Large Granular Lymphocyte (LGL) leukemia is a clonal disorder involving tissue invasion of marrow, spleen and liver. Clinical presentation is dominated by recurrent infections associated with neutropenia, anemia, splenomegaly, and auto-immune diseases, particularly rheumatoid arthritis. Both T cell and NK cell subtypes of LGL leukemia are indolent disease and considered as a chronic illness and lead to a treatment in more than 60% of patients.