- kind of misnomer - affect RBC, PLATELETS, WBC - hemocytoblast gets converted into a myeloid stem cell and it gets converted into a lymphoid stem people with 65% of this anemia is idiopathic caused by drugs, chloramphenicol, or by benzenes, or streptomycin; destruction of the bone marrow; destroying the myloid stem cell which destroys the 3 lineages; • low blood cells • low white blood cells • low platelets (thrombocytopenia) Called: Pancytopenia