You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is What is the most common cause for Budd chiari syndrome : and explain in detail?
Answer is D (Polycythemia vera): Amongst the options provided Polycythemia vera is the commonest cause of Budd chiary syndrome. Budd chiari syndrome includes acute, subacute or chronic occlusion of hepatic vein most commonly caused by hepatic vein thrombosis. Hepatic vein thrombosis is associated with in decreasing order of frequency: - Polycythemia vera Q - Pregnancy - Postpaum state - Use of oral contraceptives - Paroxysmal nocturnal hemoglobinuria (PNH) Q - lntraabdominal cancers, paicularly hepatocellular carcinoma