Acute leukemia, infiltrative malignancy (e.g. lymphoma, multiple myeloma, metastatic carcinoma)<unk> , myelofibrosis
Aplastic anemia
Paroxysmal nocturnal hemoglobinuria
Medication/radiation induced
Tuberculosis, AIDS
Leishmaniasis, brucellosis, histoplasmosis.
Viruses causing aplastic anemia (hepatitis, Epstein-Barr virus, HIV, parvovirus B19)
Systemic lupus erythematosus
Hypersplenism
Myelodysplastic syndrome
Acute leukemia, infiltrative malignancy 
Acute myeloid leukemia
Myelodysplastic syndrome, myelofibrosis
Leukemoid Reaction
Aplastic anemia
Chronic myeloid leukemia
Paroxysmal nocturnal hemoglobinuria