This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
[{'content': 'A 67 year old woman with a prosthetic aortic valve develops progressive anemia. Examination of a peripheral blood smear reveales reticulocytsis and schistocytes. What is the appropriate diagnosis \nSelect and explain. \nA. Aconthocytosis, B. Henoch - schonlein purpura, C. Idiopathic thrombocytopemic purpura, D. Macroangiopathic hemolytic anemia', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Macroangiopathic heamolytic anemia most commonly results from direat erythrocyte trauma due to an abnormal vascular surface (eg: prosthetic heart valve, synthetic vascular graft). Anemia is mild to moderate and is accompained by an appropriate reticalocyte response.\nBlood smear examination reveals Fragmented red blood cells (Schistocytes) and polychromasia. Although microangiopathic heamolytic anemia results in morphologically similar red blood cells, it reflects changes in small.\nDiagnosis: Macroangiopocthia heamolytic anemia.', 'role': 'assistant'}]