The CT scan of her head was unremarkable, and this was followed by a lumbar puncture that showed cerebrospinal fluid glucose 101 mg/dL, elevated protein 75.4 mg/dL, and a leukocyte count of 14/cumm. Given her confusion, septic presentation and seizure, she was treated for possible meningoencephalitis with intravenous vancomycin, cetriaxone, ampicillin, acyclovir, and dexamethasone. She received intravenous metoprolol, followed by oral amlodipine and lisinopril to control hypertension. An EEG was unremarkable, followed by a brain MRI that showed curvilinear high intensity signals on T2 flair in bilateral parietal, occipital and temporal lobes. This indicated the presence of edema, and was consistent with Posterior Reversible Encephalopathy Syndrome. CSF culture eventually was negative, and judicious BP control helped resolve her mental status changes. She was sent home on antihypertensive and anti-seizure medications, to follow up with neurology and a repeat MRI in 3 months.
Discussion: Posterior Reversible Encephalopathy Syndrome (PRES) is characterized by posterior cerebral white matter edema due to hypertension, which is beyond the physiologic limits of cerebral auto-regulation. Other postulated theories include reactive cerebral ischemia, and endothelial dysfunction. Seizures are often the initial presentation, with generalized tonic-clonic seizures progressing to status epilepticus being the most common. CSF protein is typically high in patients with PRES and proportionate to the extent of edema, MRI still being key to the diagnosis. The limited data on PRES confines treatment recommendations, however lowering blood pressure has been shown to dramatically improve symptoms.
Conclusions: Headache, confusion, and seizures in patients with severe hypertension, along with image findings on MRI should raise suspicion for PRES. Prompt treatment with anti-hypertensives can improve symptoms, and prevent permanent brain damage from a condition otherwise reversible.