Posterior reversible encephalopathy syndrome, also known as reversible posterior leukoencephalopathy
syndrome, 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. On magnetic resonance imaging of the brain, areas of edema are seen.
The symptoms tend to resolve after a period of time, although visual changes sometimes
remain. It was first described in 1996.
Causes Several factors appear to play a role in the
pathogenesis of PRES, including immunosuppressive therapy, renal failure, eclampsia, severe
high blood pressure, and lupus. Low magnesium levels can augment PRES.
Signs and symptoms Typical symptoms of PRES include headache,
nausea, vomiting, altered mental status, seizures, stupor, and visual disturbances. Focal neurologic
signs are uncommon in PRES. Diagnosis
The diagnosis is typically made clinically, with supportive findings on magnetic resonance
imaging of the brain; this may show hyperintensities on T2-weighed imaging. Three different patterns
have been described on MRI imaging. Cerebral angiography may provide a more definite diagnosis.
Treatment The treatment of PRES depends on the underlying
cause. For instance, if the main problem is high blood pressure, blood pressure control
will accelerate the resolution of the abnormalities. If the likely cause is medication, the withdrawal
of the drug in question is needed. Prognosis
Many cases resolve within 1–2 weeks of controlling the blood pressure and eliminating the enciting
factor. However, long-lasting or even permanent neurologic dysfunction may remain. Though
uncommon, death may occur with progressive swelling of the brain or a bleed in the brain.
Epidemiology The incidence of PRES is not currently known.
Case reports suggest that there is no age predilection, with cases reported in people
ages 2 to 90 years old. It may be somewhat more common in females.
See also Leukoencephalopathy
References ^ Garg RK. "Posterior leukoencephalopathy
syndrome". Postgrad Med J 77: 24–8. doi:10.1136/pmj.77.903.24. PMC 1741870. PMID 11123390.
^ Pula JH, Eggenberger E. "Posterior reversible encephalopathy syndrome". Curr Opin Ophthalmol
19: 479–84. doi:10.1097/ICU.0b013e3283129746. PMID 18854692.
^ Hinchey J, Chaves C, Appignani B, Breen J, Pao L, Wang A, Pessin M, Lamy C, Mas J,
Caplan L. "A reversible posterior leukoencephalopathy syndrome.". N Engl J Med 334: 494–500. doi:10.1056/NEJM199602223340803.
PMID 8559202. ^ a b c Rajasekhar, A.; George, T. J.. "Gemcitabine-Induced
Reversible Posterior Leukoencephalopathy Syndrome: A Case Report and Review of the Literature".
The Oncologist 12: 1332–1335. doi:10.1634/theoncologist.12-11-1332. PMID 18055853.
^ Kur, JK; Esdaile, JM. "Posterior reversible encephalopathy syndrome--an underrecognized
manifestation of systemic lupus erythematosus.". The Journal of rheumatology 33: 2178–83.
PMID 16960925. ^ Peter P, George A. Posterior reversible
encephalopathy syndrome and the pediatric population. J Pediatr Neurosci 2012;7:136-8.
^ Pedraza, R; Marik PE; Varon J. "Posterior Reversible Encephalopathy Syndrome: A Review".
Critical Care and Shock 12: 135–143.