Successful treatment with eculizumab for posterior reversible encephalopathy syndrome due to underlying transplant‐associated thrombotic microangiopathy in patients transplanted for sickle cell disease

: Preexisting endothelial dysfunction and vascular injury sustained during allogeneic hematopoietic cell transplantation (HCT) increases risk for endothelial injury-related complications such as posterior reversible encephalopathy syndrome (PRES) and transplant-associated thrombotic microangiopathy (TA-TMA) in patients with sickle cell disease (SCD). We report two patients with SCD who developed PRES following allogeneic HCT. In both patients, PRES-related symptoms resolved only after a diagnosis of TA-TMA was established and eculizumab therapy was initiated. Renal manifestations at diagnosis included non-nephrotic range proteinuria and hypertension. This report highlights the importance of screening PRES-affected SCD HCT recipients for TA-TMA as usual treatment strategies may be inadequate.