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': 'Which is not a feature of paroxysmal nocturnal hemoglobinuria - \nSelect and explain. \nA. Increased LAP score, B. Thrombosis, C. Thrombocytopenia, D. Hemolysis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Clinical features of PNH\nA. Intravascular hemolysis\n\nThe main feature of PNI-I is increased intravascular hemolysis that results in\n\n\n\nHemoglobinemia \xa0 \xa0 \xa0 \xa0 \xa0\xa0\n\n\nHemoglobinuria\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\xa0\n\n\nHemosiderinuria\n\n\nIncreased urine urobilinogen\xa0\xa0\n\n\nDecreased serum haptoglobin\xa0\n\n\nIncreased serum LDH\xa0 \xa0 \xa0 \xa0 \xa0\xa0\n\n\nIncreased serum bilirubin\n\n\n\nThe hemolysis is paroxysmal and usually occurs in the night because during sleep the pH of blood gets slightly reduced and acidic medium leads to activation of the complement.\n\nB. Thrombosis\n\nIn PNH there is episodic thrombosis due to the absence of CD-59 on platelets, this results in the externalization of phosphatidylserine, a site for prothrombinase complexes and thus increase the propensity for thrombosis.\nIntrabdominal veins are the most common sites of thrombosis that may result in Budd Chiari syndrome due to hepatic vein thrombosis.\n\nC. Other features\n\nThrombocytopenia\nGranulocytopenia\nDecreased LAP score\nNormoblastic hyperplasia of bone marrow\nPNH patients are also at increased risk for developing acute myelogenous leukemia and aplastic anemia.', 'role': 'assistant'}]