Leukopenia (also known as leukocytopenia, or leucopenia, from Greek λευκό-white and πενία-deficiency)'s a decrease in the number of white blood cells (leukocytes) found in the blood, which places individuals at increased risk of infection. Neutropenia's a sub-type of leukopenia that refers to a decrease in the number of circulating neutrophil granulocytes, the most abundant white blood cells. The terms leukopenia and neutropenia may occasionally… (More on Leukopenia)