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 30 year old male patient presents with the following symptoms, breathlessness, irritability and confusion. He gives a history of fracture of his right arm 3 days ago. On physical examination, a diffuse petechial rash is seen. Blood examination reveals thrombocytopenia. The most likely diagnosis for this patient will be? \nSelect and explain. \nA. Fat embolism syndrome, B. Dengue, C. Caisson disease, D. Trosseau syndrome', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Symptomatic fat embolism syndrome\xa0is characterized by pulmonary\xa0insufficiency,\xa0neurologic\xa0symptoms,\xa0anemia, thrombocytopenia, and a diffuse petechial rash that is fatal in 10% of cases.\xa0\nClinical signs and symptoms appear 1 to 3\xa0days\xa0after\xa0injury\xa0as\xa0the\xa0sudden\xa0onset\xa0of\xa0tachypnea, dyspnea, tachycardia, irritability, and restlessness, which can progress rapidly to delirium or coma. Thrombocytopenia\xa0is\xa0attributed\xa0to\xa0platelet\xa0adhesion\xa0to\xa0fat\xa0globules\xa0and subsequent\xa0aggregation\xa0or\xa0splenic\xa0sequestration;\xa0anemia can result from similar red cell aggregation and/or hemolysis. A diffuse petechial rash (seen in 20%–50% of cases) is related to rapid onset of thrombocytopenia and can be a useful diagnostic feature.\nThe pathogenesis of fat emboli syndrome involves both mechanical obstruction and biochemical injury. Fat microemboli occlude pulmonary and cerebral microvasculature, both directly and by triggering platelet aggregation. This deleterious effect is exacerbated by fatty acid release from lipid globules, which causes local toxic endothelial injury. Platelet activation and granulocyte recruitment (with free radical, protease, and eicosanoid release) complete the vascular assault.\nRobin’s Textbook of pathology 10th ed Page 112', 'role': 'assistant'}]