Case Presentation: A 60-year-old female with history of hypertension, rheumatoid arthritis on Adalimumab, and end stage renal disease (ESRD) due to lupus nephritis for which she was recently started on mycophenolate and high dose steroids, presented with 2-3 hour history of sudden onset severe occipital headache, followed by vomiting episodes and complete loss of vision. She had no speech, swallowing or hearing impairments. There was no neck stiffness or unilateral weakness. Vital signs on presentation were significant for blood pressure of 205/104. Neurological examination was unremarkable except for visual acuity of perception of light and mild tremors in extremities. She had ulnar deviation of the fingers bilaterally, but remainder of physical examination was also unremarkable. Laboratory work up was only significant for electrolyte changes consistent with ESRD. Computed Tomography (CT) scan of the head showed bilateral symmetric vasogenic edema involving the occipital lobes and portion of the parietal lobes, typical of posterior reversible leukoencephalopathy syndrome (PRES). She was started on scheduled oral hydralazine, and as needed intravenous Hydralazine for blood pressure beyond a specified range. Oral Metoprolol and Amlodipine were also resumed. Dose of Mycophenolate was reduced, while Adalimumab was placed on hold. She was also started on intravenous Fosphenytoin for seizure prophylaxis. Headache and vomiting resolved with improvement in blood pressure, and vision returned to normal over 1-2 days. She was discharged home in stable health without further complications.
Discussion: PRES is a neurologic syndrome characterized by radiologic features of the brain and clinical features that include headache, confusion, visual symptoms and seizures. Typical radiologic findings are consistent with vasogenic edema and are predominantly localized to the posterior cerebral hemispheres. Diffusion weighted imaging can help differentiate PRES from stroke. PRES occurs most often in hypertensive crisis, preeclampsia or with cytotoxic immunosuppressive therapy. Treatment involves blood pressure control and discontinuation or reduction in dose of offending cytotoxic agent. Patients who have a seizure are treated with antiepileptics, but this can be discontinued after symptoms and neuroimaging findings resolve as risk of late recurrence of seizure or epilepsy in uncomplicated PRES is low.
Conclusions: PRES should be considered in differential diagnosis of visual loss and is remarkable for mostly being completely reversible with treatment. It can be diagnosed easily with characteristic clinical features and imaging finding on head CT or magnetic resonance imaging (MRI). Other causes of visual loss that may require urgent attention must be ruled out however. Most patients with PRES recover completely within a period of days to weeks (usually within 2 weeks), but a small number have residual neurologic deficits resulting from secondary cerebral infarction or hemorrhage. MRI findings can be helpful in identifying patients with worse prognosis.