MRI-Negative Posterior Reversible Encephalopathy Syndrome: Comparison of Hypertensive Encephalopathy With and Without...

To explore whether posterior reversible encephalopathy syndrome (PRES) can present with negative magnetic resonance imaging (MRI) by comparing clinical features between cases of PRES with vasogenic edema and cases of hypertensive encephalopathy without MRI changes.

Patients diagnosed with hypertensive encephalopathy from August 1, 2008, to December 31, 2017, were identified retrospectively and matched by age (±5 years) and sex in a 1:2 ratio to patients retrospectively identified as having PRES from January 1, 2002, to November 30, 2017. A review of MRI images and clinical information was performed.

We identified 16 cases of hypertensive encephalopathy and 32 age- and sex-matched controls with PRES showing vasogenic edema on MRI. There were no statistically significant differences in the odds of presentation with headache (odds ratio [OR], 1.372; 95% CI, 0.458 to 4.106), encephalopathy (OR, 2.303; 95% CI, 0.433 to 12.236), visual disturbance (OR, 0.826; 95% CI, 0.185 to 3.697), or focal neurologic deficit (OR, 4.000; 95% CI, 0.767 to 20.872). Seizures were more common in patients with vasogenic edema (OR, 0.082; 95% CI, 0.010 to 0.664). There were no significant differences in odds of acute kidney injury (OR, 2.90; 95% CI, 0.679 to 12.449) or odds of having a history of malignancy (OR, 0.295; 95% CI, 0.076 to 1.152), transplantation (OR, 3.347; 95% CI, 0.594 to 18.880), or autoimmune disease (OR, 0.400; 95% CI, 0.104 to 1.532). Systolic blood pressure at presentation was higher in patients with hypertensive encephalopathy and negative MRI as compared with patients with PRES and vasogenic edema (OR, 1.03; 95% CI, 1.01 to 1.05).

Most presenting symptoms and risk factors were not significantly different between cases of hypertensive encephalopathy with and without vasogenic edema, arguing that the diagnosis of PRES in the setting of acute severe hypertension may not depend on MRI confirmation.