key: cord-0964420-svrwz34f authors: Lallana, Sofia; Siegler, James E. title: Response to correspondence concerning “Posterior reversible encephalopathy syndrome (PRES) associated with COVID-19” date: 2021-08-14 journal: J Clin Neurosci DOI: 10.1016/j.jocn.2021.08.006 sha: 711734906c6e611b90a24430b68de93fda9665fa doc_id: 964420 cord_uid: svrwz34f nan We thank Sun et al. 1 for their interest and comments on our article 2 , specifically with regard to case 1. In that case, we reported a previously healthy 49-year-old woman who developed sudden vision loss and right sided hemiparesis during the course of her infection with SARS-CoV-2, with computerized tomography (CT) angiography evidence of bilateral posterior cerebral artery stenosis. Given the initial suspicion of arterial ischemic stroke, intravenous thrombolysis was initiated, and after identifying luminal irregularities concerning for stenosis (and possible vasospasm) during conventional angiography, empirical therapy with intraarterial nimodipine was administered. Ten days after the onset of visual symptoms, magnetic resonance imaging (MRI) was performed, showing a significant improvement of the occipital lesions observed previously. MR angiography was simultaneously performed and no vasculopathy was observed. We agree with Sun et al. that in this case exhibits features that are consistent with reversible cerebral vasoconstriction syndrome (RCVS), and we ourselves had several doubts characterizing the disorder. Initially, the arteriographic findings in conjunction with the patient's sex and absence of vascular risk factors raised our pre-test probability of RCVS. It was because of this suspicion that we administered intraarterial nimodipine, and the patient demonstrated radiographic improvement of the vasculopathy. However, the absence of characteristic headache or RCVS trigger would be atypical for this condition. Moreover, PRES has a known association between immunomodulatory therapies, is increasingly recognized as a complication of severe SARS-CoV-2 infection, and demonstrates classic posterior predominant and oftentimes reversible vasogenic edema-as in our patient. With regard to the RCVS2 score 3 , it was designed to distinguish RCVS from primary angiitis of the central nervous system-not from posterior reversible encephalopathy. Therefore, we would not recommend it to be used to differentiate RCVS from other vasculopathies or parenchymal pathologies. Further, we would respectfully contend her RCVS2 score would be a 1 (for female sex), as there was no immediate vasoconstrictor trigger (3 points), subarachnoid hemorrhage (1 point) or antecedent headache (5 points). We think this case highlights an important relationship between PRES and RCVS 4 , and a shared pathophysiology between those two entities. In addition, several cases of PRES 5-9 and RCVS 10 have been described in context of SARS-COV-2 infection, which supports the theory of an endothelial disfunction and blood-brain barrier breakdown in these patients, which can lead to atypical radiological findings such as focal vasoconstriction, edema, and hemorrhage. Journal of Clinical Neuroscience Correspondence concerning " Posterior reversible encephalopathy syndrome ( PRES ) Posterior reversible encephalopathy syndrome (PRES) associated with COVID-19 RCVS2 score and diagnostic approach for reversible cerebral vasoconstriction syndrome Posterior Reversible Encephalopathy Syndrome and Reversible Cerebral Vasoconstriction Syndrome: Clinical and Radiological Considerations Rare presentations of COVID-19: PRES-like leukoencephalopathy and carotid thrombosis Posterior reversible encephalopathy syndrome (PRES): Another imaging manifestation of COVID-19. Interdiscip Neurosurg Adv Tech Case Manag Posterior reversible encephalopathy syndrome in patients with COVID-19 Transient cortical blindness in COVID-19 pneumonia; a PRES-like syndrome: Case report Reversible Encephalopathy Syndrome (PRES) in a COVID-19 patient Reversible cerebral vasoconstriction syndrome and dissection in the setting of COVID-19 infection Posterior reversible encephalopathy has a known overlap with reversible cerebral vasoconstriction syndrome (RCVS).COVID-19 may put critically ill patients at greater risk of posterior reversible encephalopathy syndrome.