Central Variant Posterior Reversible Encephalopathy Syndrome, the Brainstem, and Chronic Kidney Disease: Call for Rapid Diagnosis With Brain Magnetic Resonance Imaging

Posterior reversible encephalopathy syndrome (PRES) is characterized by reversible vasogenic edema that most commonly involves the parieto-occipital regions. Isolated brainstem involvement, as is seen in the case of central variant PRES (cvPRES), is rare. PRES can be the first presentation of chronic kidney disease and hypertension; we report a combination of both, with brainstem involvement and atypical presentation (acute loss of consciousness versus typical confusion and seizures). Our patient, a man in his 30s with hypertension and stage IV chronic kidney disease, was found unresponsive with blood pressure 266/166 mmHg. Head computed tomography and angiography showed no evidence of hemorrhage or occlusion. He was admitted with acute-on-chronic kidney disease requiring emergent dialysis. Brain magnetic resonance imaging (MRI) with and without contrast showed pontine enlargement with diffuse T2 hyperintensity with no evidence of restricted diffusion. He was diagnosed with cvPRES. His blood pressure was aggressively controlled with continuous nicardipine infusion. Repeat MRI 8 days later showed partial resolution of T2 hyperintensities. MRI, particularly diffusion-weighted imaging, is the preferred diagnostic tool for PRES because it allows differentiation of vasogenic edema from cytotoxic edema, enabling timely diagnosis and treatment that can lead to complete remission. In patients with the appropriate clinical context, repeat MRI to assess interval improvement may help confirm cvPRES and avoid unnecessary invasive evaluation of brainstem abnormalities.