Syndrome (RPLES)?

Reversible Posterior Leukoencephalopathy Syndrome (RPLES) is a complex neurological disorder characterized by a sudden onset of symptoms and specific findings on brain imaging, predominantly in the posterior (back) parts of the brain. This condition is also frequently referred to as Posterior Reversible Encephalopathy Syndrome (PRES). It is considered “reversible” because, with timely and appropriate treatment, the clinical symptoms and radiological abnormalities often resolve completely or significantly improve.

The syndrome involves a disruption of the blood-brain barrier, leading to vasogenic edema (fluid leakage from blood vessels) in the brain tissue. While the term “leukoencephalopathy” suggests involvement of white matter, gray matter can also be affected. The exact prevalence of RPLES is not precisely known, but it is increasingly recognized due to improved neuroimaging techniques. It can affect individuals of any age, though it is more common in adults, particularly those with predisposing medical conditions.

RPLES Symptoms and Causes

Understanding RPLES symptoms and causes is crucial for prompt diagnosis and intervention. The clinical presentation of RPLES can vary but typically involves a rapid onset of neurological symptoms. These symptoms often reflect the areas of the brain affected by edema.

Common symptoms include:

• Headache: Often severe and sudden.
• Seizures: Ranging from focal to generalized tonic-clonic seizures.
• Altered mental status: Confusion, lethargy, or even coma.
• Visual disturbances: Blurry vision, hemianopsia (loss of half of the visual field), or cortical blindness.
• Focal neurological deficits: Weakness or numbness in parts of the body, though less common.

The causes of RPLES are diverse but generally involve conditions that lead to endothelial dysfunction and a breakdown of the blood-brain barrier. The most frequent trigger is acute, severe hypertension, where a sudden spike in blood pressure overwhelms the brain’s autoregulatory capacity, leading to hyperperfusion and fluid extravasation. For example, severe hypertension, often defined as systolic blood pressure >160 mmHg or diastolic blood pressure >110 mmHg, is a common precipitating factor, notably in conditions like pre-eclampsia/eclampsia, which affects approximately 5-8% of pregnancies globally according to the World Health Organization (WHO).

Other significant causes include:

• Eclampsia and pre-eclampsia: Pregnancy-related hypertensive disorders.
• Immunosuppressive medications: Such as calcineurin inhibitors (e.g., cyclosporine, tacrolimus) used in organ transplantation.
• Chemotherapeutic agents: Certain drugs used in cancer treatment.
• Autoimmune diseases: Systemic lupus erythematosus, vasculitis.
• Kidney failure: Acute or chronic renal insufficiency.
• Sepsis and shock.

Reversible Posterior Leukoencephalopathy Syndrome Treatment

Effective Reversible Posterior Leukoencephalopathy Syndrome treatment focuses primarily on identifying and managing the underlying cause. Given the potentially reversible nature of the condition, prompt and aggressive intervention is key to preventing permanent neurological damage. The immediate goals of treatment are to control symptoms and reverse the physiological triggers.

Key aspects of treatment include:

1. Blood Pressure Control: For patients with hypertension-induced RPLES, careful and controlled reduction of blood pressure is paramount. Intravenous antihypertensive medications are often used to gradually lower blood pressure to a safe range, typically aiming for a 10-25% reduction within the first hour, followed by further stabilization.
2. Discontinuation of Offending Agents: If the syndrome is triggered by medications (e.g., immunosuppressants, chemotherapy), these agents should be discontinued or their dosages reduced under medical supervision, if clinically feasible.
3. Seizure Management: Antiepileptic drugs are administered to control seizures and prevent recurrence. This is a critical step, as recurrent seizures can exacerbate brain injury.
4. Management of Underlying Conditions: Treatment of other underlying causes, such as eclampsia, kidney failure, or autoimmune diseases, is essential for long-term recovery. This may involve magnesium sulfate for eclampsia or specific therapies for autoimmune conditions.

Patients with RPLES require close monitoring in a hospital setting, often in an intensive care unit, to manage symptoms and track neurological status. Brain imaging, typically MRI, is used to confirm the diagnosis and monitor the resolution of edema. With appropriate and timely management, the prognosis for most patients with RPLES is favorable, with many experiencing complete recovery of neurological function and resolution of brain imaging abnormalities within days to weeks.