In a retrospective review, 3 (3.8%) of 78 patients developed recurrent posterior reversible encephalopathy syndrome. Underlying clinical conditions included sickle cell disease, antibody-positive autoimmune disease, and allogeneic bone marrow transplantation. Infection (bacterial/viral) was suspected or documented in both episodes in all 3 patients. Evidence of endothelial injury (schistocyte formation and increased lactate dehydrogenase) was documented in all patients, and multiple organ dysfunction syndrome developed during the hospital course of all admissions.