Acronym for Posterior Reversible Encephalopathy Syndrome.

Rare. Clinico-radiological syndrome: transient acute encephalopathy the clinical signs of which are not specific but the MRI images of which are typical. Clinical signs: sudden onset hypertension, vomiting, disorders of consciousness, cortical blindness, convulsions. MRI:  focal, often asymmetric, areas of vasogenic edema of the white substance at the level of the parieto-occipital areas.

The main causes are:

-        high blood pressure, including a few cases of postoperative hypertension

-        chemotherapy: methotrexate, vincristine, L-asparaginase, cyclophosphamide, cytarabine, bevacizumab, cis-platinum

-        kidney disease: hemolytic uremic syndrome, Henoch-Schonlein purpura, acute glomerulonephritis

-        immunosuppressive drugs: corticosteroids, cyclosporine, tacrolimus, mofetyl mycofenolate

-        hypomagnesemia, hypo - or hypercalcemia

-        eclampsia

-        vasculitis, systemic lupus erythematosus.

It seems to be a sort of vasoregulation angiopathy with disruption of the blood-brain barrier : posterior areas of the brain are more affected as the sympathetic innervation is less developed at the vertebro-basilar level. Normally, the clinical signs are reversible in a few days or weeks following the treatment of hypertension and/or the cause, but the MRI anomalies may persist longer. However, there may be sequellae in case of focal hemorrhages.

Anesthetic implications:

high blood pressure, disorders of consciousness, risk of seizures and cerebral hemorrhage. To be Kept in mind in case of loss of vision at the awakening of anesthesia.

References : 

-        Incecik F, Hergüner MO, Altumbasak S et al. 
Posterior reversible encephalopathy syndrome in the pediatric population. 
Pediatr Nephrol 2007; 22: 1921-9.

-        Gamie Z, Rizuran A, Balen FG, Clarke M, Hassoon MM. 
Posterior reversible encephalopathy syndrome in a child with cyclical vomiting and hypertension: a case report. 
J Medical Case Reports 2011; 5:137

-        Vandeponseele M, Brichard B, Dupont S, Fylaktopoulou V, Sauvage A. 
Le syndrome d’encéphalopathie postérieure réversible (PRES) : une pathologie méconnue en pédiatrie. 
Louvain médical  2014 ; 133 : 49-54.

-         Inoue S, Kawaguchi M, Furuya H. 
A case of posterior reversible encephalopathy syndrome after emergence from anesthesia. 
J Anesth 2012; 26: 111-4 

-        Gallop L, McNeillis N.
Posterior reversible encephalopathy syndrome in a child, following splenectomy under combined general and spinal anaesthesia.
Anaesthesia Reports 2023, 11, e12245 doi:10.1002/anr3.12245

Updated: October 2023