Posterior Reversible Encephalopathy Syndrome in End-Stage Kidney Disease: Not Strictly Posterior or Reversible

Posterior reversible encephalopathy syndrome (PRES) is an uncommon clinico-radiological condition that can result in severe brain injury. The pathogenesis of cerebral vasogenic edema, the hallmark of PRES, is not fully understood. Despite its name, there is substantial heterogeneity both in terms of imaging findings and outcome. Relatively little is known about PRES in kidney disease despite the clustering of risk factors including hypertension, autoimmune disease and immunosuppression. In a retrospective observational study of incident end-stage kidney disease patients in Southwest Ireland over a ten year period, we discovered five cases of PRES representing an incidence of 0.84% in this patient population. These five cases highlight the variability in clinical presentation and the potentially life-threatening nature of this condition. We provide an in-depth review of the existing literature regarding PRES in terms of its pathogenesis and heterogeneity, as well as the experience of PRES in ESKD patients. PRES appears to be rare in the ESKD population but could be under-recognized. Marked hypertension is a cardinal risk factor in this population, associated with extracellular fluid volume expansion. Neuroimaging findings can be diverse involving both anterior and posterior circulation territories. Three of the five patients described had commenced haemodialysis within four weeks of their presentation. These patients may be particularly vulnerable to microvascular brain injury, which can be devastating. This emphasises the need for clinicians to pay meticulous attention to extracellular fluid volume control during this potentially hazardous period.