Abstract W P360: A Hypertensive Reversible Encephalomyelitis Syndrome (HyRES)

Abstract

Introduction: Six patients have been described in the published literature with a clinical and radiographic presentation consistent with posterior reversible encephalopathy syndrome (PRES), but who also had extensive spinal cord lesions on MRI. We add two additional cases and after analyzing all eight cases have discovered characteristic patterns. In light of the already wide definition of PRES, we propose a new syndrome named hypertensive reversible encephalomyelitis syndrome or HyRES. Methods: We searched the Medline database using the terms “spinal PRES” and “spinal hypertensive encephalopathy,” which led to the identification of four case reports, that referenced another two cases. We analyzed these six cases in addition to our two cases. Results: Average age was 31 with five male and three female. All patients had severe acute hypertension and a longitudinally extensive myelitis with a confluent, expansive central cord T2 hyperintensity greater than 4 spinal segments in length, always involving the cervical spine. (see Figure 1) Almost all patients had hypertensive retinopathy (7/8), a favorable clinical course with only antihypertensive treatment (7/8), and resolution of the spinal cord lesions on follow-up imaging (7/8). Half of the patients had symptoms referable to the spinal cord lesions. Many of the features that are commonly seen in classic PRES were not present, such as seizure (0/8). Conclusion: HyRES shares clinical, radiographic, and, presumably, pathophysiologic attributes with PRES, but is a unique and consistent entity. Clinicians should suspect HyRES when patients with PRES have neurologic signs referable to the spinal cord or MRI lesions that extend to the cervicomedullary junction. It is important that clinicians and radiologists identify HyRES when they are considering, working up, or treating other causes of longitudinally extensive myelitis, which can have significant morbidity.