Pediatric transfusion-associated posterior reversible encephalopathy syndrome

Abstract

Posterior reversible encephalopathy syndrome (PRES) is a clinicoradiological syndrome characterized by headache, altered mental state, seizures, and visual loss. It has a diverse etiology, of which hypertension is the most common. However, transfusion-associated PRES is being increasingly recognized, although pediatric reports are rare. We hereby report a 7-year-old boy with β thalassemia major, who developed neurological symptoms with changes suggestive of PRES on imaging after routine transfusions with an elevation of hemoglobin levels >5 g/dl posttransfusion. He required mechanical ventilation with standard therapies for raised intracranial pressure. The cerebral edema was characterized as vasogenic, due to the absence of diffusion restriction on magnetic resonance imaging of the brain and the child made a complete neurological recovery with normalization of imaging findings 4 weeks later. Interestingly, in concordance with the pressure, autoregulation disruption theory as a mechanism of hypertensive PRES, literature review on viscosity based autoregulation disruption shows that this may be one of the mechanisms among others for PRES associated with blood transfusion.

Keywords

• posterior reversible encephalopathy syndrome
• transfusion
• viscosity autoregulation