Review Question - QID 214740

This patient is presenting with hypertension, encephalopathy, visual changes, seizures, and an MRI demonstrating edema primarily in the occipital lobes with some temporal lobe involvement. These symptoms are concerning for posterior reversible encephalopathy (PRES) syndrome.

PRES syndrome is a clinical radiographic diagnosis describing vasogenic edema in the occipital lobe secondary to hypertension, impaired cerebral blood flow regulation, and endothelial dysfunction. It is associated with preeclampsia, eclampsia, and immunosuppression. The classic presenting symptoms are confusion, visual changes ranging from blurry vision to cortical blindness, hypertension, and seizures. MRI is critical in the diagnosis and will demonstrate cerebral edema (hyperintensity on T2-weighted-Fluid-Attenuated Inversion Recovery [T2-FLAIR]) most commonly in the occipital and parietal lobes. The treatment involves treating any underlying conditions, gradually lowering the patient's blood pressure, and administering antiepileptic medications, if necessary.

Triplett et al. studied the diagnosis and management of posterior reversible encephalopathy syndrome (PRES). The authors found that PRES is associated with a wide variety of conditions including eclampsia and pre-eclampsia, hypertension, malignancy, sepsis, and others. They found that encephalopathy ranging from mild confusion to coma is a common presenting symptom. The authors recommend that neuroimaging is crucial for the diagnosis of PRES and further research is needed to determine the etiology.

Figure/Illustration A is a T2 FLAIR MRI of the brain demonstrating edema (hyperintensity) in the occipital lobe (red arrows) with additional hyperintensity in the temporal lobes. This is characteristic of PRES syndrome.

Incorrect Answers:
Answer 1: Eclampsia is possible in this postpartum patient and would present with hypertension, proteinuria, and seizures. This patient's MRI is suggestive of PRES syndrome. Though eclampsia is a possible etiology of PRES syndrome, it is not defined by the vascular edema seen in the imaging findings. Instead, these are pathognomonic for PRES.

Answer 2: Multiple sclerosis is a possible cause of seizures and autonomic dysfunction. Patients typically present with relapsing, remitting neurological symptoms over an extended period of time. On T2-weighted MRI, imaging findings for MS include periventricular and juxtacortical white matter lesions disseminated throughout multiple brain regions, rather than the contiguous, diffuse signal change caused by the edema associated with PRES. MS is an unlikely diagnosis in this hypertensive patient with a severe and acute presentation.

Answer 4: Severe preeclampsia would present with hypertension (systolic blood pressure > 160 mmHg) and proteinuria as well as other signs of end-organ dysfunction. The presence of seizures defines the progression of preeclampsia to eclampsia.

Answer 5: Subarachnoid hemorrhage would present with a sudden onset, severe headache, meningeal signs, and radiographic evidence of blood in the subarachnoid space. Seizures are a possible but less common initial presenting symptom.

Bullet Summary:
Posterior reversible encephalopathy (PRES) syndrome presents with seizures, headache, hypertension, and visual disturbances with edema in the occipital lobes seen in MRI and is associated with hypertension and altered cerebral blood flow regulation.