We describe a case of bone marrow necrosis (BMN) with subsequent fat embolism precipitated by high altitudes in a young healthy man with previously undiagnosed sickle cell-beta thalassemia. This case report adds to the growing literature on the complexity of diagnosing bone marrow necrosis given that the clinical and laboratory features mimic thrombotic thrombocytopenic purpura. This BMN with fat embolism syndrome (FES) is novel in that it was precipitated by high altitudes and the patient was treated successfully with a series of therapeutic plasma exchanges and red blood cell transfusions alone, without any adverse long-term complications to the patient.