What is the difference in the sub types of aml leukemia my daughter had m4 and passed away from it she had a very high WBC before a starting chemo?

Subtypes of AML. The various subtypes of AML are based on what type of cell has turned leukemic and how mature (or differentiated) the cell is. AML m4 can be dangerous because it likes to get into the brain and can cause very high counts. The leukemia and lymphoma society of america has very good information on its website that you may find useful. I am very sorry for your terrible loss.