The posterior circulation may be particularly susceptible to these changes, owing to the relative paucity of sympathetic innervation in the posterior fossa. , With prompt recognition and treatment of PRES, many patients will recover fully, though persistent neurologic deficits can occur in 10-44%, with delay in initiation of treatment associated with unfavorable outcomes. The patient is admitted, and the following morning, the patient undergoes an MRI/MRA of her brain, which demonstrates hyperintense signal on T2 and FLAIR sequences localized to the bilateral parietal and occipital lobes, concerning for posterior reversible encephalopathy syndrome (PRES), or also known as reversible posterior leukoencephalopathy syndrome (RIPLS). , There is no direct treatment for PRES, other than removing or treating any underlying cause.  Some patterns on electroencephalography (EEG) are also associated with a poorer outcome. Extraocular movements are intact.  In children this is more common still, at 90%.  After a hematopoietic stem cell transplantation (bone marrow transplant) the risk of PRES is approximately 8%, whereas the risk is lower (0.4-6%) after a solid organ transplant. Garg, R.K., N. Kumar, and H.S. The diagnosis is usually made by brain scan (MRI) on which areas of swelling can be identified. Seizures are often the presenting symptom and occur in a majority of patients. and A.A. Rabinstein, Posterior reversible encephalopathy syndrome: clinical and radiological manifestations, pathophysiology, and outstanding questions. , Multiple comorbid conditions are associated with PRES, including hypertension, renal disease, organ transplantation, autoimmune disease, preeclampsia/eclampsia, malignancy, sepsis immunosuppressive therapy and cytotoxic medications (Table 1).  In PRES secondary to pre-eclampsia, magnesium sulfate may be administered. Clinical features of PRES are summarized in Table 2. There has been no recent trauma, toxic exposure, or infectious symptoms. Pupils are 3 mm, equal, and sluggishly reactive. Notify me of follow-up comments by email. emDOCs subscribes to the Free Open Access Meducation. This predominantly affects the "posterior" parts of the brain which is more susceptible. The appearance of name-brand products in this article does not constitute endorsement by Brooke Army Medical Center, the U.S. Army Medical Department, the U.S. Army Office of the Surgeon General, the Department of the Army, the Department of the Air Force, or the Department of Defense, or the U.S. Government of the information, products, or services contained therein. AJNR 29. , Seizures occur in about two thirds of cases. A 45-year-old female presents to the emergency department (ED) with 3 days of progressively worsening headache, confusion, and vision changes. Neurol India, 2018. If prior records are available, a comparison of prior blood pressure readings can provide helpful information in identifying an acute change from baseline values. Her cardiovascular and pulmonary exams are unremarkable. She is awake but confused. ED management of PRES involves management and prevention of seizures and management of blood pressure, though there exist no randomized trials to define the efficacy of specific treatment modalities. Seizures are treated in the same manner as in other disorders, with benzodiazepines as first-line agents. Brewer, J., et al., Posterior reversible encephalopathy syndrome in 46 of 47 patients with eclampsia.  A number of other associations have also been reported, including some other groups of medications, blood transfusion, elevated calcium levels, decreased magnesium levels, postpartum cerebral angiopathy, and drugs of abuse (cocaine and amphetamine). 63(6): p. 983-9. , normal capability of blood vessels in the brain, reversible cerebral vasoconstriction syndrome, "Posterior reversible encephalopathy syndrome", https://en.wikipedia.org/w/index.php?title=Posterior_reversible_encephalopathy_syndrome&oldid=983005445, Creative Commons Attribution-ShareAlike License, Reversible posterior leukoencephalopathy syndrome (RPLS), Posterior reversible encephalopathy syndrome visible on, Seizures, headache, visual disturbances, altered mental state, sometimes limb weakness or inability to speak, This page was last edited on 11 October 2020, at 17:50. Computed tomography (CT) of the head without contrast reveals hypoattenuation in the subcortical white matter of the parietal and occipital lobes. 66(5): p. 1316-1323. 14(9): p. 914-925. Thompson, R.J., et al., Posterior reversible encephalopathy syndrome in the emergency department: case series and literature review. She has no external signs of trauma. , If there is a hypertensive emergency, the blood pressure is lowered by 20-30% using continuous infusion of a blood pressure lowering drug with close monitoring. PRES is perhaps the most widely recognized name for this syndrome, but it has also been called reversible posterior leukoencephalopathy syndrome (RPLS) and a handful of less commonly used names. Posterior reversible encephalopathy syndrome (PRES) is a syndrome characterized by headache, confusion, seizures and visual loss.It may occur due to a number of causes, predominantly malignant hypertension, eclampsia and some medical treatments. Reversible posterior leukoencephalopathy syndrome (RPLS) is a clinical radiographic syndrome of heterogeneous etiologies that are grouped together because of similar findings on neuroimaging studies.  People with diabetes may have a worse outcome, and abnormalities in the corpus callosum on MRI have been linked with worse prognosis.  It is also called the "breakthrough" theory, or the "hyperperfusion theory". The "cytotoxic" theory suggests that it is direct cell damage by toxins (usually medications) that precipitates the edema. The patient does not have a known history of mental illness. Your email address will not be published. Dhar, R., Neurologic Complications of Transplantation.  Computed tomography scanning may be performed in the first instance; this may show low density white matter areas in the posterior lobes. PRES may be complicated by intracranial hemorrhage, but this is relatively rare. The "immunogenic" theory suggests a role for the immune system (specifically T cells).  Of those who have residual symptoms after PRES, this is attributable largely to hemorrhage. The differential diagnosis for patients with PRES is broad and many emergent etiologies must be considered. Curr Opin Neurol, 2019. , The diagnosis is typically made with magnetic resonance imaging of the brain. 49(10): p. 1793-1800. The patient has a past medical history notable for systemic lupus erythematosus (SLE), lupus nephritis, and hypertension. However, 30% of patients may present without significantly elevated (or normal) blood pressure, and accordingly, the generalizability of the hyperperfusion theory is contested.  Some consider that the abnormalities need to be shown to be reversible. The excessive pressure damages the endothelial layer and the blood-brain barrier, leading to swelling (edema). , In 10–25% of cases of PRES there is evidence of hemorrhage on neuroimaging. [16-18] PRES is also well-described in pediatric patients, and risk factors, clinical features, and radiographic findings are similar to those seen in adults. Mayo Clinic proceedings, 2011.  If the appearances are not typical, other causes for the symptoms and the imaging abnormalities need to considered before PRES can be diagnosed conclusively. [5-7] , PRES is associated with a number of conditions, including hypertension, renal disease, preeclampsia, autoimmune disease, and use of immunomodulatory medications. Would you like to contribute? The rest of the laboratory results are normal, including VBG and electrolytes. [8, 22] MRI is imaging modality most likely to identify abnormalities consistent with PRES, though there is no true gold standard. 28(1): p. 4-11. 1043-1049.  40% of all people with PRES are unwell enough to require intensive care unit admission for close observation and treatment of complications. PRES was first described in 1996. Posterior reversible encephalopathy syndrome (PRES) is a clinico-radiological syndrome characterized by symptoms including a headache, seizures, altered consciousness and visual disturbances [ 1 ]. 16(1): p. 5-10.  Some consider the cytotoxic and immunogenic theories together as a single "toxic" theory.