Atypical Presentation of Posterior Reversible Encephalopathy Syndrome (PRES): A Case Report and Review of the Literature.

Posterior reversible encephalopathy syndrome (PRES) is a reversible clinico-radiological entity characterized by acute neurological symptoms and white matter vasogenic edema that commonly affects the posterior occipital and parietal lobes of the brain. Patients with this condition usually present with complaints of headache, encephalopathy, seizures, or visual disturbances. Nystagmus and periodic alternating gaze are rarely reported presentations of PRES patients. Similarly, involvement of the brainstem, cerebellum, basal ganglia, and other cerebral areas are atypical findings on brain imaging. Early diagnosis and immediate treatment can reverse both the clinical and radiological features of PRES.