Posterior Reversible Encephalopathy Syndrome after Hematopoietic Cell Transplantation in Children with Hemoglobinopathies.

Posterior reversible encephalopathy syndrome (PRES) is a serious adverse event associated with calcineurin inhibitors used for graft-versus-host disease (GVHD) prophylaxis. We compared the incidence of PRES in children with thalassemia (n = 222, 1.4 to 17.8 years old) versus sickle cell disease (SCD; n = 59, 2 to 17 years old) who underwent hematopoietic cell transplantation from HLA-matched siblings or alternative donors and analyzed the risk factors for PRES. Overall, 31 children developed calcineurin inhibitor-related PRES (11%), including 30 patients with seizures and 1 patient without seizures. PRES incidence was significantly higher in SCD patients (22%; 95% confidence interval [CI], 10% to 32%) than in thalassemia patients (8%; 95% CI, 5% to 12%;P = .002). In multivariate analysis, factors associated with PRES were hypertension (hazard ratio [HR], 5.87; 95% CI, 2.57 to 13.43; P = .0001), SCD (HR, 2.49; 95% CI, 1.25 to 4.99; P = .009), and acute GVHD (HR 2.27; 95% CI, 1.06 to 4.85; P= .031). In the entire cohort overall survival (OS) was significantly higher in patients without versus with PRES (90% versus 77%; P = .02). In a subgroup analysis that including matched sibling transplants, OS and disease-free survival (DFS) were similar in thalassemia patients without PRES (92% and 88%, respectively) and with PRES (82% and 73%, respectively), whereas SCD patients with PRES had significantly lower OS (67%) and DFS (67%) than patients without PRES (94% and 94%, respectively; P = .008). Thus, SCD patients had a significantly higher incidence of PRES than thalassemia patients, and hypertension and GVHD were the 2 main risk factors for PRES in patients with hemoglobinopathies. Although PRES did not significantly influence survival in patients with thalassemia, patients with SCD had significantly lower survival after PRES.