Overlapping features of posterior reversible encephalopathy syndrome and reversible cerebral vasoconstriction...

Posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS) are cerebrovascular dysregulation syndromes, and an overlapping spectrum may exist. We aimed to assess the frequency and features of PRES and RCVS overlaps.

We retrospectively included patients diagnosed with PRES or RCVS from our tertiary center during 2008-2018. Subgroups of PRES with vasoconstriction and RCVS with resolving vasogenic brain edema were defined as the overlap group. Inter-group comparisons were performed for clinical, radiological, and laboratory features.

Of 360 patients (mean age 48 years, 73% female), 242 were diagnosed with PRES, 83 with RCVS, and 35 patients had overlapping features. In the overlap group, ischemic infarcts (31%) and intraparenchymal hemorrhage (34%) were more frequent than in isolated RCVS (15%, p = 0.03, and 11%, p < 0.01) or isolated PRES (12% and 13%, p-values <0.01). Subarachnoid hemorrhage was more common in overlap (17%) than in isolated PRES (5%, p = 0.006), but similar to isolated RCVS (25%, p = 0.337). Distal vascular segments were most involved (>50%) by vasoconstriction in RCVS and overlap cases. Neutrophil-to-lymphocyte ratio was higher in overlap (7.4) than in RCVS (2.7, p = 0.02), but similar to PRES (7.4). Most patients had a favorable discharge disposition (home or acute rehabilitation). There was one death (1%) with RCVS, one with overlap (3%), and 17 (7%) with PRES.

Although more distinct clinical and radiological features exist in typical RCVS and PRES, an overlapping presentation is not uncommon. Overlap may be associated with more ischemic and hemorrhagic complications, but mostly resembles the parent condition.