{Reference Type}: Case Reports {Title}: Fat Embolism Syndrome Mimicking Thrombotic Thrombocytopenic Purpura in a Patient With Hemoglobin S/Beta-Thalassemia. {Author}: Se B;Frisch A;Hwang MW;Polani F;Bade N; {Journal}: J Hematol {Volume}: 13 {Issue}: 3 {Year}: 2024 Jun 暂无{DOI}: 10.14740/jh1274 {Abstract}: Thrombotic microangiopathies cause ischemic organ damage and require urgent management for a favorable prognosis. Fat embolism syndrome from bone marrow necrosis is a rare and unique pathology that carries a high mortality rate. It can mimic thrombotic microangiopathies such as thrombotic thrombocytopenic purpura (TTP). Herein, we present a patient with sickle cell-beta-thalassemia who initially presented with a vaso-occlusive crisis, lab evidence of hemolysis, schistocytes and thrombocytopenia who developed acute encephalopathy with respiratory distress, consistent with TTP. She was found to have multiple infarcts in the brain. She was intubated and underwent plasma and red cell exchange. Bone marrow biopsy confirmed marrow necrosis from her vaso-occlusive crisis and subsequently, fat embolism syndrome. Here, we discuss the complex presentation and the complications of fat embolism from bone marrow necrosis and how it can mimic TTP.