Abstracts

Rationale: Posterior Reversible Encephalopathy Syndrome (PRES) is a syndrome characterized by increased signal intensity on T2-weighted and FLAIR MRI images, predominantly in the posterior quadrants of the cerebral hemispheres. It is most often associated with hypertensive crisis, eclampsia, chronic renal failure, and immunosuppression. Information pertaining to status epilepticus (SE) and PRES is lacking in the medical literature. A review of the literature demonstrates that it is not uncommon for patients to develop seizures in association with PRES, but only one article mentions SE in this population. Thus, the incidence of the co-existence of SE and PRES is unknown.Methods: We report two patients who developed PRES and nonconvulsive SE (NCSE) within a single week at our institution. A thorough review of these patients’ charts (paper and electronic), electroencephalograms (EEG) (continuous and routine), and all neuroimaging was undertaken.Results: Case 1: 41-year old African American female with a history of sickle cell disease, renal failure and seizure disorder presented to the hospital with intractable nausea and vomiting and uncontrolled hypertension (275/132 mmHg). Within 24 hours of admission, the patient became obtunded and unresponsive to external stimuli. EEG revealed high amplitude spike and slow wave activity in the right posterior temporal region, which was followed by rhythmic, medium to high amplitude, 3-4 Hz spike and slow waves in the right hemisphere with spread to the left hemisphere. This continued for 18 days despite medical treatment with midazolam, propofol, phenytoin, valproate and levetiracetam. MRI confirmed PRES and demonstrated improvement in T2 signal abnormality 20 days after the initial scan. Case 2: 62-year old African American female with a history of myocardial infarction, congestive heart failure and peripheral vascular disease presented to the hospital with headache and arm pain. The patient had uncontrolled hypertension on presentation with readings as high as 262/135 mmHg. Intubation was required for respiratory failure and declining mental status. EEG demonstrated continuous spike and wave and polyspike and wave discharges that were seen diffusely over both hemispheres. Electrographic seizures were seen between periods of burst suppression until the patient expired 7 days after onset. MRI revealed multiple areas of increased signal intensity on T2-weighted images within the periventricular, subcortical and deep white matter. Conclusions: Two consecutive cases of PRES associated with NCSE are presented. One patient returned to prior functional status while the second expired from medical complications. The constellation of PRES and NCSE has not been described in the literature and this leads to important questions such as the incidence of NCSE in patients with PRES, the character and quality of seizures, and the type of management required when these two conditions are found together. Further research needs to answer these questions.