Myelodysplastic syndromes (MDS)
It is a heterogeneous group of diseases with very similar features, and sometimes difficult to differentiate from one another. In all of them, the bone marrow starts to fail in producing enough blood cells. Not only white blood cells are affected. Myelodysplastic syndromes can affect platelets or red blood cells, too, and feature at least one type of cytopenia. Moreover, in myelodysplastic syndromes, the cells found in the bone marrow and the blood do not look normal under the microscope, which gives the disease its name.
Myelodysplastic syndromes are thought to be preleukemic because many patients develop acute leukemia at some point in the disease. There’s much more to learn about this umbrella term in our article about myelodysplastic syndromes.