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 Aplastic anemia can progress to all except - and explain in detail?
PNH is the only hemolytic anemia caused by an acquired intrinsic defect in the cell membrane. PNH arises in the setting of aplastic anemia and these patients are at increased risk of developing acute myelogenous leukemia.
Aplastic anemia may progress to PNH and MDS.